Dissertations / Theses on the topic 'Aircraft Thermal Management Systems'
To see the other types of publications on this topic, follow the link: Aircraft Thermal Management Systems.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Aircraft Thermal Management Systems.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Reed, William Cody. "Comparison of Heat Exchanger Designs for Aircraft Thermal Management Systems." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/75142.
Full textAbstract:
Thermal management has become a major concern in the design of current and future more and all electric aircraft (M/AEA). With ever increasing numbers of on-board heat sources, higher heat loads, limited and even decreasing numbers of heat sinks, integration of advanced intelligence, surveillance and reconnaissance (ISR) and directed energy weapons, requirements for survivability, the use of composite materials, etc., existing thermal management systems and their components have been pushed to the limit. To address this issue, more efficient methods of thermal management must be implemented to ensure that these new M/AEA aircraft do not overheat and prematurely abort their missions. Crucial to this effort is the need to consider advanced heat exchanger concepts, comparing their designs and performance with those of the conventional compact exchangers currently used on-board aircraft thermal management systems. As a step in this direction, the work presented in this thesis identifies two promising advanced heat exchanger concepts, namely, microchannel and phase change heat exchangers. Detailed conceptual design and performance models for these as well as for a conventional plate-fin compact heat exchanger are developed and their design and performance optimized relative to the criterion of minimum dry weight. Results for these optimizations are presented, comparisons made, conclusions drawn, and recommendations made for future research. These results and comparisons show potential performance benefits for aircraft thermal management incorporating microchannel and phase change heat exchangers.Master of Science
2
Tipton, Austin L. "Simulation, Experimentation, Control and Management of a Novel Fuel Thermal System." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1578320719632833.
Full text
3
Maser, Adam Charles. "Optimal allocation of thermodynamic irreversibility for the integrated design of propulsion and thermal management systems." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45913.
Full textAbstract:
More electric aircraft systems, high power avionics, and a reduction in heat sink capacity have placed a larger emphasis on correctly satisfying aircraft thermal management requirements during conceptual design. Thermal management systems must be capable of dealing with these rising heat loads, while simultaneously meeting mission performance. Since all subsystem power and cooling requirements are ultimately traced back to the engine, the growing interactions between the propulsion and thermal management systems are becoming more significant. As a result, it is necessary to consider their integrated performance during the conceptual design of the aircraft gas turbine engine cycle to ensure that thermal requirements are met. This can be accomplished by using thermodynamic modeling and simulation to investigate the subsystem interactions while conducting the necessary design trades to establish the engine cycle. As the foundation for this research, a parsimonious, transparent thermodynamic model of propulsion and thermal management systems performance was created with a focus on capturing the physics that have the largest impact on propulsion design choices. A key aspect of this approach is the incorporation of physics-based formulations involving the concurrent usage of the first and second laws of thermodynamics to achieve a clearer view of the component-level losses. This is facilitated by the direct prediction of the exergy destruction distribution throughout the integrated system and the resulting quantification of available work losses over the time history of the mission. The characterization of the thermodynamic irreversibility distribution helps give the designer an absolute and consistent view of the tradeoffs associated with the design of the system. Consequently, this leads directly to the question of the optimal allocation of irreversibility across each of the components. An irreversibility allocation approach based on the economic concept of resource allocation is demonstrated for a canonical propulsion and thermal management systems architecture. By posing the problem in economic terms, exergy destruction is treated as a true common currency to barter for improved efficiency, cost, and performance. This then enables the propulsion systems designer to better fulfill system-level requirements and to create a system more robust to future requirements.
4
Thomas, Kevin P. "System architecture for real time power management." Thesis, University of Bristol, 1996. http://hdl.handle.net/1983/b4d196a1-d1f8-4141-b6e3-a32eb4f2073f.
Full textAbstract:
A major characteristic of aircraft evolution is the rapid growth in the electrical and electronic content of each subsequenat ircraft generation.T he dominant technology used in an aircraft electrical power distribution network to switch power and to protect the aircraft wiring from hazardous electrical faults is the electro-mechanical relay switch and the electro-thermal circuit breaker. Despite the maturity of these devices they do however suffer from a number of problems relating to reliability, accuracy, and limited operational lifetime. The design, fabrication and testing of a novel Solid State Power Controller (SSPC) is described. The design uses power MOSFET's to provide both the power switching operation of a relay, and the power interruption capability of a circuit breaker. The majority of the control functions required by this device are performed digitally by virtue of a real time program executed on an embedded microcontroller. A number of methods are derived for characterising existing I2t wire protection trip response curves. Reproduction of a true 1 2t trip response in real time using iterative computational methods is described. An examination of the semiconductor thermal characteristics was undertaken. The methods adopted for extracting the power semiconductor thermal response involved direct measurement using infrared thermal imaging techniques and simulation using a computer based modelling tool. Knowledge of the semiconductor die temperature is of vital importance in the context of the overall protection strategy. A finite difference calculation performed in real time has been demonstrated as a viable method to predict the operational temperature of the MOSFET power switching devices used in the design
5
Jones, Andy. "Component-led integrative optimisation methodology for avionic thermal management." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/24785.
