Дисертації: "Mechatronics engineering in defence systems"

1

Dawson, Richard Jonathan. "Performance-based management of flood defence systems." Thesis, University of Bristol, 2003. http://hdl.handle.net/1983/25b216eb-2068-47f2-b689-f3e0091f85fb.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

2

Kanjanapas, Kan. "Human Mechatronics Considerations of Sensing and Actuation Systems for Rehabilitation Application." Thesis, University of California, Berkeley, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3640496.

Повний текст джерела

Анотація:

With the predicted increase in worldwide elderly population in the future and already significant populations of disabled people, assistive technologies and rehabilitation devices are demanded significantly. Utilizing a human mechatronic approach results in several advantages, including capability of measuring insightful information for patient's condition and providing proper assistive torque for abnormal movement correction. This dissertation investigates several domains, including (1) human dynamics model, (2) monitoring systems, and (3) design and control of active lower extremity exoskeleton.

The dissertation begins with a study of a human dynamic model and sensing system for diagnosis and evaluation of patient's gait condition as first step of rehabilitation. A 7-DOF exoskeleton equipped with multiple position sensors and smart shoes is developed, so that this system can deliver patient's joint motion and estimated joint torque information. A human walking dynamic model is derived as it consists of multiple sub-dynamic models corresponding to each gait phase. In addition, a 3D human motion capture system is proposed as it utilizes an inertial measurement unit (IMU) sensor for 3D attitude estimation with embedded time varying complementary filter. This sensing system can deliver 3D orientations of upper extremities, and a forward kinematics animation. For the development of a rehabilitation device, an active lower extremity exoskeleton is proposed. A rotary series elastic actuator (RSEA) is utilized as a main actuator of the exoskeleton. The RSEA uses a torsion spring yielding elastic joint characteristics, which is safe for human robot interaction applications. A RSEA controller design is implemented, including a PID controller, a feedforward controller for friction compensation, and a disturbance observer for disturbance rejection. All sensing and actuation systems developed in this dissertation are verified by simulation studies and experiments.

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Sherman, Matthew. "A Hands-on Method of Instruction for Feedback Control Systems and Mechatronics." Honors in the Major Thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/805.

Повний текст джерела

Анотація:

This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf
Bachelors
Engineering and Computer Science
Mechanical Engineering

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Erdener, Onur Alper. "Development Of A Mechatronics Education Desk." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1095066/index.pdf.

Повний текст джерела

Анотація:

In this thesis a mechatronics education desk is developed. The system developed is a low cost, versatile mechatronics education and teaching environment that aims to facilitate hands-on education of undergradutate level mechatronics students. The desk is formed of three main modules that address the needs of mechatronics education: The WorkDesk, Mechatronic Building Blocks and Experimental Setups. These parts are well designed and presented to form a complete and coordinated solution for mechatronics education. The WorkDesk is a platform devoted to the mechatronics engineering trainee, which provides mechanical, electrical and software prototyping that enables studying, testing and parts integration for mechatronic projects. The components building up the WorkDesk are selected or developed to facilitate mechatronics design and prototyping. Mechatronic building blocks necessary for mechatronics teaching are identified and selected to be a part of the system. In order to support these modules, low cost custom building blocks are also developed. These include, an autonomous mobile robot kit and a versatile interface board called ready2go. Demonstrative experiments with custom developed building blocks are also presented. Two experimental setups are developed and presented in the scope of the thesis. The setups, Intelligent Money Selector and Heater/Cooler, address and demonstrate many aspects of mechatronic systems as well as aid introducing systems approach in mechatronics education. As a consequence, a mechatronics education desk is developed and presented with many hands-on educational case studies. The system developed forms an extensible and flexible software and hardware architecture and platform that enables integration of additional mechatronics education modules.

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Proesser, Malte. "A new approach to systems integration in the mechatronic engineering design process of manufacturing systems." Thesis, De Montfort University, 2014. http://hdl.handle.net/2086/10492.

Повний текст джерела

Анотація:

Creating flexible and automated production facilities is a complex process that requires high levels of cooperation involving all mechatronics disciplines, where software tools being utilised have to work as closely as their users. Some of these tools are well-integrated but others can hardly exchange any data. This research aims to integrate the software systems applied by the mechatronic engineering disciplines to enable an enhanced design process characterised by a more parallel and iterative work flow. This thesis approaches systems integration from a data modelling point of view because it sees information transfer between heterogeneous data models as a key element of systems integration. A new approach has been developed which is called middle-in data modelling strategy since it is a combination of currently applied top-down and bottom-up approaches. It includes the separation of data into core design data which is modelled top-down and detailed design data modules which are modelled bottom-up. The effectiveness of the integration approach has been demonstrated in a case study undertaken for the mechatronic engineering design process of body shop production lines in the automotive industry. However, the application of the middle-in data modelling strategy is not limited to this use case: it can be used to enhance a variety of system integration tasks. The middle-in data modelling strategy is tested and evaluated in comparison with present top-down and bottom-up data modelling strategies on the basis of three test cases. These test cases simulated how the systems integration solutions based on the different data modelling strategies react to certain disturbances in the data exchange process as they would likely occur during industrial engineering design work. The result is that the top-down data modelling strategy is best in maintaining data integrity and consistency while the bottom-up strategy is most flexibly adaptable to further developments of systems integration solutions. The middle-in strategy combines the advantages of top-down and bottom-up approaches while their weaknesses and disadvantages are kept at a minimum. Hence, it enables the maintenance of data modelling consistency while being responsive to multidisciplinary requirements and adaptive during its step-by-step introduction into an industrial engineering process.

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Roos, Fredrik. "On design methods for mechatronics : servo motor and gearhead." Licentiate thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-167.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Lasa, Morán J. Mikel. "A systems engineering approach for computer based design in mechatronics : a common rail application /." Düssdeldorf : VDI-Verl, 2002. http://www.gbv.de/dms/bs/toc/353099538.pdf.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Roos, Fredrik. "Towards a methodology for integrated design of mechatronic servo systems." Doctoral thesis, Stockholm : Maskinkonstruktion, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4473.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Lomaeus, Anton. "The Military Utility of Unmanned Aerial Systems for Swedish Tactical Deliveries : A Defence Systems Perspective." Thesis, Försvarshögskolan, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-10246.

Повний текст джерела

Анотація:

There is a rapid development within the unmanned aerial systems (UAS) technologies and the logistics industry leads the research, motivated by potential future profits when used for last-mile deliveries. The military have used unmanned aerial vehicles (UAV) for many decades, but the military usage of UAVs for deliveries is almost unheard of. The main purpose of the study is to theoretically evaluate if existing payload carrying UAVs could increase the Swedish defence-logistics organizations capabilities. This study is delimited to tactical deliveries and UAVs with a maximal takeoff weight of less than 250 kg. This study begins by investigating the Swedish Armed Forces logistical needs and the capabilities of the existing UAVs. It then performs a research overview in the subject to be updated on the latest insights which are complemented by discussions with expertise in the subject. The theory utilized are Systems Science, Systems Engineering and Military Capability which lay ground to the Military Utility concept which is developed to evaluate the value of military systems to support decision-makers when acquiring new complex systems. To evaluate the military logistics performance, Mosh Kress book Operational logistics was used. The research is split into three phases, phase one utilizes the insights from the background research to select UAVs to evaluate and to develop three potential scenarios. In phase two the Military Utility evaluation models are developed for each scenario. Phase three evaluates the concept systems performance for the scenarios. The conclusion is that there is circumstantial Military Utility with UAS within the Swedish logistics organization. The potential exists when used for their strengths such as low response time in hard-to-reach areas, and where there is a desire to remove the operators from danger during the transport. Further there is a potential to save operative costs in terms of man-hours, but UAVs are quite vulnerable to electronic disturbances and the cold and windy Swedish climate. The civil airspace regulation is also a major hinder for UAS effective use as well as their limited payload capacity.
Den teknologiska utvecklingen inom obemannade flygande system (UAS) går snabbt framåt. Det är logistikindustrin som leder forskningen motiverade av framtida vinster när tekniken används för sista kilometern-transporter. Militären har använt obemannade flygande fordon (UAV) i flera decennier, men inte för materielleveranser i någon betydande utsträckning. Det huvudsakliga syftet med den här studien är att teoretiskt utvärdera om befintliga transport UAV:er kan öka den svenska försvarslogistiska förmågan. Studien är avgränsad till taktiska leveranser med UAV:er som har en maximal startvikt på 250 kg. Studien börjar med att undersöka de svenska försvarslogistiska behoven samt förmågorna av existerande UAV:er. Den genomför sedan en forskningsöversikt i ämnet för att uppdateras om de senaste insikterna som även kompletteras av diskussioner med experter i ämnet. Teorin som används är Systemteori, Systemteknik och Militär förmåga som lägger grunden för det Militär Nytta-konceptet. Konceptet är utvecklat för att utvärdera värdet av militära system och förse beslutstagare med stöd vid anskaffande av nya komplexa system. För att utvärdera den militära logistikprestandan används Mosh Kress bok Operational Logistics. Genomförandet delas upp i tre faser. I fas ett används insikterna från initiala undersökningen för att välja ut UAV:er att utvärdera samt utvecklas tre potentiella scenarier. I fas två utvecklas Militära Nytta utvärderingsmodellerna för vartdera scenario. I fas tre utvärderas systemkonceptens prestanda i scenarierna. Slutsatsen är att Militär Nytta med UAS finns till varierande grad beroende på omständigheterna. Potentialen för tekniken finns främst när den används för sina styrkor till exempel vid behov av snabba leveranser till svåråtkomliga platser, samt när det finns ett behov att få bort förare från farliga platser. Vidare så finns det potential att spara operativa kostnader genom reducering av man-timmar, men UAV:er är ganska sårbara till elektroniska störningar och det svenska klimatet. Även luftrumsregelverken är ett hinder för effektiv användning samt dess begränsade lastkapacitet.

Стилі APA, Harvard, Vancouver, ISO та ін.

10

Gustafsson, Filip. "Waste heat recovery systems : Fuel energy utilisation for a marine defence platform." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-19681.

Повний текст джерела

Анотація:

This report is a thesis for BTH in collaboration with the company Saab Kockums AB. In order to meet future environmental and economical demands, a vessel must reduce its fuel consumption to have a smaller climate impact and save money. Waste heat recovery systems (WHRS) captures the thermal energy generated from a process that is not used but dumped into the environment and transfers it back to the system. Thermal energy storage (TES) is the method of storing thermal energy which allows heat to be used whenever necessary. Some applications of TES are seasonal storage, where summer heat is stored for use in the winter or when ice is produced during off-peak periods and used for cooling later. The purpose of this study is to investigate the possibilities of utilising a vessel’s waste heat by converting thermal energy into electrical energy. This thesis also aims to investigate conditions for SaltX Technology’s nano-coated salt as a potential solution for thermal energy storage. Initially, the expectations and requirements a future WHRS were investigated in a function analysis. Continuously, the method consisted of a combination of a literature review and dialogue with stakeholders. The literature review was used as a tool to identify, select and study concepts of interest built on scientifically proven facts. Dialogues with stake holders were held as a complement to the literature study to find information. The study showed that an organic Rankine cycle has the highest efficiency for low-medium temperature heat and is therefore most suitable to recover thermal energy from the cooling water. The concept of a steam Rankine cycle is most suitable for recovering thermal energy from the exhaust gases for direct use.The study obtained conditions and important properties for storing thermal energy in salt for later use. Finally, the result showed that a Stirling engine is the most efficient concept for conversion of stored energy into electrical energy. The conclusions are that there are great possibilities for waste heat recovery on marine defence platforms. A Stirling engine for energy conversion in combinations with thermal energy storage shows most promise as a future waste heat recovery system on this type of marine platform.
Denna rapport är ett examensarbete för BTH i samarbete med företaget Saab Kockums AB. Arbetet utforskar möjligheterna att möta framtida miljömässiga och ekonomiska krav genom att låta fartyg minska sin bränsleförbrukning. System för återvinning av spillvärme (WHRS) fångar upp värmeenergi som vanligtvis kyls ner eller släpps ut i naturen och för den tillbaka till systemet. Termisk energilagring (TES) är metoder för lagring av värme som gör det möjligt att använda termisk energi när det behövs. Vissa applikationer av TES är säsongslagring, där sommarvärme lagras för användning på vintern eller när is produceras under vintern och används för kylning senare. Syftet med denna studie är att undersöka möjligheterna att utnyttja ett fartygs spillvärme genom att omvandla termisk energi till elektrisk energi. Detta examensarbete syftar också till att undersöka förhållandena för hur SaltX Technology’s nanobelagda salt kan användas som en potentiell lösning för lagring av termisk energi. Inledningsvis undersöktes WHRS:s förväntningar och krav i en funktionsanalys. Fortsättningsvis bestod metoden av en kombination av en litteraturstudie och dialoger med intressenter. Litteraturstudien användes som ett verktyg för att identifiera, välja och studera intressanta koncept baserade på vetenskapligt beprövade fakta. Dialoger hölls som ett komplement till litteraturstudien för att hitta information. Studien visade att en organisk Rankine-cykel har den högsta verkningsgraden för låg-medelhög temperatur och därför är bäst lämpad för att återvinna energi buren i kylvattnet samt att en ång-Rankine-cykel är bäst lämpad för att utnyttja energin från avgaserna för direkt användning. Studien erhöll förhållanden för termisk energilagring i salt samt viktiga parametrar för systemet. Slutligen visade resultatet att en Stirlingmotor är det mest effektiva konceptet för omvandling av lagrad energi till elektrisk energi. Slutsatserna är att det finns stora möjligheter för återvinning av restvärme på marina försvarsplattformar. En Stirlingmotor för energiomvandling i kombination med termisk energilagring visar störst potential som ett framtida system för återvinning av spillvärme på denna typen av plattformar.