Full textAbstract:
The modern military aircraft can be defined as a System of Systems (SoS); several distinct systems operating simultaneously across boundary interfaces. As the on-board subsystems have become more complex and diverse, the development process has become more isolated. When considering thermal management of distributed heat loads, the aircraft has become a collection of individually optimised components and subsystems, rather than the implementation of a single system to perform a given task. Avionic thermal management is quickly becoming a limiting factor of aircraft performance, reliability and effectiveness. The challenge of avionic thermal management is growing with the increasing complexity and power density of avionic packages. The aircraft relies on a heat rejection growth capacity to accommodate the additional through-life avionic heat loads. Growth capacity is defined as an allowable thermal loading growth designed into the system by the underutilisation of spatial and cooling supply at aircraft introduction; however, this is a limited resource and aircraft subsystem cooling capability is reaching a critical point. The depleted growth capacity coupled with increased avionic power demands has led to component thermal failure. However, due to the poor resolution of existing data acquisition, experimental facilities or thermodynamic modeling, the exact inflight-operating conditions remain relatively unknown. The knowledge gap identified in this work is the lack of definitive methodology to generate high fidelity data of in-flight thermal conditions of fast-jet subsystems and provide evidence towards effective future thermal management technologies. It is shown that, through the development of a new methodology, the knowledge gap can be reduced and as an output of this approach the unknown system behaviour can be defined. A multidisciplinary approach to the replication, analysis and optimisation of a fast-jet TMS is detailed. The development of a new Ground Test Facility (GTF) allows previously unidentified system thermal behaviour to be evaluated at component, subsystem and system level. The development of new data to characterise current thermal performance of a fast jet TMS allows recommendations of several new technologies to be implemented through a component led integrative system optimisation. This approach is to consider the TMS as a single system to achieve a single goal of component thermal management. Three technologies are implemented to optimise avionic conditions through the minimisation of bleed air consumption, improve avionic reliability through increased avionic component isothermalisation and increase growth capacity through improved avionic heat exchanger fin utilisation. These component level technologies improved system level performance. A reduction in TMS bleed air consumption from 1225kg to 510kg was found to complete a typical flight profile. A peak predicted aircraft specific fuel consumption saving of 1.23% is seen at a cruise flight condition because of this approach to avionic thermal management.
6
Lammers, Zachary A. "Thermal Management of Electromechanical Actuation System for Aircraft Primary Flight Control Surfaces." University of Dayton / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1399021324.
Full text
7
Allen, Christopher T. "Global Optimization of an Aircraft Thermal Management System through Use of a Genetic Algorithm." Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1220969610.
Full text
8
Payne, Nathaniel M. "Development of a Combined Thermal Management and Power Generation System using a Multi-Mode Rankine Cycle." Wright State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1622657194320193.
Full text
9
Butt, Nathaniel J. "Development and Thermal Management of a Dynamically Efficient, Transient High Energy Pulse System Model." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1527602141695356.
Full text
10
Khanna, Yash. "Conceptual design and development of thermal management system for hybrid electric aircraft engine. : A study to develop a physical model and investigate the use of Mobil Jet Oil II as coolant for aircraft electrical propulsion under different scenarios and time horizons." Thesis, Mälardalens högskola, Framtidens energi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-46612.
Full textAbstract:
The ever-increasing levels of greenhouse gas emissions has led to the scientific community starting to explore the viability of electrical aircraft system, with the most prominent research and product development for hybrid electric system, which forms the transition phase from combustion to fully electric aircrafts. The primary objective of this thesis is to find solutions towards thermal management of the electrical components of a hybrid electric aircraft propulsion system, which generate a significant amount of heat while operating at heavy load conditions required to propel an aircraft. In view of these objectives a micro channel cold plate liquid cooling system, has been dynamically modelled using a combination of lumped parameter and thermal resistance methods of heat transfer analysis. The study investigates the prospects of using Mobil Jet Oil II, typically used as an aircraft lubricant as a coolant for the thermal management system. The primary components of this model are lithium ion battery, DC-AC inverter, permanent magnet motor, cross flow finned micro channel heat exchanger, centrifugal pump and ducts. The electrical components have been dimensioned according to energy storage and load requirements considering their efficiencies and gravimetric power/energy. The system has been simulated and analyzed under different scenarios considering the coolant inlet temperature, air temperature across the heat exchanger and on two-time horizons. Analysis has been done to study the dynamic trends of the component temperature and the coolant at different stages of the system. The scope of the study includes an evaluation of the added weight of the thermal management system under different time horizons and their comparison with results from a reference study. From the simulation results it can be concluded that Mobil Jet Oil II is a promising option as a coolant and therefore its use as a common fluid for gas turbine lubrication and as coolant, will benefit the aircraft as now no extra coolant reservoir is required, allowing reduction in weight carried by the aircraft.
11
Fleming, Andrew J. "Aircraft Thermal Management Using Loop Heat Pipes." Wright State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=wright1238086423.
Full text
12
Nuzum, Sean Robert. "Aircraft Thermal Management using Liquefied Natural Gas." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1462460693.
Full text
13
Donovan, Adam. "Vehicle Level Transient Aircraft Thermal Management Modeling and Simulation." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1472236965.
Full text
14
Sermeno, Mena Salvador. "Vehicle thermal management control systems." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0052.
Full textAbstract:
Les systèmes de refroidissement des véhicules continuent à se développer et devenir de plus en plus complexes. Ceci introduit des nouveaux problèmes dus aux interactions des composants et les perturbations du système. Avec la montée des prix des carburants; les développeurs et les compagnies cherchent à améliorer la consommation en respectant les normes d’émission. Une partie de l’énergie produite par le moteur est utilisé par les composants du circuit de refroidissement. L’utilisation d’auxiliaires électriques est une manière de réduire ces pertes parasites, mais ce n’est pas la seule solution. Des études récents proposent que un control plus adaptes des composants peux réduire la consommation de carburant. Actuellement, le groupe Volvo en essayant d’améliorer la performance du système de refroidissement des camions a installe des nouveaux composants pour la gestion thermique du moteur. Néanmoins, des problèmes ont été identifie lors d’essais véhicule. Une meilleure compréhension du système et de l’implémentation de composants est nécessaire pour limiter les effets non voulus. Le système de refroidissement d’un poids lourd a été étudié grâce à l’outil Bond Graph. Puis des nouvelles stratégies de control sont introduites : commande prédictive, commande par platitude, commande sans model et commande avec model réduit. Ces méthodes ont été implémentées dans une plateforme de simulation sur Matlab/Simulink. Les gains de consommation obtenue à partir de simulations sont entre 0.5 et 0.9%. Une analyse structurelle de l’architecture actuelle est présentée. D’après les conclusions de cette analyse, des propositions pour la modification de l’architecture du circuit sont évaluésThe increasing complexity of engine cooling systems results in added interactions and disturbances to the performance. Besides, non-propulsion loads (fan, water pump…) draw a significant percentage of the engine’s power thus lowering the vehicle’s fuel efficiency. Recent studies have shown that by controlling components the efficiency can be improved by adjusting fan speed according to cooling needs, coolant flow, and oil flow. Currently, the Volvo group in order to optimize the performance of their truck’s cooling systems had installed new thermal management components. However, problems were found while testing control strategies and a better understanding of the interaction between components is required to prevent this from happening again. In this work, the bond graph approach has been applied for the study of the cooling system of a Heavy duty vehicle and has enabled subsystem interactions to be identified. Based on a simplified model issued from the bond graph, several control strategies have been built. These controllers are based on different control approaches: model predictive control, flatness control, model free control and model free control with reduced order model. These controllers were implemented in a simulation platform in the Matlab/Simulink environment. Results of the implementation of the new advanced control strategies are given. Fuel economy gains ranged between 0.5 and 0.9 %. A structural analysis of the current architecture is also proposed aiming at the optimization of the system. Given the insights from the analysis, an assessment of new concepts for the cooling system architecture is proposed
15
McFarlane, Alexander. "Biofilm development and management in aircraft fuel systems." Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/17655/.
Full text
16
Coşkun, Ayşe Kıvılcım. "Efficient thermal management for multiprocessor systems." Diss., [La Jolla] : University of California, San Diego, 2009. http://wwwlib.umi.com/cr/ucsd/fullcit?p3372516.
Full textAbstract:
Thesis (Ph. D.)--University of California, San Diego, 2009.Title from first page of PDF file (viewed October 13, 2009). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 109-114).
17
Gibbons, Blake. "Safety Management Systems (SMS) for aircraft manufacturers and maintainers?" Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/9213.
Full textAbstract:
There is much dialogue in the global aviation industry about Safety Management Systems (SMS) and how it should be integrated across all domains of the industry including aircraft design, production, flight operations, overhaul and maintenance, suppliers, service providers, airports, and so forth (Johnson, 2012).
Regulators have made significant progress in recent years to implement ICAO’s SMS into airlines, albeit as a required or recommended practice. More recently the regulators are seeking to implement SMS into the aircraft manufacturing and aircraft maintenance domains.
This research reviewed regulatory publications from multiple countries to assess the technical makeup of SMS, and understand what regulators are requiring, or recommending, and when. It was found that global regulators accept the ICAO published definition of SMS, but different regulators have varying approaches regarding implementation. However, they are consistent in initially targeting airlines for SMS implementation. SMS comments range from “The best thing since sliced bread” to “Worst thing since the creation of the FAA; I don’t need anyone telling me what’s safe when I already know it; waste of time and money”.