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Chen, Kenway. "MCAD - ECAD integration : constraint modeling and propagation /." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26484.

Повний текст джерела

Анотація:

Thesis (M. S.)--Mechanical Engineering, Georgia Institute of Technology, 2009.
Committee Chair: Schaefer, Dirk; Committee Member: Panchal, Jitesh; Committee Member: Paredis, Chris; Committee Member: Rosen, David; Committee Member: Yoder, Douglas. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Стилі APA, Harvard, Vancouver, ISO та ін.

12

Mölleryd, Bengt A. "An anatomy of technological innovation in infrastructure and defence systems in Sweden after the Cold War." Licentiate thesis, KTH, Kraft- och värmeteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-31494.

Повний текст джерела

Анотація:

The dual interaction of science and technology with defence, security and infrastructures for service provision as energy is a major theme in modern times. The era after the Second World War and in the course of the Cold War was accompanied and spurred by an amazing number of great technological advances and changes. The study investigates and discusses dimensions of the interaction between technology changes and innovation and defence, security and infrastructure systems in a small country as Sweden after the Cold War. The main result of the study is a proposal for an anatomy of technology innovation which can be seen as a predecessor to a system (or enterprise) architecture for technology innovation in defence, security and infrastructure systems. The approach is developed from previous international research and theories of innovation systems. Infrastructure and defence systems are investigated on three levels, technologies, system integration and services provided. Establishing an anatomy is supported by case studies which apply a stake holder perspective on development and innovation in systems. Prominent elements of the proposed anatomy for technology innovation are framework conditions or context, economic organizational factors such as people, knowledge, business models and finance, and last but not least culture for development and innovation, and the customer and user in the processes. Contexts and environmental conditions in recent times are characterised by more complicated threats and disturbances which potentially imply larger disruptions. The study explores how contexts and emerging conditions translate into plausible scenarios and their effect on the anatomy and the various stages of the innovation processes. The vital role in the anatomical framework played by culture for innovation is illuminated in the case studies. Other basic elements of the anatomy are the people, inventors and developers as the knowledge underpinning. Risk taking and sharing and the rights and responsibilities of the stake holders play substantial roles in the anatomy as some main economic organizational factors and elements of innovation.
QC 20110317

Стилі APA, Harvard, Vancouver, ISO та ін.

13

Sjöstedt, Carl-Johan. "Modeling and Simulation of Physical Systems in a Mechatronic Context." Doctoral thesis, KTH, Maskinkonstruktion (Avd.), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10522.

Повний текст джерела

Анотація:

This thesis gives different views on the modeling and simulation of physical systems, especially together with embedded systems, forming mechatronic systems. The main considered application domain is automotive. One motivation behind the work is to find suitable representations of physical systems to be used in an architectural description language for automotive embedded systems, EAST-ADL2, which is implemented as a UML2 profile, and uses concepts from both UML and SysML. As a part of the thesis, several languages and tools are investigated, including bond graphs, MATLAB/Simulink, Ptolemy II, Modelica, MATLAB/Simscape and SysML. For SysML, the modeling of continuous-time systems and how it relates to MATLAB/Simulink and Modelica is evaluated. A case study of an electric power assisted steering is modeled to show the differences, the similarities and the usage of the above mentioned languages and tools. To be able to classify the tools and languages, five realization levels were developed: Physical modeling models Constraint models Continuous causal models Discretized models Discretized models with solver and platform implementation By using these realization levels, models, tools and modeling languages can be classified, and transformations between them can be set up and analyzed. As a result, a method to describe the simulation behavior of a MATLAB/Simulink model has been developed using SysML activity diagrams as an approach to achieve integrated system models. Another result is an evaluation of the parametric diagrams of SysML for continuous-time modeling, which shows that they do not enable “physical modeling”, i.e. modeling the topology of the system and getting the underlying equations out of this topology. By including physical ports and physical connectors to SysML internal block diagrams, this could be solved. The comparison also shows many similarities between the languages. The results led to a more detailed investigation on conjugate variables, such as force and velocity, and electric current and voltage, and how these are treated in various languages. The thesis also includes two industrial case studies: one of a twin-screw compressor, and one of a simulation environment for automotive fuel-cell systems. Conclusions are drawn from these models, referring to the realization levels.
QC 20100810

Стилі APA, Harvard, Vancouver, ISO та ін.

14

Kandel, Robert. "Försvarsanskaffning : för att stödja befolkning eller industri?" Thesis, Försvarshögskolan, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-8524.

Повний текст джерела

Анотація:

Försvarsanskaffning och dess omkringliggande faktorer är relativt lite utforskat, särskilt i svensk kontext. En anledning är möjligtvis att utvecklingen skett fort och medfört att teorin har blivit ifrånsprungen. Det medför intresset av att studera faktorer som påverkar den svenska försvarsanskaffningen gällande valet av vem anskaffningen sker ifrån. Arbetet är en kvalitativ utforskande studie med en induktiv ansats med syfte att förstå de underliggande teman och mönster som finns bakom den svenska anskaffningsprocessen. Arbetet belyser anskaffningsprocessen relativt brett, därför används Hartleys teori byggd utifrån studier kring Ministry of defence i Storbritannien. Empirin utgörs av djupintervjuer där respondenterna representerar Försvarsmakten, FMV och politiken. Teorin används sedan för att analysera empirin, för att slutligen belysa inomvetenskapliga såväl som utomvetenskapliga utvecklingspunkter. Studien kom fram till att säkerhetspolitik och ekonomi påverkar den svenska anskaffningsprocessen av komplex försvarsmateriel i stor utsträckning. Påverkan är positiv exempelvis genom att den har spin-off effekter till övriga samhället men har en negativ effekt genom att det fördyrar anskaffningen. En framgångsfaktor gällande svensk försvaranskaffning är svenska modellen som hanterar faktorer kring soft systems engineering väl.
There is relatively little research into defence procurement and its surrounding factors, particularly in a Swedish context. One possible reason could be that development has been rapid and has overtaken theory. This raises interest in studying factors that influence Swedish defence procurement in terms of the selection of whom procurement occurs from. This paper is a qualitative investigative study with an inductive approach, the aim of which is to understand the underlying themes and patterns behind the Swedish procurement process. The paper takes a broad view of the procurement process and, therefore, Hartley’s theory is used, which is built on studies of the UK Ministry of Defence. The empirics consist of in-depth interviews where the respondents represent the Swedish Armed Forces, the Swedish Defence Materiel Administration (FMV) and the Swedish Ministry of Defence. The theory is then used to analyse the empirics, to finally illustrate theoretical as well as practical points of development. The results of this study show that defence policy and economy influence the Swedish procurement process for complex armaments to a large extent. The effects are positive in terms of some positive spin-off effects for the rest of the society, but there are negative effects because it makes procurement more expensive. One success factor for Swedish defence procurement is the Swedish model that effectively deals with factors surrounding soft systems engineering.

Стилі APA, Harvard, Vancouver, ISO та ін.

15

Klipic, Alma, and Sidar Eken. "Techno-Economic Analysis of Small-Scale Polygeneration Systems for a Ground Based Air Defence Operations Center in the Swedish Armed Forces." Thesis, KTH, Kraft- och värmeteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277757.

Повний текст джерела

Анотація:

Climate change is an important topic of today's discussion where scientists have determined that a large proportion of the increasing global temperatures is a product of the increasing greenhouse gases in the atmosphere. Globally it is expected that the share of renewable power generation is set to increase with 50 % between 2019 and 2024. Together with cost reductions and advancements in renewable energy technologies this opens up an opportunity for companies and market actors to reevaluate their power generation systems. By utilising a polygeneration system an energy system is able to combine multiple energy sources to produce several energy services in an efficient, cost effective and sustainable way. This thesis analyses the possibilities of implementing alternative power generation systems for a unit in the Swedish Armed Forces. In close conjunction with the Swedish Armed Forces works The Swedish Defence Material Administration with the primary assignment to procure, develop and deliver equipment and services to the Swedish defence. In this thesis, a Ground Based Air Defence Operations Center is used as a case study which utilises diesel gensets for power generation. The energy system of the unit is analysed as well as the power, heat and cooling demands. Different scenarios based on current and future developments in energy technology are modelled in the microgrid software Homer Pro. The system model 1 for the scenarios BAU, AF1 and AF2 requires no modification of the gensets in the current power generation system. Instead alternative fuel types are modelled where a biodiesel B20 blend is used for AF1 and 1 hydrogenated vegetable oil is used in the AF2 scenario. In the scenarios using the system model 2, FS1 is utilising the current genset upgraded with a heat recovery system running on hydrogenated vegetable oil. The FS2 scenario proposes a microturbine with a capacity of 30 kW as an alternative to the current genset. In the FIFS scenario a PEM fuel cell is modelled, also having a capacity of 30 kW. All of the system model 2 configurations included a battery system, a membrane distiller for water purification and a thermal storage tank as additional units. The main results from the thesis show that all scenarios except for FS2 reduce the annual emissions from the unit. However, this brings a higher net present value for the systems as well as a higher yearly operation cost. The results indicate that the FS1 scenario is able to decrease the CO2 emissions with almost 50 % with adjustments to the current gensets as well as providing the unit with excess heat for water purification and storage in the thermal tank.
Klimatförändringen är ett viktigt ämne idag där forskare har fastställt att en stor andel av ökningen av medeltemperaturen beror på ökade växthusgaser i atmosfären. Globalt förväntas kraftgenerering från förnybara källor att öka med 50 % mellan åren 2019 till 2024. Detta i samband med kostnadsminskningar och framsteg inom förnybara energiteknologier leder till en möjlighet för företag och aktörer att omvärdera sina energisystem. Genom att använda ett polygenereringssystem kan ett energisystem kombinera flera energikällor för att producera fler energitjänster på ett hållbart och kostnadseffektivt sätt. Detta examensarbete undersöker möjligheten att implementera alternativa kraftgenereringssystem för en enhet i Försvarsmakten. I ett nära samarbete med Försvarsmakten arbetar Försvarets Materielverk med det primära uppdraget att upphandla, utveckla och leverera materiel och tjänster till det svenska försvaret. I detta arbete har en luftvärnscentral som nyttjar dieselgeneratorer för kraftproduktion använts som en fallstudie. Enhetens energisystem har analyserats och därtill även el-, värme- och kylbehovet för denna enhet. Olika scenarier baserat på nuvarande och framtida utveckling inom energiteknik har modellerats i microgridprogrammet Homer Pro. För system modellerna 1 i scenarierna BAU, AF1 och AF2 görs inga modifieringar av befintliga system utöver bränsletyp. Scenario AF1 använder en biodieselblandning B20 och i AF2 drivs systemet med vätgasbehandlad växtolja. För modellerna som använder sig utav system modellerna 2 är FS1 ett scenario baserat på en uppgradering av nuvarande kraftenhet genom en värmeåtervinningsenhet. FS2 föreslår en alternativ kraftenhet i form av en mikroturbin med en kapacitet på 30 kW. En PEM-bränslecell är modellerad i scenario FIFS som även den har en kapacitet på 30 kW. Tillhörande komponenter till system modellerna 2 är ett batterisystem, en vattenreningsenhet och en varmvattentank. Resultaten visar att alla scenarier förutom FS2 minskar de årliga utsläppen från enheten. Detta på en bekostnad av en högre nuvärdeskostnad och en högre årlig kostnad för driften av systemen. Från simuleringen visar resultaten även att FS1 kan bidra till att minska utsläppen med nästan 50 % genom justeringar av nuvarande kraftenhet samtidigt som systemet levererar överskottsvärme för vattenrening och lagring i varmvattentanken.

Стилі APA, Harvard, Vancouver, ISO та ін.

16

Philpott, Elaine Josephine Catherine. "Constraints on the implementation of concurrent engineering with suppliers in civil and defence design communities : differentiating design ethos." Thesis, University of Bedfordshire, 2001. http://hdl.handle.net/10547/576456.

Повний текст джерела

Анотація:

Successful Concurrent Engineering (CE) with suppliers requires a pre-disposition on the part of the prime company and the supplier to work in this manner. This thesis explores the impact of design ethos on the implementation of Supplier-inLoop (SIL) CE between an Original Equipment Manufacturer (OEM) and a first tier supplier. Design ethos for the purpose of this thesis is described as 'a characteristic manner or approach to constraints on SIL displayed by personnel involved in the design of new products'. This research employs a mixed-method to understand SIL constraints across industry sectors. A design ethos framework is developed and a military design community is characterised in terms of anomalies to the existing literature. These anomalies are then tested through a questionnaire and then interpreted in terms of the design ethos framework. The results of this comparison show that some characteristics are common to both the civil and military design communities and some are not. A case is made that design ethos, in the context of SIL, is primarily determined by: suppliers' aptitude, skill level and contracts; problems with data I information exchange mechanisms; existing processes, relationships and management support; supplier history; technological view of the product; external influences on the process; existing design milestones; visibility of supplier capability; and, continuity of service in terms of skill and data security. The research concludes that the implementation of SIL is directly impacted by design ethos, and that for SIL to be a success in the military sector design ethos must be managed in line with business objectives. The contribution to knowledge that this thesis provides is the insight it offers into the human issues associated with implementing concurrent engineering with external suppliers, and the identification of sector-specific issues as well as those which will benefit from cross sectoral learning. It is of value to military and civil OEMs for purpose of change management, also to their suppliers in understanding the different needs of military and civil customers when working in a concurrent engmeenng manner.

Стилі APA, Harvard, Vancouver, ISO та ін.

17

Gustafsson, Isabel, and Agnes Rönnblom. "Life Cycle Assessment of a surface radar system : A case study at Saab Electronic Defence Systems." Thesis, Linköpings universitet, Industriell miljöteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-122720.

Повний текст джерела

Анотація:

This master thesis was performed with the main purpose of evaluating the environmental performance of a surface radar system with the means of a life cycle assessment, LCA. Saab Electronic Defence Systems, EDS, was the initiator and driver of the project, and is also owner of the radar system evaluated. Apart from the environmental performance the project was carried out with the intention of EDS wanting to gain knowledge about working with LCA, both in terms of methodology and to get an insight into whether and how well they can work with the tool in their current situation. In order to assess the radar systems environmental impact through its entire life cycle there was emphasis on the use phase since the object can be used in several different ways under various circumstances. Eight different operational profiles were thus addressed in order to compare these variations in use scenarios. In addition, studies were performed on whether there exist any guidelines on how use phase scenarios can or should be defined when conducting an LCA. The LCA was performed in accordance with the ISO 14040 family and the database Ecoinvent has been used for mapping the in- and outflows. To calculate the potential environmental impacts ReCiPé was used, where three out of 18 impact categories were chosen to focus upon in agreement with EDS, namely climate change, fossil depletion and mineral resource depletion. Apart from within some business areas, conclusion could be drawn that no general guidelines exist for the definition of the use phase in an LCA. Besides being described in order to increase transparency in the assessment, no further requirements are set by ISO. Found through the assessment is that the use phase shows a major contribution to the overall environmental impacts from the entire life cycle, by being accountable for roughly 85 %. Depending on impact category, the cause lies with either the radar operation due to its large amount of diesel consumption or with the extraction of materials needed to provide for the replacement of faulty components during maintenance. In accordance with their share of the object’s weight, aluminium, copper and iron stand for about 77 % of the materials environmental impact. Noticeable is though that gold takes place on the top ten list of contributing materials with its 0.0001 % of the total weight, meaning that not only do the large amounts of a material matter, more important is the relation between weight and environmental impact. Regarding the eight operational profiles, out of the two parameters compared the radar operation proved to have significantly larger impacts in all three impact categories than the vehicle operation. Interestingly enough, it was found that if the radar and vehicle would have the same amount of operating hours, the vehicle would have larger impacts than the radar. In conclusion, from an environmental perspective it is more important to keep the vehicle operating hours low. However, since the radar operating hours are high at this point it would make a significant difference in reducing the radar fuel consumption. Lastly, for EDS to be able to continue in working with LCA, conclusions are drawn that a more qualified information base needs to be built up within the organization to avoid as much assumptions as possible, this in order to achieve more reliable results.
Detta examensarbete utfördes med det huvudsakliga syftet att utvärdera miljöprestandan av ett markradarsystem med hjälp av en livscykelanalys, LCA. Saab Electronic Defence Systems, EDS, både tog initiativ till och drev projektet. De är även ägare av det utvärderade markradar-systemet. Utöver miljöprestandan utfördes examensarbetet även med avsikt att bistå EDS med kunskap om att arbeta med LCA, både vad gäller metodiken och för att ge en inblick i om och hur väl de kan arbeta med verktyget under nuvarande förhållanden. För att kunna bedöma radarsystemets miljöpåverkan genom hela dess livscykel lades betoning på användningsfasen då objektet kan användas på ett flertal sätt under olika omständigheter. Åtta olika driftsprofiler sattes därmed upp för att jämföra dessa varierande användnings-scenarier. Dessutom studerades om det idag finns några riktlinjer för hur användningsfasen kan eller bör definieras vid utförandet av en LCA. Analysen utfördes i enlighet med ISO 14040-familjen och databasen Ecoinvent har använts för kartläggning av in- och utflöden. För att beräkna den potentiella miljöpåverkan som uppstår användes ReCiPé, där tre utav 18 miljö-påverkanskategorier valdes att fokusera på, nämligen klimatförändring, fossil utarmning och utarmning av mineraler. Bortsett från några branscher kunde slutsatsen dras att inga generella riktlinjer finns för definitionen av användningsfasen i en LCA. Utöver att beskriva sina val i syfte att öka transparensen i analysen ställs inga ytterligare krav av ISO. Genom att bidra till omkring 85 % av den totala miljöpåverkan visade sig användningsfasen vara överlägsen i förhållande till övriga faser i livscykeln. Beroende på påverkanskategori är den bakomliggande orsaken antingen radardriften, på grund av sin stora mängd dieselförbrukning, eller utvinningen av de ämnen som behövs för utbytet av felaktiga komponenter vid underhåll. I enlighet med deras andel av hela den funktionella enhetens vikt står aluminium, koppar och järn för ungefär 77 % av de utvunna ämnenas miljöpåverkan. Noterbart är dock att guld placerar sig på topp tio-listan över bidragande ämnen med sin andel på 0.0001 % av den totala vikten, vilket innebär att det inte bara är stora mängder av ämnen som spelar roll utan också förhållandet mellan vikt och miljöpåverkan. Vad gäller de åtta driftsprofilerna och dess två ingående parametrar visade sig radardrift ha betydligt större påverkan inom alla tre miljö-påverkanskategorier än fordonsdrift. Anmärkningsvärt nog visade det sig att om radar och fordon skulle ha samma driftstider skulle fordonsdrift bidra med den större miljöpåverkan av de två. Ur miljösynpunkt skulle det därför vara viktigare att hålla fordonets driftstid nere, men eftersom driftstiden för radar i dagsläget är avsevärt högre skulle det göra större skillnad att reducera radarns dieselförbrukning. Slutligen, för att EDS ska kunna fortskrida sitt arbete med LCA, dras slutsatsen att en mer kvalificerad informationsbas måste byggas upp inom organisationen. Detta för att i så hög grad som möjligt kunna undvika antaganden, i syfte att uppnå mer tillförlitliga resultat.

Стилі APA, Harvard, Vancouver, ISO та ін.

18

Morris, Melissa. "Robot Control for Remote Ophthalmology and Pediatric Physical Rehabilitation." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3350.

Повний текст джерела

Анотація:

The development of a robotic slit-lamp for remote ophthalmology is the primary purpose of this work. In addition to novel mechanical designs and implementation, it was also a goal to develop a control system that was flexible enough to be adapted with minimal user adjustment to various styles and configurations of slit-lamps. The system was developed with intentions of commercialization, so common hardware was used for all components to minimize the costs. In order to improve performance using this low-cost hardware, investigations were made to attempt to achieve better performance by applying control theory algorithms in the system software. Ultimately, the controller was to be flexible enough to be applied to other areas of human-robot interaction including pediatric rehabilitation via the use of humanoid robotic aids. This application especially requires a robust controller to facilitate safe interaction. Though all of the prototypes were successfully developed and made to work sufficiently with the control hardware, the application of advanced control did not yield notable gains as was hoped. Further investigations were made attempting to alter the performance of the control system, but the components selected did not have the physical capabilities for improved response above the original software implemented. Despite this disappointment, numerous novel advances were made in the area of teleoperated ophthalmic technology and pediatric physical rehabilitation tools. This includes a system that is used to remote control a slit-lamp and lens for examinations and some laser procedures. Secondly, a series of of humanoid systems suitable for both medical research and therapeutic modeling were developed. This included a robotic face used as an interactive system for ophthalmic testing and training. It can also be used as one component in an interactive humanoid robotic system that includes hands and arms to allow use of teaching sign language, social skills or modeling occupational therapy tasks. Finally, a humanoid system is presented that can serve as a customized surrogate between a therapist and client to model physical therapy tasks in a realistic manner. These systems are all functional, safe and low-cost to allow for feasible implementation with patients in the near future.

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Lundmark, Felix. "Standard and geographical dispersion : A study at the Swedish Defence Materiel Administration." Thesis, Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-69946.

Повний текст джерела

Анотація:

This is the project report for the master thesis project in Industrial design engineering at Luleå University of Technology. The project spanned from January to June 2018. The project took place at the Swedish Defence Materiel Administration (FMV) in the sub-division FSV MarkV. FMV makes sure that Sweden’s defence and military have the proper and functioning equipment, whereas MarkV is responsible for providing services directed towards equipment operated on land. MarkV wanted to implement standard as part of their planned introduction of MarkV Production System (MPS) in 2019. MPS faced the challenge of implementation at several geographically dispersed workshops. This project was therefore carried out to investigate if and how centralized standards could be implemented within their geographically dispersed organization. The project has included visits to the workshops in Boden and Luleå as well as participation at a meeting with the project group developing MPS. However, the project has mainly been conducted from a theoretical standpoint, where literature about this subject has been explored. From the theoretical framework, a requirement specification was compiled. This specification was used to point out the key components to a successful implementation. The result from this project was a model developed to describe how each and every of the key component worked, as well as how MarkV could go about affecting it. The key components in this model was standard, supporting structure, managers and leaders, employees and participation, organizational culture and dealing with resistance. A section in this model was later dedicated to addressing what must be thought of before full roll-out. It was concluded that MarkV can implement centralized standards. However, MarkV must understand that the demands put on the organization will vary between standard and standard work. Standards were also considered less likely to meet contradiction upon implementation compared to standard work. The obstacles to implementation was identified as human resistance and non-human resistance. However, it was also concluded that non-human actors, such as the standard itself and the platform for MPS could possibly facilitate change if properly designed. Identifying the root cause of resistance could contribute to the change process in terms of acting as constructive critique. Using the proposed rule-of-thumb could help MarkV cope with resistance without spending too much energy on convincing employees. For MarkV to maintain and improve standard, it was concluded that they must perform follow-up and constructively use deviations. MarkV has been recommended to use the developed model in their further development of MPS. Practical tips on how to affect individual components has been presented in the model itself as well as in the final recommendation.
Detta examensarbete genomfördes som det sista momentet i civilingenjörsutbildningen Teknisk Design vid Luleå tekniska universitet med inriktning produktionsdesign. Projektet sträckte sig från januari till juni under 2018. Projektet genomfördes hos Försvarets Materielverk (FMV) inom MarkV som är den del av Förråd, Service och verkstäder (FSV). FMV säkerställer att Sveriges försvar och militär har rätt och fungerade materiel. MarkV är ansvariga för att erbjuda tjänster som är riktade mot materiel som opereras på land. MarkV hade som mål att implementera standard i samband med introduktionen av MarkV produktionssystem (MPS) under 2019. Att implementera MPS i MarkV sågs som en utmaning eftersom verksamheten består av 24 stycken geografiskt utspridda markverkstäder. Detta projekt genomfördes för att utvärdera om och hur centraliserade standarder skulle kunna implementeras i deras verksamhet. Projektet inkluderade besök vid markverkstäderna i Boden och Luleå, samt innefattade deltagande vid ett möte med projektgruppen som utvecklar MPS. Projektet har däremot främst genomförts ur ett teoretiskt perspektiv där litteraturen inom detta område har utforskats. Från den teoretiska referensramen sammanställdes en kravspecifikation som identifierade vilka nyckelkomponenter som behöver tas hänsyn till för en framgångsrik implementering. Resultatet från detta arbete var en modell som förklarade hur dessa nyckelkomponenter fungerade, samt förklarade hur MarkV kan påverka dessa. Nyckelkomponenterna som inkluderades i modellen var standard, supporting structure, managers and leaders, employees and participation, organizational culture, dealing with resistance och before full roll-out. Slutsatsen som drogs var att MarkV kan implementera centrala standarder. Kraven som kommer att ställas på MarkV kommer däremot att variera beroende på om implementeringen innefattar standardiserade arbetssätt eller enbart standard. Standardiserade arbetssätt ansågs mer sannolikt att möta motstånd. De två olika typer av motstånd som identifierades var mänskligt och icke-mänskligt motstånd. Slutsatsen kunde även dras att icke-mänskliga aktörer, likt standarden i sig själv samt plattformen för MPS, kan främja förändringsprocessen. Att identifiera rotorsaken till motstånd ansågs kunna bidra konstruktivt till förändringsprocessen. Genom att använda den föreslagna tumregeln kan MarkV bemöta utmaningen med motstånd utan att spendera för mycket energi på att övertala anställda. För att MarkV ska kunna upprätthålla och förbättra standarder kunde det konkluderas att uppföljning och ett konstruktivt nyttjande av avvikelser kommer att vara nödvändigt. MarkV har blivit rekommenderade att använda den utvecklade modellen vid det fortsatta arbetet med att utveckla MPS. Praktiska tips på hur MarkV kan påverka de individuella komponenterna har getts löpande i modellen samt i den avslutande rekommendationen.