This investigation experimented with field tests to connect the engineering, production and airline domains into one ICAO SMS model. Results indicate that because the different domains are risk-specific, the application of one safety risk management model to all domains is not viable. The SMS model applies to airlines because airlines’ primary risk is about operational safety. Aircraft production and maintenance is about production risk – therefore the risk model must be centric to process risk. Field test 3 tailored the ICAO SMS risk architecture to assess and mitigate process risk as applicable to the aircraft manufacturing and maintenance. Although the SMS architecture was usable, the content and focus was significantly adjusted to be production process-risk centric, to the point where the term “SMS’ was deemed out of place. The resulting model was therefore named Production Risk Management System (PRMS).
Following the emergence of PRMS from field tests, this investigation reviewed industry, research and regulatory arguments for and against SMS in the airline industry, and correlated those arguments with the benefits and non-benefits of PRMS for the manufacturing and aircraft maintenance domains.
The researcher advocates PRMS as a viable model that meets ICAO SMS-like architecture for aircraft production and maintenance. Methods were identified for developing and implementing PRMS, and for evaluating its ROI. If and when “SMS” is truly mandated in these domains, the researcher proposes PRMS as a viable model that should be considered. Furthermore, the researcher proposes that PRMS can be an effective production risk management system that can enhance the organization’s existing QMS, regardless of “SMS” regulations.
18
Demus, Justin Cole. "Prognostic Health Management Systems for More Electric Aircraft Applications." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1631047006902809.
Full text
19
Kreinar, David J. "Energy Management Techniques for Hybrid Electric Unmanned Aircraft Systems." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton159640308960136.
Full text
20
The'berge, Marc W. "Three case studies of management information systems." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA238310.
Full textAbstract:
Thesis (M.S. in Information Systems)--Naval Postgraduate School, September 1990.Thesis Advisor(s): Haga, William J. Second Reader: Zviran, Moshe. "September 1990." Description based on title screen as viewed on December 21, 2009. DTIC Identifier(s): Management Information Systems, Naval Operations, Data Bases, Instructional Materials, Decision Aids, Aviation Accidents, Antisubmarine Warfare, Naval Training, Local Area Networks, Theses. Author(s) subject terms: Case Studies, Database Management Systems, Local Area Networks, Decision Support. Includes bibliographical references. Also available in print.
21
Liu, Chih-Chun. "Dynamic thermal management in chip multiprocessor systems." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2913.
Full text
22
Desai, Anand Hasmukh. "Thermal management of small scale electronic systems." Diss., Online access via UMI:, 2006.
Find full text
23
Hamedi, Mohammadreza. "Advanced thermal management of diesel aftertreatment systems." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/7059/.
Full textAbstract:
State-of-the-art diesel exhaust gas aftertreatment systems have proved to substantially decrease vehicles’ emissions. However, their effectiveness depends on the temperature of the exhaust gas and catalysts to activate the emissions’ conversion reactions. In this research study, different strategies for thermal management of diesel aftertreatment systems were investigated to reduce vehicles’ emissions. A thermal energy storage (TES) system was developed and implemented for a light-duty diesel aftertreatment system. In this approach, the extra thermal energy of the exhaust gas during engine’s high-load conditions can be stored and reused when required, in order to maintain the emissions’ conversion reactions during a driving cycle. The results indicated that by increasing the thermal conductivity of the thermal energy storage medium and the catalyst’s substrate, the TES system can reduce the vehicle’s cumulative CO and THC emissions by 91.7% and 41.2% respectively. Active heating of the aftertreatment system was studied to provide the catalysts with the required thermal energy, in order to shorten the catalyst’s light-off period and also prevent the catalyst from light-out during a driving cycle. A pulsating electrical catalyst heating strategy and a combined electrical heating and fuel post-injection approach were developed to increase the heating efficiency while minimizing the vehicle’s emissions.
24
Lawee, Ian P. (Ian Philip). "Reducing development cycle time for aircraft electrical wiring systems." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/11530.
Full textAbstract:
Thesis (M.S.)--Massachusetts Institute of Technology, Sloan School of Management, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering, 1995.Includes bibliographical references (p. 93-94).
by Ian P. Lawee.
M.S.
25
Santamaría, Barnadas Eduard. "Formal mission specification and execution mechanisms for unmanned aircraft systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2010. http://hdl.handle.net/10803/6020.
Full textAbstract:
Unmanned Aircraft Systems (UAS) are rapidly gaining attention due to the increasing potential of their applications in the civil domain. UAS can provide great value performing environmental applications, during emergency situations, as monitoring and surveillance tools, and operating as communication relays among other uses. In general, they are specially well suited for the so-called D-cube operations (Dirty, Dull or Dangerous).Most current commercial solutions, if not remotely piloted, rely on waypoint based flight control systems for their navigation and are unable to coordinate UAS flight with payload operation. Therefore, automation capabilities and the ability for the system to operate in an autonomous manner are very limited. Some motivators that turn autonomy into an important requirement include limited bandwidth, limits on long-term attention spans of human operators, faster access to sensed data, which also results in better reaction times, as well as benefits derived from reducing operators workload and training requirements.