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Ling, Jonathan, and Gustav Lindstrand. "Optimizable Hydroponic Plant Incubator : Building a hydroponic plant incubator with a highly optimizable environment." Thesis, KTH, Mekatronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-295805.

Повний текст джерела

Анотація:

This report investigates how to build a compact, optimizable and at the same time user friendly hydroponic systemfor growing plants as efficiently as possible. Hydroponics grows plants using water with dissolved nutrients instead of soil, allowing faster and more efficient growth.The focus has been on the implementation and the usability of such a system, centering around monitoring and to some degree controlling important parameters for growth such as humidity, air temperature, nutrition concentration and light intensity, colour and exposure time. The plant is enclosed in a confined space with artificial lighting which allows thorough control of the light environment. In order to achieve the desired level of control over the growth parameters, several sensors along with a microcontroller were used. A touch screen with a custom built graphical user interface was also connected to allow the user to control and monitor important aspects of growth conditions. The conclusion drawn from this project is that there is ahigh order of optimizability within the boundaries of this project. The measured factors are easily read on an intuitive, easily navigated touch screen for direct feedback. Regarding the lights’ effect on plant growth, the conclusionis drawn that plants grow well with many types of lights, but more time is needed to thoroughly investigate different light exposure times, colour and intensity.
I denna rapport undersöks hur man kan bygga ett kompakt, optimerat och samtidigt användarvänligt hydroponiskt system för att odla växter så effektivt som möjligt. Hydroponiska system får plantor att växa genom att användavatten med näring istället för jord, vilket tillåter snabbare och mer effektiv tillväxt. Fokuset i denna rapport har varit på implementeringen och användbarheten av ett sådant system, med tyngpunkt på övervakning och till viss grad styrning av viktiga faktorer i en plantas tillväxt såsom luftfuktighet, temperatur, näringskoncentration och ljusintensitet, färg och exponeringstid. Växten är innesluten i ett begränsat utrymme med artificiellt ljus, vilket tillåter genomgående kontroll av ljusmiljön. För att uppnå önskad kontroll av tillväxtparametrarna, användes ett flertal sensorer tillsammans med en mikrokontroller. Till detta kopplades en pekskärm med ett egen tillverkat användargränssnitt, som tillåter användaren att kontrollera och övervaka viktiga aspekter i tillväxten. Slutsatsen från detta projekt är att det finns en hög grad av optimerbarhet inom denna konstruktion. De uppmätta parametrarna kan enkelt avläsa ljusexponering, ljusintesitet och färg.

Стилі APA, Harvard, Vancouver, ISO та ін.

21

VALKO, ABEL. "Relay Attack Resistant Passive Keyless Entry : Securing PKE Systems with Immobility Detection." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279839.

Повний текст джерела

Анотація:

A significant security risk of modern vehicles is their vulnerability to relay attacks, due to challenge-response methods, such as those employed in Passive Keyless Entry (PKE) used by most commercial cars, being inherently exposed. This class of attacks are where communication between a vehicle and its key is relayed by an attacker over long range - thereby bypassing any encryption and unlocking the vehicle without requiring direct access to the key. While a multitude of defenses have been proposed in recent years, many lack either robustness or practicality. Any viable system will likely have to rely on an environmental parameter which is not easily manipulated. Moreover, the system has to be: cost effective; easily implementable; and take user comfort, such as the key’s battery life, into account. This thesis implements and evaluates a PKE system resistant to relay attacks, analyses a multitude of proposed strategies in literature for feasibility, as well as suggests a novel method: Approach Curve Matching. It is concluded that the most promising strategies are: Immobility Detection, Distance Bounding Protocols, and Approach Curve Matching - the first of which is chosen to be implemented in the prototype PKE system. The project develops a PKE system and implements the communication protocol using Bluetooth, as opposed to the conventional RFID. Immobility Detection, using an accelerometer, is then implemented. The final system is then tested and evaluated. It is concluded that while Immobility Detection is not comprehensively effective, it is easily implementable, cost-effective, and can greatly increase the security of PKE systems. Finally, it is proposed that Immobility Detection should be employed promptly by manufacturers while investigating potentially more effective, albeit uncertain, strategies.
En betydande säkerhetsbrist av moderna fordon är deras sårbarhet mot så kallade ’relay attacker’. Dessa typer av attacker, där signaler mellan bilen och nyckeln vidarebefordras, kringgår all kryptering och låser upp bilen utan att ha direkt tillgång till nyckeln. En stor del av kommersiella fordon tillämpar ’Passive Keyless Entry’ (PKE) som bygger på ’challenge-response’ metoder som visats vara särskilt utsatta för dessa attacker. En mängd olika skyddssystem har föreslagits på senare år, men många saknar erforderlig robusthet eller genomförbarhet. Ett lämpligt system bör uppfylla en rad olika kriterier. Strategin måste grundas på en omgivningsparameter som är både oföränderlig och tillräckligt rymdberoende att två nära positoner kan skiljas åt. Dessutom ska systemet vara kostnadseffektivt, implementerbart, och ta hänsyn till användarkomfort såsom batteritid. Projektets huvudsyfte är konstruktionen och analysen av ett ’relay attack’ resistent PKE system. I detta projekt ingår också en analys av ett antal föreslagna försvar och ett förslag om en ny metod: ’Approach Curve Matching’. Slutsatsen dras att de mest lovande taktikerna är: analys av Jaccard indexet av Wi-Fi hotspots, ’Distance Bounding Protocols’, ’Approach Curve Matching’ och ’Immobility Detection’ som också implementeras i prototyp PKE systemet. Projektet utvecklar först ett PKE system med två Raspberry Pis som agerar som bilens och nyckelns mikrodatorer och implementerar kommunikationsprotokollet med hjälp av Bluetooth. ’Immobility Detection’ är sedan implementerad genom en inbyggd accelerometer i nyckeln. Slutligen testas och utvärderas systemet. Det konkluderas att trots att ’Immobility Detection’s effektivitet inte är helt omfattande är den lätt att implementera, kostnadseffektiv, och kan bidra till en betydlig ökning av säkerheten hos PKE system. Vidare observerade projektet att Bluetooths ’Received Signal Strength Indicator’ (RSSI) mätningar är utsatta för avsevärd ostadighet och är allmänt omgivningsberoende. Därför anses Bluetooth RSSI inte lämplig för PKE tillämpningar även om andra metoder för avståndsmätning med Bluetooth kan ha högre prestanda. Det föreslås att ’Immobility Detection’ tillämpas av tillverkare omgående medans andra potentiellt mer effektiva strategier utreds.

Стилі APA, Harvard, Vancouver, ISO та ін.

22

Zaitouni, Wael K. "Applied Real-Time Integrated Distributed Control Systems: An Industrial Overview and an Implemented Laboratory Case Study." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc862854/.

Повний текст джерела

Анотація:

This thesis dissertation mainly compares and investigates laboratory study of different implementation methodologies of applied control systems and how they can be adopted in industrial, as well as commercial, automation applications. Namely the research paper aims to assess or evaluate eventual feedback control loops' performance and robustness over multiple conventional or state-of-the-art technologies in the field of applied industrial automation and instrumentation by implementing a laboratory case study setup: the ball on beam system. Hence, the paper tries to close the gap between industry and academia by: first, conducting a historical study and background information of main evolutional and technological eras in the field of industrial process control automation and instrumentation. Then, some related basic theoretical as well as practical concepts are reviewed in Chapter 2 of the report before displaying the detailed design. After that, the next Chapter, analyses the ball on beam control system problem as the case studied in the context of this research through reviewing previous literature, modeling and simulation. The following Chapter details the proposed design and implementation of the ball on beam case study as if it is under the introduced distributed industrial automation architecture. Finally, Chapter 5 concludes this work by listing several points leaned, remarks, and observations, and stating possible development and the future vision of this research.

Стилі APA, Harvard, Vancouver, ISO та ін.

23

GHATTAS, HELEN. "Managing complex product development projects : An analytical framework for complex product development." Thesis, KTH, Industriell Management, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191093.

Повний текст джерела

Анотація:

Under de senaste åren har produkterna blivit mer invecklade beträffande anslutningen, prestanda och funktionalitet. Därför är syftet av denna studie att undersöka hur komplexa system utvecklas och leds genom att genomföra fallstudie på olika svenska företag som utvecklar mekatroniska och cyber-fysiska system. Resultatet av denna studie har lett till identifieringen av många utmaningar som de undersökta företagen har och som i sin tur har lett till framställningen av ett analytiskt ramverk som diskuterar hur och vad man bör göra för att utveckla komplexa produkter på ett effektivt sätt, så att onödig komplexitet i produktutvecklingen kan reduceras.
In recent years, products have become more complex in terms of connectivity, performance and functionality. Therefore, this study aims at studying how complex products are developed and managed through conducting multiple case studies at different Swedish companies that develop mechatronic or cyberphysical systems. The results of this study is the identification of many challenges that the investigated companies have, which have led to a presentation of an analytical framework that discusses how complex product development projects can and should be managed in order to be efficient, in order to reduce unnecessary complexity in the way companies develop these complex products.

Стилі APA, Harvard, Vancouver, ISO та ін.

24

Chan, Darren Michael. "Telepresence: Design, Implementation and Study of an HMD-controlled Avatar with a Mechatronic Approach." DigitalCommons@CalPoly, 2015. https://digitalcommons.calpoly.edu/theses/1395.

Повний текст джерела

Анотація:

Telepresence describes technologies that allow users to remotely experience the sensation of being present at an event without being physically present. An avatar exists to represent the user whilst in a remote location and is tasked to collect stimuli from its immediate surroundings to be delivered to the user for consumption. With the advent of recent developments in Virtual Reality technology, viz., head-mounted displays (HMDs), new possibilities have been enabled in the field of Telepresence. The main focus of this thesis is to develop a solution for visual Telepresence, where an HMD is used to control the direction of a camera‟s viewpoint, such that the user‟s head is tracked by the avatar, while providing visual feedback to the user. The design and development of the device follows a mechatronic approach, where a real time operating system (RTOS) is used in conjunction with a microcontroller for mechanical actuator control. The first-generation prototype, HOG-1 (HMD-Operated Gimbal, rev. 1), developed for this thesis serves as a foundation for study; the implementation and analysis of the prototype contributes to the state of the art by providing a clearer glimpse of hardware and software requirements that are necessary to construct an improved model. Additionally, qualitative and quantitative measurements are developed in the process of this research.

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Hasp, Frank Alexander, and Morgan Tjernström. "Construction and theoretical study of a ball balancing platform : Limitations when stabilizing dynamic systems through implementation of automatic control theory." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264486.

Повний текст джерела

Анотація:

Control theory and its applications are crucial when operating within the area of dynamic systems. Compensating for disturbances and external actions imposed on a given system being inherently unstable or semi-stable. Through the physical construction of a apparatus as a demonstrator of the theory further comparing the factual physical and computer simulated results derived from Newtonian mechanics. To enable comparison, designing a satisfactory controller capable of fulfilling the requirements set for the system is necessary. With regards to apparatus and control, the introduction of a proportional-integralderivative controller for a system balancing a ball on a platform. Further allowing for analysis to determine the limitations when stabilizing a naturally unstable or semi-stable system. Also, examine how these dier from the theoretical expectations. The control applied throughout the thesis is of the type linear, exclusively being able to operate properly within the linear spectrum of control. Using standard components and a microcontroller, a apparatus is constructed to maintain a ball on a platform. This is executed through programming with Arduino libraries and open source code. Hence, for research purposes, to see if the apparatus can operate satisfactory within the linear domain of control. With the aforementioned stated, this thesis will first cover the theoretical model of the ball on platform scenario through computer aided programs. Then compare the theoretical results with the results acquired from a physical construction. Further examine why dierences occur considering control theory and system implementation.
Reglertekniken och dess applikationer är centrala för att kontrollera dynamiska system och möjliggör för kompensering av störningar i system som är naturligt instabila eller semistabila. Genom konstruktion av en apparat som demonstrerar reglerteknisk teori kan vidare jämförelser mellan resultat från apparaten och datorsimuleringar, erhållna från Newtonsk mekanik, tillhandahållas. Syftet är vidare att utveckla en regulator som uppfyller de krav som sätts upp för systemet. Med hänsyn till apparaten och regulatorn, introduceras en proportionell-integrerande-deriverande regulator för en bollbalanserande plattform. På så sätt kan begränsningarna vid stabilisering av ett naturligt instabilt eller semistabilt system bestämmas. Vidare studeras hur dessa skiljer sig från de teoretiska förväntningarna. Endast linjär kontroll kommer att användas i detta projekt, därav en apparat som enbart är välfungerande inom ett linjärt domän. Genom användning av standardkomponenter och en mikrokontroll konstrueras en apparat för att bibehålla en boll på en plattform. Detta möjliggörs genom programmering med Arduinos bibliotek och öppen källkod. Således är, ur forskningssynpunkt, anordningens förmåga att fungera väl inom den linjära domänen av intresse. Utifrån detta kommer examensarbetet först att redogöra för den teoretiska modellen av en boll balanserande på en plattform genom användandet av datorprogram. För att sedan jämföra de teoretiska resultaten med de resultat som erhålls från den fysiska bollbalanserande konstruktionen. Vidare undersöks varför skillnader uppstår med hänsyn till reglerteknik och systemimplementering

Стилі APA, Harvard, Vancouver, ISO та ін.

26

Qamar, Ahsan. "An Integrated Approach towards Model-Based Mechatronic Design." Licentiate thesis, KTH, Mekatronik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-35374.

Повний текст джерела

Анотація:

Mechatronic design is an enigma. On the one hand, mechatronic products promise enhanced functionality, and better performance at reduced cost. On the other hand, optimizing mechatronic design concepts is a major challenge to overcome during the design process. In the past, less attention has been paid to the life phases of a mechatronic product, and it was assumed that modifications in electronics and software will ensure that the product performs to expectation throughout its life time. However it has been realized that introducing design changes in mechatronics is not easy, since it is difficult to assess the consequences of a design decision, both during the design process of a new product, and during a design modification. It is also realized that there is a strong need to consider the product's life phases during the early phases of product development. Furthermore, it is rather difficult to perform a design optimization since it requires introducing changes across different domains, which is not well supported by the methods and tools available today. This thesis investigates the topic of mechatronic design and attacks some of the major challenges that have been identified regarding the design of mechatronic products. The goal is to provide support to the designers to facilitate better understanding of the consequences of their design choices as early as possible. The work also aims to provide support for assessing alternative design concepts, and for optimizing a design concept based on requirements, constraints and designer preferences at the time of design. The thesis highlights three main challenges related to mechatronic product development: the need for a common language during conceptual design; the inadequate information transfer between engineering domains; and the difficulty in assessing the properties of competing mechatronic concepts. A model-based integration approach is presented, and these key challenges are considered in relation to an integrated modeling and design infrastructure. The approach is illustrated through the design of two mechatronic systems- a two degrees-of-freedom robot, and a hospital bed propulsion system. Initial results provide evidence of good potential for information transfer across mechatronic domains. Although SysML was used for the case studies, some important questions were raised about its suitability as a common language for mechatronics. Suggestions for future work are: to utilize the developed infrastructure and incorporate a capability to model and assess consequences of competing design concepts; provide support for optimizing these concepts; and evaluate the usefulness of the developed infrastructure in a real-world design setting. These efforts should provide ample information to the designer for making adequate decisions during the design process.
QC 20110629

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Omerdic, Edin. "Thruster fault diagnosis and accommodation for overactuated open-frame underwater vehicles." Thesis, University of South Wales, 2004. https://pure.southwales.ac.uk/en/studentthesis/thruster-fault-diagnosis-and-accommodation-for-overactuated-openframe-underwater-vehicles(d010b243-e2ee-4a12-9ff0-037c9e1af958).html.

Повний текст джерела

Анотація:

The work presented in the thesis concerns the design and development of a novel thruster fault diagnosis and accommodation system (PDAS) for overactuated, open-frame underwater vehicles. The remotely operated vehicles (ROVs) considered in this thesis have four thrusters for motion in the horizontal plane with three controllable degrees of freedom (DoF). Due to the redundancy resulting from this configuration, for the case of a partial fault or a total fault in a single thruster it is possible to reallocate control among operable thrusters in order that the ROV pilot is able to maintain control of the faulty ROV and to continue with missions. The proposed PDAS consists of two subsystems: a fault diagnosis subsystem (FDS) and a fault accommodation subsystem (FAS). The FDS uses fault detector units to monitor thruster states. Robust and reliable interrogation of thruster states, and subsequent identification of faults, is accomplished using methods based on the integration of selforganising maps and fuzzy logic clustering. The FAS uses information provided by the FDS to perform an appropriate redistribution of thruster demands in order to accommodate faults. The FAS uses a hybrid approach for control allocation, which integrates the pseudoinverse method and the fixed-point iterations method. A control energy cost function is used as the optimisation criteria. In fault-free and faulty cases the FAS finds the optimal solution, which minimises this criteria. The concept of feasible region is developed in order to visualise thruster velocity saturation bounds. The PDAS provides a dynamic update of saturation bounds using a complex three-dimensional visualisation of the feasible region (attainable command set), such that the ROV pilot is informed with the effects of thruster fault accommodation, incorporated in the new shape of the attainable command set. In this way the ROV pilot can easy adapt to newly created changes and continue the mission in the presence of a fault. The prototype of the PDAS was developed in the MATLAB environment as a Simulink model, which includes a nonlinear model of an ROV with 6 DOF, propulsion system and a hand control unit. The hand control unit was simulated in hardware using a joystick as input device to generate command signals. Different fault conditions are simulated in order to investigate the performance of the PDAS. A virtual underwater world was developed, which enabled tuning, testing and evaluation of the PDAS using simulations of two underwater vehicles (FALCON, Seaeye Marine Ltd. and URIS, University of Girona) in a 'realistic' underwater environment. The performance of the PDAS was demonstrated and evaluated via tank trials of the FALCON ROV in QinetiQ Ocean Basin Tank at Haslar, where the existing control software was enhanced with the PDAS algorithm. The results of real-world experiments confirmed the effectiveness of the PDAS in maintaining vehicle manoeuvrability and in preserving the vehicle mission in the presence of thruster faults.

Стилі APA, Harvard, Vancouver, ISO та ін.

28

Wilmsen, Miriam, Markus Spadinger, Albert Albers, Cong Minh Nguyen, and Jonas Heimicke. "Iterationsarten und deren Auslöser in der Frühen Phase der PGE – Produktgenerationsentwicklung." Thelem Universitätsverlag & Buchhandlung GmbH & Co. KG, 2019. https://tud.qucosa.de/id/qucosa%3A36960.

Повний текст джерела

Анотація:

Insbesondere die frühen Phasen in Prozessen der Mechatroniksystementwicklung sind durch ein hohes Maß an Unsicherheit gekennzeichnet. Zu diesem Zeitpunkt des Produktentstehungsprozesses liegen lediglich vage und unscharfe Anforderungen an das Produkt vor, welche es zu konkretisieren gilt. Aktuelle Herausforderungen der Produktentwicklung haben einen verstärkenden Effekt auf die Unsicherheiten in frühen Entwicklungsphasen. Diesen begegnen Unternehmen aus dem Bereich der Mechatroniksystementwicklung zunehmend mit der Implementierung agiler Entwicklungsansätze in ihre etablierten Prozesse. Neben der frühen und kontinuierlichen Kundeneinbindung, der klare Ausrichtung der Prozesse auf die Wertsteigerung der Produkte aus Kundensicht, flachen und offenen Hierarchien und dem stetigen Aufbau und Weiterentwicklung von Prototypen verleihen meist geplante Iterationen den jeweiligen Projekten das Adjektiv „agil“. Die Vielfalt der in der Literatur beschriebenen und meist generisch formulierten Arten von Iterationen (geplant oder ungeplant, korrekturbezogen oder progressiv) ist jedoch sehr groß. Zudem werden Iterationen in der Praxis meist intuitiv und unbewusst durchgeführt, was zum einen dazu führt, dass das jeweilige Entwicklungsvorgehen nicht situationsoptimal ausgeführt wird oder gar hinsichtlich der Ergebnissynthese und –Analyse redundante Tätigkeiten erfolgen. Aus diesem Grund verfolgt das vorliegenden Forschungsvorhaben die Zielsetzung, einen Beitrag zur Unterstützung der Produktentwickler in frühen Entwicklungsphasen bei der Identifikation notwendiger Iterationen zu leisten. Durch eine Berücksichtigung dieser in der kurz- und mittelfristigen Projektplanung kann somit die Prozessunsicherheit reduziert werden.

Стилі APA, Harvard, Vancouver, ISO та ін.

29

Fabbri, Riccardo. "Conceptualization, design & simulation of a small asteroid probe." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

Знайти повний текст джерела

Анотація:

The Asteroid Impact and Deflection Assessment (AIDA), is an upcoming mission resulting from the collaboration of ESA and NASA and aims at assessing the effects of a kinetic impact on an asteroid for the purpose of threat mitigation. In this framework, this research seeks to prove the feasibility of a small lander design able to autonomously land on the secondary object of the asteroid system Didymos. Initially, an overview of the most suitable guidance laws and sensors is provided. This highlighted that some types of proportional navigation guidance laws and the ZEM/ZEV could be good candidates and are therefore further analyzed in the following chapters. Meanwhile, a set of sensors comprising altimeter, camera, Star-Tracker and accelerometers was considered. To assess the effect of the noise affecting the sensors on the translational dynamics of the probe, the system is linearized and studied. This permitted to highlight that the most relevant disturbances are the ones that affect the determination of the LOS rate, hence the readings of camera and star-tracker. Afterward, the deployment is simulated in the details in a simulator, this permitted to determine that a combination of a modified version of the true proportional navigation and ZEM/ZEV provide a good solution in terms of guidance laws. Unfortunately, because of the lack of details characterizing the asteroid model, it was not possible to realistically simulate the ZEM/ZEV. Therefore, it is suggested as the next step of study to carry out further investigation and to develop a simulator able to reach the depth of details required. Finally, a proposed set-up of sensors is delineated and a Monte-Carlo run analyzing the robustness and reliability of this design for the MTPN is reported. The outcome seems to demonstrate that with a very compact and simple design, the probe is capable to autonomously insert itself in a trajectory leading from the deployment location to the target asteroid.

Стилі APA, Harvard, Vancouver, ISO та ін.

30

Skvorchevsky, Alexander Evgenievich. "Modern requirements for electrohydraulic drives of combat and civilian vehicles." Thesis, Національний технічний університет України "Київський політехнічний інститут"; Механіко-машинобудівний інститут, 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/28264.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Ekström, Sebastian. "Bärbar sensorhandske med force feedback för manövrering av en humanoid robothand - : Implementering med monterade sensorer och motorer för styrning och känsel." Thesis, Linnéuniversitetet, Institutionen för fysik och elektroteknik (IFE), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-86116.

Повний текст джерела

Анотація:

The goal of this thesis was to create a sensors glove with force feedback feeling when operating a humanoid robot hand. The development covered multiple areas such as mechanics, electronics and programming. The final product gave the user control over three fingers of a humanoid robotic hand. In the case where the robotic hand comes in contact with an object the user's finger movement is limited according to the pressure the robotic hands fingers exposes the object to.
Rapporten beskriver arbetet för framtagandet och skapandet av en sensorhandske med inbyggd force feedback funktion som därmed ska möjliggöra styrning över en mekanisk gripare med hög finmotorik. Detta för att kunna få en mer realistisk manövrering över griparen. Projektet är uppdelat i två system. Ett system för sensorhand som med en Arduino Uno Rev 3 styr servomotorer som används för att återskapa force feedbacken. Utöver det sker även mätning och analys av användarens fingerposition genom potentiometrar. Det andra systemet är för en humanoid robothand som även den använder sig av en Arduino Uno Rev 3 för att manövrera de servomotorer som handen använder för att flytta fingrarna. Mätning och analys av trycksensorer på robothandens fingertoppar genomförs för att möjliggör återskapandet av force feedback till användaren efter det tryck robothanden utsätter ett objekt för. De två systemen använder sig av ett I2C protokoll i form av multimaster and slave struktur för att kommunicera mellan det två mikrokontrollerna samt deras respektive servomotordrivarkretsar (Adafruit- PCA9685). För att undvika krockar i kommunikationen då mer än en master använder I2C linorna skapades en ovanpåliggande struktur för att upprätta regler för hur kommunikationen ska genomföras. All datahantering och kommunikation programmeras i C++. Programmeringskoden är skapad så att utbytet av robothanden och dess servodrivarkrets är möjligt. Sensorhandsken kan därmed implementeras till vad användaren väljer att använda den till, så länge kommunikationen sker med samma regler och struktur som upprättats. Utöver elektronik och programmering har även mycket mekanik tillämpats då olika delar av elektroniken ska byggas in och kunna fungera korrekt med rörliga mekaniska delar. Detta har bland annat använts i skapandet för fingerpositionsmätningen där trimpotentiometrar har byggts in och rörliga delar kan ändra på det resistiva motståndet i komponenten. Trots projektets begränsning till tre fingrar tyder projektet på att det framtagna konceptet av en sensorhandske med force feedback är fullt möjligt och genomförbart.

Стилі APA, Harvard, Vancouver, ISO та ін.