Other important requirements we believe are key to the success of UAS in the civil domain are reconfigurability and cost-effectiveness. As a result, an affordable platform should be able to operate in different application scenarios with reduced human intervention.
To increase capabilities of UAS and satisfy the aforementioned requirements, we propose adding flight plan and mission management layers on top of a commercial off-the-shelf flight control system. By doing so, a high level of autonomy can be achieved while taking advantage of available technologies and avoiding huge investments. Reconfiguration is made possible by separating flight and mission execution from its specification.
The flight and mission management components presented in this thesis integrate into a wider hardware/software architecture being developed by the ICARUS research group.
This architecture follows a service oriented approach where UAS subsystems are connected together through a common networking infrastructure. Components can be added and removed from the network in order to adapt the system to the target mission.
The first contribution of this thesis consists, then, in a flight specification language that enables the description of the flight plan in terms of legs. Legs provide a higher level of abstraction compared to plain waypoints since they not only specify a destination but also the trajectory that should be followed to reach it. This leg concept is extended with additional constructs that enable specification of alternative routes, repetition and generation of complex trajectories from a reduced number of parameters.
A Flight Plan Manager (FPM) service has been developed that is responsible for the execution of the flight plan. Since the underlying flight control system is still waypoint based, additional intermediate waypoints are automatically generated to adjust the flight to the desired trajectory.
In order to coordinate UAS flight and payload operation a Mission Manager (MMa) service has also been developed. The MMa is able to adapt payload operation according to the current flight phase, but it can also act on the FPM and make modifications on the flight plan for a better adaption to the mission needs. To specify UAS behavior, instead of designing a new language, we propose using an in-development standard for the specification of state machines called State Chart XML.
Finally, validation of the proposed specification and execution elements is carried out with two example missions executed in a simulation environment. The first mission mimics the procedures required for inspecting navigation aids and shows the UAS performance in a complex flight scenario. In this mission only the FPM is involved. The second example combines operation of the FPM with the MMa. In this case the mission consists in the detection of hotspots on a given area after a hypothetical wildfire. This second simulation shows how the MMa is able to modify the flight plan in order to adapt the trajectory to the mission needs. In particular, an eight pattern is flown over each of the dynamically detected potential hot spots.
26
Lin, Jiang. "Thermal modeling and management of DRAM memory systems." [Ames, Iowa : Iowa State University], 2008.
Find full text
27
Bradley, Thomas Heenan. "Modeling, design and energy management of fuel cell systems for aircraft." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26592.
Full textAbstract:
Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Parekh, David; Committee Member: Fuller, Thomas; Committee Member: Joshi, Yogendra; Committee Member: Mavris, Dimitri; Committee Member: Wepfer, William. Part of the SMARTech Electronic Thesis and Dissertation Collection.
28
Salah, Mohammad Hasan. "Nonlinear control strategies for advanced vehicle thermal management systems." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1202409346/.
Full text
29
McMillin, Timothy Walter. "Thermal management solutions for low volume complex electronic systems." College Park, Md.: University of Maryland, 2007. http://hdl.handle.net/1903/7368.
Full textAbstract:
Thesis (M.S.) -- University of Maryland, College Park, 2007.Thesis research directed by: Dept. of Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
30
Herrera, Jason (Jason Richard). "Evaluation of control systems for automated aircraft wing manufacturing." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82484.
Full textAbstract:
Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics; in conjunction with the Leaders for Global Operations Program at MIT, 2013.This electronic version was submitted and approved by the author's academic department as part of an electronic thesis pilot project. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from department-submitted PDF version of thesis
Includes bibliographical references (p. 62-64).
The Boeing Company is looking to bring aircraft manufacturing technology into the 21st century. As part of this process, several projects have been started to develop the technologies required to achieve Boeing's vision for the future of aircraft manufacturing. To date, much of this work has focused on hardware, including robotic and other automation technologies. However, in order to use this hardware, a significant effort must also be made in the area of factory control and coordination. This thesis advances knowledge in this area by evaluating the suitability of different control system approaches for aircraft wing box assembly. First, general classes of control systems are discussed and several criteria are proposed for evaluating their performance in an aircraft manufacturing environment. The current wing box assembly process is then examined in order to develop simplified but representative task networks to which various algorithms can be applied. The Tercio algorithm, developed at MIT, is used to generate schedules for several problem structures of interest in order to characterize the algorithm's performance in this context. The Tercio algorithm is then benchmarked against the Aurora scheduling tool, showing that Tercio can generate more efficient schedules than Aurora, but at the cost of increased computation time. Next, management considerations with respect to product design, manufacturing technology development, and implementation associated with advanced manufacturing technologies are discussed. Finally, recommendations are provided for how Boeing can accelerate the development of useful and practical advanced, automated manufacturing systems.
by Jason Herrera.