32

Bricogne-Cuignières, Matthieu. "Méthode agile pour la conception collaborative multidisciplinaire de systèmes intégrés : application à la mécatronique." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2176/document.

Повний текст джерела

Анотація:

Ces travaux portent sur la conception multidisciplinaire de systèmes intégrés. Ces systèmes sont soumis à un nombre d’exigences toujours croissant, entraînant des besoins en termes d’intégration fonctionnelle et spatiale. Ces différents types d’intégration relative au produit sont également la source d’une complexité organisationnelle, provenant à la fois de la multitude d’acteurs réalisant différentes activités d’ingénierie, mais également de la diversité des domaines impliqués, désignée dans ce manuscrit par « intégration multidisciplinaire ». Pour favoriser cette intégration multidisciplinaire, les phases de « conception préliminaire » et de « conception détaillée » ont été identifiées comme déterminantes, notamment car elles se caractérisent par la collaboration de nombreux experts, manipulant un grand nombre de données techniques de définition. Les systèmes conçus lors de conceptions multidisciplinaires restent faiblement intégrés. Cela est en partie dû au cloisonnement entre les disciplines et à un mode d’organisation projet basé sur une planification prédominante, caractérisé notamment par une diffusion de l’information principalement descendante (top-down). Afin d’assurer une meilleure collaboration entre ces différentes disciplines, de permettre des prises de décision éclairées par des indicateurs opérationnels et de pouvoir analyser et mieux comprendre les phénomènes d’intégration des expertises, l’introduction d’une méthode inspirée des principes fondateurs des méthodes agiles est proposée pour la conception collaborative de systèmes intégrés.La contribution de ces travaux s’appuie sur trois concepts complémentaires. Le premier, intitulé Collaborative Actions Framework correspond à un cadre de collaboration opérationnelle autour d’actions. Un des objectifs de ce framework est de faciliter la collaboration des acteurs des projets de conception, quelle que soit leur origine disciplinaire, mais également d’assurer une traçabilité entre les prises de décision et les corrections/modifications apportées sur les données techniques. Cette traçabilité est rendue possible grâce aux liens existants avec le second concept intitulé Workspace. Apportant un nouvel éclairage sur les possibilités offertes par la collaboration autour de ces espaces de collaboration, ce concept offre un certain nombre de possibilités,notamment la mise en commun continue des travaux, l’intégration multidisciplinaire et la validation des modifications. Les échanges de données techniques entre les workspaces, ou le travail simultané sur les mêmes données techniques, s’appuient quant à eux sur la possibilité de pouvoir gérer de façon parallèle différentes versions d’une même donnée technique. Ces possibilités sont proposées par le troisième concept, intitulé branch & merge, qui permet également à différents acteurs de travailler simultanément sur les mêmes données. Enfin, ces trois concepts sont ensuite illustrés par l’intermédiaire d’un démonstrateur composé d’un scénario et d’un prototype informatique. Un produit mécatronique, combinaison synergique et systémique de la mécanique, de l'électronique et de l'informatique temps réel, est utilisé afin d’illustrer les possibilités offertes par nos travaux en termes d'intégration multidisciplinaire lors de la conception collaborative
This work focuses on the multidisciplinary and collaborative design of integrated systems. These systems are subject to an ever increasing number of requirements, leading to the need for more comprehensive functional and spatial integration. These different types of product integration are also at the origin of organizational complexity. This complexity arises not only from the great number of actors performing various engineering activities but also from the diversity of disciplines involved (designated in this manuscript as “multidisciplinary integration”). To encourage this multidisciplinary integration, “preliminary design” and “detailed design” have been identified as the most significant steps, especially since they are characterized by the collaboration of multiple experts handling a large number of product definition’ technical data. Systems that have been designed thanks to multidisciplinary approaches are generally poorly integrated. This is partially due to the compartmentalization of disciplines, as well as to the “project-planned” method, where project planning is predominant and information is mainly spread out “top-down”. To ensure better cooperation between the various disciplines, to enable decision making based on operational indicators and to analyze and understand the multidisciplinary integration processes, a method inspired by the founding principles of agile methods (the agile manifesto) is proposed for the collaborative design of integrated systems. This work is based on three complementary concepts. The first is, the Collaborative Actions Framework, an operational framework for collaboration around actions. One objective of this framework is to improve the collaboration among designers, whatever their disciplinary origin. It also ensures traceability between decision making and corrections/changes made to technical data. This traceability is made possible by the useof the second concept, called Workspace. Even if this term is already well known, we propose a new definition/usage to transform it into collaboration spaces. This concept offers great possibilities, including the continuous delivering/sharing of experts’ contributions, multidisciplinary integration and change validation. The exchange of technical data between workspaces, or simultaneous work on the same data, relies on the ability to manage several parallel versions of the same item into a single datamanagement system. These opportunities are offered by the third concept, called Branch & Merge. Finally, these three concepts are illustrated through a scenario and a computer prototype. A mechatronic product, “the synergistic combination of mechanical and electrical engineering, computer science, and information technology” (Harashima et al., 1996), is used to illustrate the opportunities offered by our work in terms of multidisciplinary integration during collaborative design

Стилі APA, Harvard, Vancouver, ISO та ін.

33

McLucas, Alan Charles Civil Engineering Australian Defence Force Academy UNSW. "An investigation into the integration of qualitative and quantitative techniques for addressing systemic complexity in the context of organisational strategic decision-making." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Civil Engineering, 2001. http://handle.unsw.edu.au/1959.4/38744.

Повний текст джерела

Анотація:

System dynamics modelling has been used for around 40 years to address complex, systemic, dynamic problems, those often described as wicked. But, system dynamics modelling is not an exact science and arguments about the most suitable techniques to use in which circumstances, continues. The nature of these wicked problems is investigated through a series of case studies where poor situational awareness among stakeholders was identified. This was found to be an underlying cause for management failure, suggesting need for better ways of recognising and managing wicked problem situations. Human cognition is considered both as a limitation and enabler to decision-making in wicked problem environments. Naturalistic and deliberate decision-making are reviewed. The thesis identifies the need for integration of qualitative and quantitative techniques. Case study results and a review of the literature led to identification of a set of principles of method to be applied in an integrated framework, the aim being to develop an improved way of addressing wicked problems. These principles were applied to a series of cases in an action research setting. However, organisational and political barriers were encountered. This limited the exploitation and investigation of cases to varying degrees. In response to a need identified in the literature review and the case studies, a tool is designed to facilitate analysis of multi-factorial, non-linear causality. This unique tool and its use to assist in problem conceptualisation, and as an aid to testing alternate strategies, are demonstrated. Further investigation is needed in relation to the veracity of combining causal influences using this tool and system dynamics, broadly. System dynamics modelling was found to have utility needed to support analysis of wicked problems. However, failure in a particular modelling project occurred when it was found necessary to rely on human judgement in estimating values to be input into the models. This was found to be problematic and unacceptably risky for sponsors of the modelling effort. Finally, this work has also identified that further study is required into: the use of human judgement in decision-making and the validity of system dynamics models that rely on the quantification of human judgement.

Стилі APA, Harvard, Vancouver, ISO та ін.

34

Motepe, Sibonelo. "Software integration for human detection in mining UAV systems." Thesis, 2013. http://hdl.handle.net/10413/10407.

Повний текст джерела

Анотація:

Mining is one of the main economic sectors in South Africa. Mining activity contains hazards such collapsing of structures, presence of dangerous gases, accidental explosions and fires. Even though most of these hazards are identified and minimized sometimes accidents occur. These accidents lead to human injuries, direct fatalities and fatalities resulting from delays in victims getting medical attention as a result of delays in search and rescue missions. The rescue missions in underground mines present challenges where rescuers are not sure which locations are victims in, what the area conditions like in the rescue path. A quad rotor unmanned aerial vehicle (UAV) for search and rescue missions is presented. The UAV is controlled from a remote location over Wi-Fi. The communication allows data relay to the ground control station. The communication system is tested on the university’s Wi-Fi network. The UAV also contains a vision system that contains a human detection algorithm to give an indication of human presence to rescuers. The human detection system is based on Haar- Cascade classifiers. The model developed was found to have a false alarm rate of 5×10-3% after training. The model was further tested on streaming data and the overall average positive human detection was found to be 97 %. In the same tests overall false average detection was found to be 2.5 %. The video feed is streamed from the UAV to the ground station (GS) and the flight control instructions are sent to the UAV from the GS via Wi-Fi.
Thesis (M.Sc.Eng)-University of KwaZulu-Natal, Durban, 2013.

Стилі APA, Harvard, Vancouver, ISO та ін.

35

Stier, Jochen. "Geometry-driven petri nets and a method for modelling mechatronic control systems." Thesis, 2006. http://hdl.handle.net/1828/2116.

Повний текст джерела

Анотація:

The development process of mechatronic control systems often relies on physical prototypes to test the interactions between the control software and mechanical components. However, the logistics of synchronizing a concurrent development process and the risks of integrating only partially completed sub-systems often limits effective prototyping. The consequent lack of feedback can lead to overly complex and unreliable systems which may have to undergo expensive re-designs. The interactions between mechanical systems and control software can also be recreated artificially by combining a hybrid modelling language with computer graphics technology. A dynamic 3D environment can generate sensor telemetry for input to a control system, which in turn alters the state of the environment through virtual actuators. This kind of simulation allows engineers to explore a larger design space early during the development process without committing significant resources to physical prototypes. This dissertation introduces a method for simulating mechatronic systems using Petri Nets and Scene Trees. The following chapters formally define the modelling language and illustrate the software architecture and user interface of a novel simulation development environment. The research is validated through qualitative reasoning and by demonstrating a simulation that detects design flaws in a mechatronic system which may have otherwise lead to expensive redesigns in the physical system.

Стилі APA, Harvard, Vancouver, ISO та ін.

36

Potgieter, Johan-Gerhard. "Modular mechatronic CIM control for Internet manufacturing." Thesis, 2002. http://hdl.handle.net/10413/4814.

Повний текст джерела

Анотація:

Mechatronics encompass a holistic approach to the design, development, production, maintenance and disposal of complex engineering systems, products and processes. The control and modelling of the manufacturing process are carried out in a networked environment allowing for realistic real time control and simulation. This is achieved through the declarative definition of Computer Integrated Manufacturing (CIM) components, the standardisation of CIM interfaces and the object-orientated approach to model development and data management. The development ofthe Modular Mechatronic CIM control system is aimed at intelligently scheduling, controlling and monitoring manufacturing processes in realtime over Internet capable networks. Modular Mechatronics is an alternative design approach that requires the decomposition of a project into separate modules, identifiable by their individual mechatronic functionality. Modular Mechatronic control for Internet manufacturing produces an efficient and effective solution for CIM processes. This approach allows a remote user to monitor and control CIM processes in real time over the Internet allow for a supervisory control structure to control and manage these processes. The modular mechatronic design approach has been applied to the development of the CIM Internet control system, to optimise the overall function ofthe CIM system. A flexible, low cost Modular Mechatronic design approach was used to develop the CIM architecture and computer interface network, which served as the backbone of the Modular Mechatronic CIM control system. The modular designed control system was used to control CIM components in real time over the Internet. The Modular Mechatronic building block development allows for future integration of other CIM components.
Thesis (M.Sc.Eng.)-University of Natal, Durban, 2002.

Стилі APA, Harvard, Vancouver, ISO та ін.

37

"A mechatronic approach to develop the concept of a materials handling system for a reconfigurable manufacturing environment." Thesis, 2010. http://hdl.handle.net/10413/1552.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

38

(10716315), Vaibhav Kailas Ahire. "PHYSICS-BASED DIESEL ENGINE MODEL DEVELOPMENT CALIBRATION AND VALIDATION FOR ACCURATE CYLINDER PARAMETERS AND NOX PREDICTION." Thesis, 2021.

Знайти повний текст джерела

Анотація:

Stringent regulatory requirements and modern diesel engine technologies have engaged automotive manufacturers and researchers in accurately predicting and controlling diesel engine-out emissions. As a result, engine control systems have become more complex and opaquer, increasing the development time and costs. To address this challenge, Model-based control methods are an effective way to deal with the criticality of the system study and controls. And physics-based combustion engine modeling is a key to achieve it. This thesis focuses on development and validation of a physics-based model for both engine and emissions using model-based design tools from MATLAB & Simulink. Engine model equipped with exhaust gas circulation and variable geometry turbine is adopted from the previously done work which was then integrated with the combustion and emission model that predicts the heat release rates and NO_xemission from engine. Combustion model is designed based on the mass fraction burnt from CA10 to CA90 and then NO_xpredicted using the extended Zeldovich mechanism. The engine models are tuned for both steady state and dynamics test points to account for engine operating range from the performance data. Various engine and combustion parameters are estimated using parameter estimation toolbox from MATLAB and Simulink by applying least squared solver to minimize the error between measured and estimated variables. This model is validated against the virtual engine model developed in GT-power for Cummins 6.7L turbo diesel engine. To account the harmonization of the testing cycles to save engine development time globally, a world harmonized stationary cycle (WHSC) is used for the validation. Sub-systems are validated individually as well as in loop with a complete model for WHSC. Engine model validation showed promising accuracy of more than 88.4 percent in average for the desired parameters required for the NO_xprediction. NO_x estimation is accurate for the cycle except warm up and cool down phase. However, NO_xprediction during these phases is limited due to actual NO_xmeasured data for tuning the model for real time NO_xestimation. Results are summarized at the end to compare the trend of NO_xestimation from the developed combustion and emission model to show the accuracy of in-cylinder parameters and required for the NO_x estimation.