S.M.
M.B.A.
31
Kuroda, Scott H. "Distribution of Conflict Detection of Aircraft for Next Generation Flight Management Systems." DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1043.
Full textAbstract:
As the number of aircraft is expected to triple in the coming decades, the manual process used to safely route aircraft while in flight will become insufficient. There already exist work to algorithmically detect safe and unsafe routes between aircraft. This thesis extends that system such that the computation is distributed across multiple machines. In addition it also supports the detection of an unsafe route as it is actively modified by a third party. Furthermore, the system supports providing safe or unsafe route notification to multiple interested clients.
32
Bhatia, Padampat Chander. "Thermal Analysis of Lithium-Ion Battery Packs and Thermal Management Solutions." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1371144911.
Full text
33
Smarra, Devin. "Thermal Management and Packaging Techniques for High Performance Electrical Systems." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1591122977788952.
Full text
34
Kallinen, Valtteri A. "Collision risk modelling for unmanned aircraft separation and traffic management." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/232516/1/Valtteri_Kallinen_Thesis.pdf.
Full textAbstract:
This thesis develops models and procedures for designing safe airspace for Unmanned Aerial Vehicles (UAVs). Mid-air collision risk models with foundations in manned aviation are extended and adapted to develop separation standards for UAVs whilst addressing the unique differences from traditional manned aviation. Airspace design is also investigated using mathematical optimisation which maximises traffic throughput to make high-density operations viable, whilst still maintaining a given target level of safety.
35
Pienaar, Leanne Jane. "Probabilistic conflict detection for commercial aircraft near airports." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97033.
Full textAbstract:
Thesis (MEng)--Stellenbosch University, 2015.ENGLISH ABSTRACT: Increasing air traffic and urbanisation has led to a cluttered airspace, particularly near airports, where both complex terrain and multiple moving obstacles are frequent. Accurately and efficiently predicting violations in safe separation criteria for commercial aircraft, a process called conflict detection, is therefore crucial in assessing risk associated with threats of collision. Existing avoidance systems in operation such as TCAS, EGPWS and ATC exhibit shortcomings, leaving room for uncertainty and possible conflict scenarios. A single on-board system capable of minimising errors in prediction would inform conflict resolution decisions more accurately as well as support the notion of free flight, an objective of next-generation air traffic management systems. This thesis investigates the viability of a modern algorithm, probability flow, as a method of probabilistic conflict detection for commercial aircraft in airport environments. Simulation results for realistic flight scenarios are presented in comparison with a ground-truth result obtained through Monte Carlo simulation. Observations are made regarding the suitability of probability flow for real-world application. It is found that probability flow is capable of calculating a tight upper bound to the probability of conflict quickly and accurately for most conflict scenarios. However, unreasonably large overestimates on the probability of conflict are obtained when flying parallel to an obstacle conflict region. This problem could lead to a high frequency of false alerts, particularly in aborted landing scenarios and at airports operating parallel runways. It is therefore advised that further research be conducted to resolve this problem before probability flow can be reliably implemented in an airport environment.
AFRIKAANSE OPSOMMING: Toenemende lugverkeer en verstedeliking het gelei tot ‘n deurmekaar lugruim, veral naby lughawens, waar beide komplekse terrein en verskeie bewegende struikelblokke gereeld voorkom. Akkuraat en doeltreffende voorspelling van oortredings in veilige skeidingskriteria vir kommersiële vliegtuie, naamlik konflik opsporing, is dus van kardinale belang in die beoordeling van die risiko wat verband hou met dreigemente van ‘n botsing. Bestaande vermyding stelsels in werking soos TCAS, EGPWS en ATC toon tekortkominge, wat ruimte laat vir onsekerheid en moontlike konflik scenario’s. ‘n Enkele aanboordstelsel, wat in staat is om foute in voorspelling te verminder, sou konflikresolusie besluite meer akkuraat in kennis stel, asook om die idee van vrye vlug te ondersteun, ‘n doelwit van toekomstige lugverkeer beheerstelsels. Hierdie tesis ondersoek die lewensvatbaarheid van ‘n moderne algoritme, waarskynlikheidsvloei, as ‘n metode van probabilistiese konflik opsporing vir kommersiële vliegtuie in die lughawens omgewing. Simulasie resultate vir realistiese vlug scenario’s word aangebied in vergelyking met ‘n grond-waarheid resultaat wat verkry word deur middel van Monte Carlo simulasie. Waarnemings word gemaak ten opsigte van die geskiktheid van waarskynlikheidsvloei vir die werklikheid. Dit is bevind dat waarskynlikheidsvloei in staat is om die berekening van ‘n stywe bogrens tot die waarskynlikheid van konflik vinnig en akkuraat te bepaal vir die meeste konflik scenario’s. Tog is daar ‘n onredelike groot oorskatting op die waarskynlikheid van konflik wat verkry word wanneer ‘n vliegtuig parallel met ‘n hindernis konflik streek vlieg. Hierdie probleem kan lei tot ‘n hoë frekwensie van valse waarskuwings, veral in mislukte landing scenario’s en by lughawens wat van parallel aanloopbane gebruik maak. Dit word dus aanbeveel dat verdere navorsing gedoen word om die probleem op te los voordat waarskynlikheidsvloei betroubaar in ’n lughawe omgewing geïmplementeer word.
36
Lusk, Parker Chase. "Vision-Based Emergency Landing of Small Unmanned Aircraft Systems." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7029.
Full textAbstract:
Emergency landing is a critical safety mechanism for aerial vehicles. Commercial aircraft have triply-redundant systems that greatly increase the probability that the pilot will be able to land the aircraft at a designated airfield in the event of an emergency. In general aviation, the chances of always reaching a designated airfield are lower, but the successful pilot might use landmarks and other visual information to safely land in unprepared locations. For small unmanned aircraft systems (sUAS), triply- or even doubly-redundant systems are unlikely due to size, weight, and power constraints. Additionally, there is a growing demand for beyond visual line of sight (BVLOS) operations, where an sUAS operator would be unable to guide the vehicle safely to the ground. This thesis presents a machine vision-based approach to emergency landing for small unmanned aircraft systems. In the event of an emergency, the vehicle uses a pre-compiled database of potential landing sites to select the most accessible location to land based on vehicle health. Because it is impossible to know the current state of any ground environment, a camera is used for real-time visual feedback. Using the recently developed Recursive-RANSAC algorithm, an arbitrary number of moving ground obstacles can be visually detected and tracked. If obstacles are present in the selected ditch site, the emergency landing system chooses a new ditch site to mitigate risk. This system is called Safe2Ditch.
37
Wang, Yong. "Microfuidic technology for integrated thermal management micromachined synthetic jet /." Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180443/unrestricted/wang%5fyong%5f200312%5fphd.pdf.
Full text
38
Vakil, Sanjay S. (Sanjay Sridhar). "Analysis of complexity evolution management and human performance issues in commercial aircraft automation systems." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/9172.
Full textAbstract:
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2000.Includes bibliographical references (p. 181-187).
Autoflight systems in the current generation of aircraft have been implicated in several recent incidents and accidents. A contributory aspect to these incidents may be the manner in which aircraft transition between differing behaviours or "modes." The current state of aircraft automation was investigated and the incremental development of the autoflight system was tracked through a set of aircraft to gain insight into how these systems developed. This process appears to have resulted in a system without a consistent global representation. In order to evaluate and examine autoflight systems, a "Hybrid Automation Representation" was developed. This representation was used to examine several specific problems known to exist in aircraft systems. Cyclomatic complexity is an analysis tool from computer science which counts the number of linearly independent paths through a program graph. This approach was extended to examine autoflight mode transitions modelled with the Hybrid Automation Representation. A survey was conducted of pilots to identify those autoflight mode transitions which airline pilots find difficult. The transitions identified in this survey were analyzed using cyclomatic complexity to gain insight into the apparent complexity of the autoflight system from the perspective of the pilot. Mode transitions which had been identified as complex by pilots were found to have a high cyclomatic complexity. Further examination was made into a set of specific problems identified in aircraft: the lack of a consistent representation of automation, concern regarding appropriate feedback from the automation, and the implications of physical limitations on the autoflight systems. Mode transitions involved in changing to and leveling at a new altitude were identified across multiple aircraft by numerous pilots. Where possible, evaluation and verification of the behaviour of these autoflight mode transitions was investigated via aircraft-specific high fidelity simulators. Three solution approaches to concerns regarding autoflight systems, and mode transitions in particular, are presented in this thesis. The first is to use training to modify pilot behaviours, or procedures to work around known problems. The second approach is to mitigate problems by enhancing feedback. The third approach is to modify the process by which automation is designed. The Operator Directed Process forces the consideration and creation of an automation model early in the design process for use as the basis of the software specification and training.
by Sanjay Sridhar Vakil.
Ph.D.
39
Corcoran, Evangeline Mae. "Monitoring and modelling vulnerable wildlife populations using remotely piloted aircraft systems and machine learning." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/212423/1/Evangeline_Corcoran_Thesis.pdf.
Full textAbstract:
In this thesis a new method for monitoring wildlife using drones and machine learning was developed and used to accurately detect threatened koalas in natural, complex forest habitats for the first time. The new automated detection method was robust, efficient, and was not subject to biases affecting ground surveys or manual analysis of thermal images from drones. A new statistical modelling approach was also developed that allowed accurate estimates of abundance to be made from automated detections of wildlife in drone surveys.