Стилі APA, Harvard, Vancouver, ISO та ін.

39

Lin, Kuo-Chun. "Applying Matsuoka Neuronal Oscillator in traffic light control of intersections : a thesis presented in partial fulfillment of the requirements of the degree of Master of Engineering in Mechatronics at Massey University, Auckland, New Zealand." 2009. http://hdl.handle.net/10179/1236.

Повний текст джерела

Анотація:

The quality of Machine Translation (MT) can often be poor due to it appearing incoherent and lacking in fluency. These problems consist of word ordering, awkward use of words and grammar, and translating text too literally. However we should not consider translations such as these failures until we have done our best to enhance their quality, or more simply, their fluency. In the same way various processes can be applied to touch up a photograph, various processes can also be applied to touch up a translation. This research outlines the improvement of MT quality through the application of Fluency Enhancement (FE), which is a process we have created that reforms and evaluates text to enhance its fluency. We have tested our FE process on our own MT system which operates on what we call the SAM fundamentals, which are as follows: Simplicity - to be simple in design in order to be portable across different languages pairs, Adaptability - to compensate for the evolution of language, and Multiplicity - to determine a final set of translations from as many candidate translations as possible. Based on our research, the SAM fundamentals are the key to developing a successful MT system, and are what have piloted the success of our FE process.

Стилі APA, Harvard, Vancouver, ISO та ін.

40

(11205843), Ahmed Mohammed Al Otaibi. "Polymer Nanocomposite-Based Wide Band Strain Sensor for 3D Force Measurement Using Piezoelectric and Piezoresistive Data Fusion." Thesis, 2021.

Знайти повний текст джерела

Анотація:

Polymer nanocomposites (PNC) have an excellent potential for in-situ strain sensing applications in static and dynamic loading scenarios. These PNCs have a polymer matrix of polyvinylidene fluoride (PVDF) with a conductive filler of multi-walled carbon nanotubes (MWCNT) and have both piezoelectric and piezoresistive characteristics. Generally, this composite would accurately measure either low-frequency dynamic strain using piezoresistive characteristic or high-frequency dynamic strains using piezoelectric characteristics of the MWCNT/PVDF film sensor. Thus, the frequency bands of the strain sensor are limited to either piezoresistive or piezoelectric ranges. In this study, a novel weighted fusion technique, called Piezoresistive/Piezoelectric Fusion (PPF), is proposed to combine both piezoresistive and piezoelectric characteristics to capture the wide frequency bands of strain measurements in real-time. This fuzzy logic (FL)-based method combines the salient features (i.e., piezoresistive and piezoelectric) of the nanocomposite sensor via reasonably accurate models to extend the frequency range over a wider band. The FL determines the weight of each signal based on the error between the estimated measurements and the actual measurements. These weights indicate the contribution of each signal to the final fused measurement. The Fuzzy Inference System (FIS) was developed using both optimization and data clustering techniques. In addition, a type-2 FIS was utilized to overcome the model’s uncertainty limitations. The developed PPF methods were verified with experimental data at different dynamic frequencies that were obtained from existing literature. The fused measurements of the MWCNT/PVDF were found to correlate very well with the actual strain, and a high degree of accuracy was achieved by the subtractive clustering PPF’s FISs algorithm.

3D force sensors have proven their effectiveness and relevance for robotics applications. They have also been used in medical and physical therapy applications such as surgical robots and Instrument Assisted Soft Tissue Manipulation (IASTM). The 3D force sensors have been utilized in robot-assisted surgeries and modern physical therapy devices to monitor the 3D forces for improved performances. The 3D force sensor performance and specifications depend on different design parameters, such as the structural configuration, placement of the sensing elements, and load criterion. In this work, different bioinspired structure configurations have been investigated and analyzed to obtain the optimal 3D force sensor configuration in terms of structural integrity, compactness, the safety factor, and strain sensitivity. A Finite Element Analysis (FEA) simulation was used for the analysis to minimize the time of the development cycle.

A tree branch design was used as the 3D force sensor’s elastic structure. The structure was made of aluminum with a laser-cutting fabrication process. The PVDF/MWCNT films contained piezoresistive and piezoelectric characteristics that allowed for static/low strain measurements and dynamic strain measurements, respectively. Two compositions with 0.1 wt.% and 2 wt.% PVDF/MWCNT sensing elements were selected for piezoelectric and piezoresistive strain measurements, respectively. These characteristic measurements were investigated under different vibration rates in a supported beam experiment. The 3D force sensor was tested under dynamic excitation in the Z-direction and the X-direction. A Direct Piezoresistive/Piezoelectric Fusion (DPPF) method was developed by fusing the piezoresistive and piezoelectric measurements at a given frequency that overcomes the limited frequency ranges of each of the strain sensor characteristics. The DPPF method is based on a fuzzy inference system (FIS) which is constructed and tuned using the subtractive clustering technique. Different nonlinear Hammerstein-Wiener (nlhw) models were used to estimate the actual strain from piezoresistive and piezoelectric measurements at the 3D force sensor. The DPPF method was tested and validated for different strain signal types using presumed Triangle and Square signal waves data. The DPPF has proven its effectiveness in fusing piezoresistive and piezoelectric measurements with different types of signals. In addition, an Extended Direct Piezoresistive/Piezoelectric Fusion (EPPF) is introduced to enhance the DPPF method and perform the fusion in a range of frequencies instead of a particular one. The DPPF and EPPF methods were implemented on the 3D force sensor data, and the developed fusion algorithms were tested on the proposed 3D force sensor experimental data. The simulation results show that the proposed fusion methods have been effective in achieving lower Root Mean Square Error (RMSE) than those obtained from the tuned nlhw models at different operating frequencies.

Стилі APA, Harvard, Vancouver, ISO та ін.

41

Granåsen, Magdalena. "Exploring C2 Capability and Effectiveness in Challenging Situations : Interorganizational Crisis Management, Military Operations and Cyber Defence." Licentiate thesis, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156151.

Повний текст джерела

Анотація:

Modern societies are affected by various threats and hazards, including natural disasters, cyber-attacks, extreme weather events and inter-state conflicts. Managing these challenging situations requires immediate actions, suspension of ordinary procedures, decision making under uncertainty and coordinated action. In other words, challenging situations put high demands on the command and control (C2) capability. To strengthen the capability of C2, it is vital to identify the prerequisites for effective coordination and direction within the domain of interest. This thesis explores C2 capability and effectiveness in three domains: interorganizational crisis management, military command and control, and cyber defence operations. The thesis aims to answer three research questions: (1) What constitutes C2 capability? (2) What constitutes C2 effectiveness? and (3) How can C2 effectiveness be assessed? The work was carried out as two case studies and one systematic literature review. The main contributions of the thesis are the identification of perspectives of C2 capability in challenging situations and an overview of approaches to C2 effectiveness assessment. Based on the results of the three studies, six recurring perspectives of capability in the domains studied were identified: interaction (collaboration), direction and coordination, relationships, situation awareness, resilience and preparedness. In the domains there are differences concerning which perspectives that are most emphasized in order obtain C2 capability. C2 effectiveness is defined as the extent to which a C2 system is successful in achieving its intended result. The thesis discusses the interconnectedness of performance and effectiveness measures, and concludes that there is not a united view on the difference between measures of effectiveness and measures of performance. Different approaches to effectiveness assessment were identified, where assessment may be conducted based on one specific issue, in relation to a defined goal for a C2 function or using a more exploratory approach.

In the printed version is the permanent link to this publication incorrect. The link is changecd in the online version.

Стилі APA, Harvard, Vancouver, ISO та ін.

42

Gregory, Unéné N. "Design of a lower extremity mechatronic system to assist physically impaired individuals achieve a standing position." 2014. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001344.

Повний текст джерела

Анотація:

M. Tech. Electrical Engineering.
The hypothesis states that a closed loop control system could be applied to a mechatronic system consisting of a mechanical device(s) to be fitted onto the user, and other relevant periphery mechanical devices, appropriately actuated to provide powered movement to assist the wheelchair-bound individual securely attain a standing position.The premise upon which the hypothesis was to be tested relates to the control system's ability to facilitate the upward movement proposed and its degree of stability when simulating the system, thus re-creating the anticipated functionality.

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Wu, Hongda. "Developing an integrated system for automated picking and sorting using an ABB flexpicker robot : a thesis presented in partial fulfillment of the requirements of the degree of Master of Engineering in Mechatronics at Massey University, Auckland, New Zealand." 2010. http://hdl.handle.net/10179/1684.

Повний текст джерела

Анотація:

Content on CD can be found with print thesis held at Turitea library, Palmerston North. Content: Chapter 8 Appendix 8.1. PLC Code 8.2. Mean-Shift Code 8.3. Webcam Interface HTML Code 8.4. PIC18F4520
In the rapid development of flexible automation and the broad application of computer technology, industrial monitor software has played an integral role in all kinds of industrial areas. It allows operators to monitor and control a plant in real-time with feedback from any number of processes. Traditionally industrial monitor software exhibits low efficiency, lack of reliability, non-reconfigurable and does not support multi-communication protocols, as is required for the exchange of data from outside of the factory. (Fan, 2006) Configuration software is basically type of the industrial automation and process monitor and control application. It supports Human Machine Interface (HMI), Supervisory Control and Data Acquisition (SCADA) system, realizes interlink between low level device and upper management network. Nowadays, with the advent of Configuration Software, engineers can readily construct field control systems with minimal developmental time and cost while allowing the combination of a plethora of user requests and control. The primary objective of this thesis is to develop a web base application with surveillance ability to realize remote control of an ABB IRB 340 Flexpicker robot through Siemens Programmable Logic Controller (PLC) system. The communication between the application and robot system is to be built using configuration software to link a number of third party devices through the inclusion of OLE for Process Control (OPC) techniques, graphical design editors, web navigators, and tag management. The thesis also introduces a vision system with trig-board design for object recognition and tracking.

Стилі APA, Harvard, Vancouver, ISO та ін.

44

(10725597), Omkar Mahesh Parkar. "Multi-Objective Optimization of Plug-in HEV Powertrain Using Modified Particle Swarm Optimization." Thesis, 2021.

Знайти повний текст джерела

Анотація:

Increase in the awareness environmental conservation is leading the automotive industry into the adaptation of alternatively fueled vehicles. Electric, Fuel-Cell as well as Hybrid-Electric vehicles focus on this research area with aim to efficiently utilize vehicle powertrain as the first step. Energy and Power Management System control strategies play vital role in improving efficiency of any hybrid propulsion system. However, these control strategies are sensitive to the dynamics of the powertrain components used in the given system. A kinematic mathematical model for Plug-in Hybrid Electric Vehicle (PHEV) has been developed in this study and is further optimized by determining optimal power management strategy for minimal fuel consumption as well as NOx emissions while executing a set drive cycle. A multi-objective optimization using weighted sum formulation is needed in order to observe the trade-off between the optimized objectives. Particle Swarm Optimization (PSO) algorithm has been used in this research, to determine the trade-off curve between fuel and NOx. In performing these optimizations, the control signal consisting of engine speed and reference battery SOC trajectory for a 2-hour cycle is used as the controllable decision parameter input directly from the optimizer. Each element of the control signal was split into 50 distinct points representing the full 2 hours, giving slightly less than 2.5 minutes per point, noting that the values used in the model are interpolated between the points for each time step. With the control signal consisting of 2 distinct signals, speed and SOC trajectory, as 50 element time variant signals, a multidimensional problem was formulated for the optimizer. Novel approaches to balance the optimizer exploration and convergence, as well as seeding techniques are suggested to solve the optimal control problem. The optimization of each involved individual runs at 5 different weight levels with the resulting cost populations being compiled together to visually represent with the help of Pareto front development. The obtained results of simulations and optimization are presented involving performances of individual components of the PHEV powertrain as well as the optimized PMS strategy to follow for given drive cycle. Observations of the trade-off is discussed in the case of Multi-Objective Optimizations.

Стилі APA, Harvard, Vancouver, ISO та ін.

45

(9976460), Xu Zhang. "Model-based co-design of sensing and control systems for turbo-charged, EGR-utilizing spark-ignited engines." Thesis, 2021.

Знайти повний текст джерела

Анотація:

Stoichiometric air-fuel ratio (AFR) and air/EGR flow control are essential control problems in today’s advanced spark-ignited (SI) engines to enable effective application of the three-way-catalyst (TWC) and generation of required torque. External exhaust gas recirculation (EGR) can be used in SI engines to help mitigate knock, reduce enrichment and improve efficiency[1 ]. However, the introduction of the EGR system increases the complexity of stoichiometric engine-out lambda and torque management, particularly for high BMEP commercial vehicle applications. This thesis develops advanced frameworks for sensing and control architecture designs to enable robust air handling system management, stoichiometric cylinder air-fuel ratio (AFR) control and three-way-catalyst emission control.