40
Loeffler, Benjamin Haile. "Modeling and optimization of a thermosiphon for passive thermal management systems." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45960.
Full textAbstract:
An optimally designed thermosiphon for power electronics cooling is developed. There exists a need for augmented grid assets to facilitate power
routing and decrease line losses. Power converter augmented transformers (PCATs) are critically limited thermally. Conventional active cooling
system pumps and fans will not meet the 30 year life and 99.9% reliability required for grid scale implementation. This approach seeks to develop
a single-phase closed-loop thermosiphon to remove heat from power electronics at fluxes on the order of 10 - 15 W/cm2. The passive
thermosiphon is inherently a coupled thermal-fluid system. A parametric model and multi-physics design optimization code will be constructed to
simulate thermosiphon steady state performance. The model will utilize heat transfer and fluid dynamic correlations from literature. A particle
swarm optimization technique will be implemented for its performance with discrete domain problems. Several thermosiphons will be constructed,
instrumented, and tested to verify the model and reach an optimal design.
41
Cacciari, Matteo <1984>. "Model predictive control in thermal management of multiprocessor systems-on-chip." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5771/.
Full textAbstract:
MultiProcessor Systems-on-Chip (MPSoC) are the core of nowadays and next
generation computing platforms. Their relevance in the global market continuously
increase, occupying an important role both in everydaylife products (e.g.
smartphones, tablets, laptops, cars) and in strategical market sectors as aviation,
defense, robotics, medicine. Despite of the incredible performance improvements
in the recent years processors manufacturers have had to deal with issues, commonly
called “Walls”, that have hindered the processors development. After the
famous “Power Wall”, that limited the maximum frequency of a single core and
marked the birth of the modern multiprocessors system-on-chip, the “Thermal
Wall” and the “Utilization Wall” are the actual key limiter for performance improvements.
The former concerns the damaging effects of the high temperature
on the chip caused by the large power densities dissipation, whereas the second
refers to the impossibility of fully exploiting the computing power of the processor
due to the limitations on power and temperature budgets. In this thesis we
faced these challenges by developing efficient and reliable solutions able to maximize
performance while limiting the maximum temperature below a fixed critical
threshold and saving energy. This has been possible by exploiting the Model Predictive
Controller (MPC) paradigm that solves an optimization problem subject
to constraints in order to find the optimal control decisions for the future interval.
A fully-distributedMPC-based thermal controller with a far lower complexity
respect to a centralized one has been developed. The control feasibility and interesting
properties for the simplification of the control design has been proved
by studying a partial differential equation thermal model. Finally, the controller
has been efficiently included in more complex control schemes able to minimize
energy consumption and deal with mixed-criticalities tasks
42
Bergman, Emma. "Designing Thermal Management Systems For Lithium-Ion Battery Modules Using COMSOL." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-241899.
Full textAbstract:
In this thesis, a section of a lithium ion battery module, including five cells and an indirect liquid cooling system, was modelled in COMSOL Multiphysics 5.3a. The purpose of this study was to investigate the thermal properties of such a model, including heat generation per cell and temperature distribution. Additionally, the irreversible and reversible heat generation, the cell voltage and the internal resistance were investigated. The study also includes the relation between heat generation and C-‐rates, and an evaluation of COMSOL Multiphysics 5.3a as a software. It was found that having liquid cooling is beneficial for the thermal management, as the coolant flow helps to transfer away the heat generated within the battery. The results also show that it is important to not go below a set cell voltage at which the cell is considered fully discharged. If a control mechanism to stop the battery is not implemented, the generated heat, and consequently the temperature, increase drastically. COMSOL Multiphysics 5.3a was considered a suitable software for the modelling. For future research it is of interest to expand the model to a full scale module to fully investigate the temperature distribution where more cells are being cooled by the same coolant loop.
43
Wolfe, Neil A. "Development of a Tailored Flight Test Approach for small Unmanned Aircraft Systems." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2073.
Full textAbstract:
This document contains the details of a study conducted to determine an effective performance flight test approach specifically for small Unmanned Aircraft Systems (sUAS). This was done by taking proven procedures and documentation from the FAA and the Air Force for manned aircraft and tailoring them specifically for use with sUAS flight test programs. A ‘sUAS Flight Testing Handbook’ was created from the proceedings to aid commercial organizations and recreational developers conducting sUAS research without access to flight test experience. A performance flight test program was conducted with the AeroVironment RQ-20 Puma sUAS using the developed approach to verify that the ‘sUAS Flight Test Handbook’ was effective at guiding the test program safely and effectively. The development of the handbook, the results of the Puma Flight Test Program (PFTP), and the instructional ‘sUAS Flight Test Handbook’ itself are detailed throughout this report. The handbook includes a set of recommendations developed from experience with the PFTP that apply to both commercial and recreational developers of sUAS. A set of documentation is also provided in the form of instructional templates that plan the test program, report the results, and allow sUAS performance flight testing to be carried out safely and effectively