The first work in this thesis derives a physically-based, control-oriented model for turbocharged SI engines utilizing cooled EGR and flexible VVA systems. The model includes the impacts of modulation to any combination of 11 actuators, including the throttle valve, bypass valve, fuel injection rate, waste-gate, high-pressure (HP) EGR, low-pressure (LP) EGR, number of firing cylinders, intake and exhaust valve opening and closing timings. A new cylinder-out gas composition estimation method, based on the inputs’ information of cylinder charge flow, injected fuel amount, residual gas mass and intake gas compositions, is proposed in this model. This method can be implemented in the control-oriented model as a critical input for estimating the exhaust manifold gas compositions. A new flow-based turbine-out pressure modeling strategy is also proposed in this thesis as a necessary input to estimate the LP EGR flow rate. Incorporated with these two sub-models, the control-oriented model is capable to capture the dynamics of pressure, temperature and gas compositions in manifolds and the cylinder. Thirteen physical parameters, including intake, boost and exhaust manifolds’ pressures, temperatures, unburnt and burnt mass fractions as well as the turbocharger speed, are defined as state variables. The outputs such as flow rates and AFR are modeled as functions of selected states and inputs. The control-oriented model is validated with a high fidelity SI engine GT-Power model for different operating conditions. The novelty in this physical modeling work includes the development and incorporation of the cylinder-out gas composition estimation method and the turbine-out pressure model in the control-oriented model.

The second part of the work outlines a novel sensor selection and observer design algorithm for linear time-invariant systems with both process and measurement noise based on H2 optimization to optimize the tradeoff between the observer error and the number of required sensors. The optimization problem is relaxed to a sequence of convex optimization problems that minimize the cost function consisting of the H2 norm of the observer error and the weighted l1 norm of the observer gain. An LMI formulation allows for efficient solution via semi-definite programing. The approach is applied here, for the first time, to a turbo-charged spark-ignited (SI) engine using exhaust gas recirculation to determine the optimal sensor sets for real-time intake manifold burnt gas mass fraction estimation. Simulation with the candidate estimator embedded in a high fidelity engine GT-Power model demonstrates that the optimal sensor sets selected using this algorithm have the best H2 estimation performance. Sensor redundancy is also analyzed based on the algorithm results. This algorithm is applicable for any type of modern internal combustion engines to reduce system design time and experimental efforts typically required for selecting optimal sensor sets.

The third study develops a model-based sensor selection and controller design framework for robust control of air-fuel-ratio (AFR), air flow and EGR flow for turbocharged stoichiometric engines using low pressure EGR, waste-gate turbo-charging, intake throttling and variable valve timing. Model uncertainties, disturbances, transport delays, sensor and actuator characteristics are considered in this framework. Based on the required control performance and candidate sensor sets, the framework synthesizes an H1 feedback controller and evaluates the viability of the candidate sensor set through analysis of the structured

singular value μ of the closed-loop system in the frequency domain. The framework can also be used to understand if relaxing the controller performance requirements enables the use of a simpler (less costly) sensor set. The sensor selection and controller co-design approach is applied here, for the first time, to turbo-charged engines using exhaust gas circulation. High fidelity GT-Power simulations are used to validate the approach. The novelty of the work in this part can be summarized as follows: (1) A novel control strategy is proposed for the stoichiometric SI engines using low pressure EGR to simultaneously satisfy both the AFR and air/EGR-path control performance requirements; (2) A parametrical method to simultaneously select the sensors and design the controller is first proposed for the internal combustion engines.

In the fourth part of the work, a novel two-loop estimation and control strategy is proposed to reduce the emission of the three-way-catalyst (TWC). In the outer loop, an FOS estimator consisting of a TWC model and an extended Kalman-filter is used to estimate the current TWC fractional oxygen state (FOS) and a robust controller is used to control the TWC FOS by manipulating the desired engine λ. The outer loop estimator and controller are combined with an existing inner loop controller. The inner loop controller controls the engine λ based on the desired λ value and the control inaccuracies are considered and compensated by the outer loop robust controller. This control strategy achieves good emission reduction performance and has advantages over the constant λ control strategy and the conventional two-loop switch-type control strategy.

Стилі APA, Harvard, Vancouver, ISO та ін.

46

(10725198), Yi Yang. "Electromechanical Characterization of Organic Field-Effect Transistors with Generalized Solid-State and Fractional Drift-Diffusion Models." Thesis, 2021.

Знайти повний текст джерела

Анотація:

The miniaturization and thinning of wearable, soft robotics and medical devices are soon to require higher performance modeling as the physical flexibility causes direct impacts on the electrical characteristics of the circuit – changing its behavior. As a representative flexible electronic component, the organic field effect transistor (OFET) has attracted much attention in its manufacturing as well as applications. However, as the strain and stress effects are integrated into multiphysics modelers with deeper interactions, the computational complexity and accuracy of OFET modeling is resurfacing as a limiting bottleneck.

The dissertation was organized into three interrelated studies. In the first study, the Mass-Spring-Damper (MSD) model for an inverted staggered thin film transistor (TFT) was proposed to investigate the TFT’s internal stress/strain fields, and the strain effects on the overall characteristics of the TFT. A comparison study with the finite element analysis (FEA) model shows that the MSD model can reduce memory usage and raises the computational convergence speed for rendering the same results as the FEA. The second study developed the generalized solid-state model by incorporating the density of trap states in the band structure of organic semiconductors (OSCs). The introduction of trap states allows the generalized solid-state model to describe the electrical characteristics of both inorganic TFTs and organic field-effect transistors (OFETs). It is revealed through experimental verification that the generalized solid-state model can accurately characterize the bending induced electrical properties of an OFET in the linear and saturation regimes. The third study aims to model the transient and steady-state dynamics of an arbitrary organic semiconductor device under mechanical strain. In this study, the fractional drift-diffusion (Fr-DD) model and its computational scheme with high accuracy and high convergence rate were proposed. Based on simulation and experimental validation, the transconductance and output characteristics of a bendable OFET were found to be well determined by the Fr-DD model not only in the linear and saturation regimes, but also in the subthreshold regime.

Стилі APA, Harvard, Vancouver, ISO та ін.

47

Vaezi, Masoud. "Modeling and control of hydraulic wind power transfer systems." Thesis, 2014. http://hdl.handle.net/1805/6172.

Повний текст джерела

Анотація:

Indiana University-Purdue University Indianapolis (IUPUI)
Hydraulic wind power transfer systems deliver the captured energy by the blades to the generators differently. In the conventional systems this task is carried out by a gearbox or an intermediate medium. New generation of wind power systems transfer the captured energy by means of high-pressure hydraulic fluids. A hydraulic pump is connected to the blades shaft at a high distance from the ground, in nacelle, to pressurize a hydraulic flow down to ground level equipment through hoses. Multiple wind turbines can also pressurize a flow sending to a single hose toward the generator. The pressurized flow carries a large amount of energy which will be transferred to the mechanical energy by a hydraulic motor. Finally, a generator is connected to the hydraulic motor to generate electrical power. This hydraulic system runs under two main disturbances, wind speed fluctuations and load variations. Intermittent nature of the wind applies a fluctuating torque on the hydraulic pump shaft. Also, variations of the consumed electrical power by the grid cause a considerable load disturbance on the system. This thesis studies the hydraulic wind power transfer systems. To get a better understanding, a mathematical model of the system is developed and studied utilizing the governing equations for every single hydraulic component in the system. The mathematical model embodies nonlinearities which are inherited from the hydraulic components such as check valves, proportional valves, pressure relief valves, etc. An experimental prototype of the hydraulic wind power transfer systems is designed and implemented to study the dynamic behavior and operation of the system. The provided nonlinear mathematical model is then validated by experimental result from the prototype. Moreover, this thesis develops a control system for the hydraulic wind power transfer systems. To maintain a fixed frequency electrical voltage by the system, the generator should remain at a constant rotational speed. The fluctuating wind speed from the upstream, and the load variations from the downstream apply considerable disturbances on the system. A controller is designed and implemented to regulate the flow in the proportional valve and as a consequence the generator maintains its constant speed compensating for load and wind turbine disturbances. The control system is applied to the mathematical model as well as the experimental prototype by utilizing MATLAB/Simulink and dSPACE 1104 fast prototyping hardware and the results are compared.

Стилі APA, Harvard, Vancouver, ISO та ін.

48

(6331784), Ryan P. Jenkins. "An Analysis of a Pressure Compensated Control System of an Automotive Vane Pump." Thesis, 2019.

Знайти повний текст джерела

Анотація:

Pressure compensated vane pump systems are an attractive solution in many automotive applications to supply hydraulic power required for cooling, lubrication, and actuation of control elements such as transmission clutches. These systems feature variable displacement vane pumps which offer reductions in parasitic loads on the engine and in wasted hydraulic energy at high engine speeds when compared to traditional fixed displacement supply pumps. However, oscillations in a currently available pressure compensation system limits the achievable performance and therefore the application of this solution.

This dissertation presents the development and experimental validation of a lumped parameter model in MATLAB/Simulink of a current pressure compensated vane pump system for an automatic transmission oil supply application. An analysis of the performance of this system using the validated pump model and a developed black box control system model reveals that the low cost solenoid valve present in the control circuit to set the regulation pressure limits the achievable bandwidth to 1.84Hz and causes a significant time delay in the response. To address this limitation, as well as eliminate a non-minimum phase zero introduced by the case study’s control circuit architecture, an actively controlled electrohydraulic pressure compensation system is proposed. This proposed system is explored both experimentally and in simulation making use of the accuracy of the presented variable displacement vane pump model. Significant improvements in the achievable system performance are shown with both a simple PI control law (47% reduction in the pressure response time) and an advanced cascaded model following controller based on feedback linearization (58% reduction in the pressure response time). An analysis of these results reveals that implementing the proposed control system with a 5(L/min)/bar proportional valve with a 20Hz at ±100% (60Hz at ±50%) amplitude bandwidth and a PI control law is an economical path to achieving the best performance improvements for this automotive application.

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Bearden, Lukas R. "An Automated Grid-Based Robotic Alignment System for Pick and Place Applications." Thesis, 2013. http://hdl.handle.net/1805/4436.

Повний текст джерела

Анотація:

Indiana University-Purdue University Indianapolis (IUPUI)
This thesis proposes an automated grid-based alignment system utilizing lasers and an array of light-detecting photodiodes. The intent is to create an inexpensive and scalable alignment system for pick-and-place robotic systems. The system utilizes the transformation matrix, geometry, and trigonometry to determine the movements to align the robot with a grid-based array of photodiodes. The alignment system consists of a sending unit utilizing lasers, a receiving module consisting of photodiodes, a data acquisition unit, a computer-based control system, and the robot being aligned. The control system computes the robot movements needed to position the lasers based on the laser positions detected by the photodiodes. A transformation matrix converts movements from the coordinate system of the grid formed by the photodiodes to the coordinate system of the robot. The photodiode grid can detect a single laser spot and move it to any part of the grid, or it can detect up to four laser spots and use their relative positions to determine rotational misalignment of the robot. Testing the alignment consists of detecting the position of a single laser at individual points in a distinct pattern on the grid array of photodiodes, and running the entire alignment process multiple times starting with different misalignment cases. The first test provides a measure of the position detection accuracy of the system, while the second test demonstrates the alignment accuracy and repeatability of the system. The system detects the position of a single laser or multiple lasers by using a method similar to a center-of-gravity calculation. The intensity of each photodiode is multiplied by the X-position of that photodiode. The summed result from each photodiode intensity and position product is divided by the summed value of all of the photodiode intensities to get the X-position of the laser. The same thing is done with the Y-values to get the Y-position of the laser. Results show that with this method the system can read a single laser position value with a resolution of 0.1mm, and with a maximum X-error of 2.9mm and Y-error of 2.0mm. It takes approximately 1.5 seconds to process the reading. The alignment procedure calculates the initial misalignment between the robot and the grid of photodiodes by moving the robot to two distinct points along the robot’s X-axis so that only one laser is over the grid. Using these two detected points, a movement trajectory is generated to move that laser to the X = 0, Y = 0 position on the grid. In the process, this moves the other three lasers over the grid, allowing the system to detect the positions of four lasers and uses the positions to determine the rotational and translational offset needed to align the lasers to the grid of photodiodes. This step is run in a feedback loop to update the adjustment until it is within a permissible error value. The desired result for the complete alignment is a robot manipulator positioning within ±0.5mm along the X and Y-axes. The system shows a maximum error of 0.2mm in the X-direction and 0.5mm in the Y-direction with a run-time of approximately 4 to 5 minutes per alignment. If the permissible error value of the final alignment is tripled the alignment time goes down to 1 to 1.5 minutes and the maximum error goes up to 1.4mm in both the X and Y-directions. The run time of the alignment decreases because the system runs fewer alignment iterations.

Стилі APA, Harvard, Vancouver, ISO та ін.

Дисертації з теми "Mechatronics engineering in defence systems"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями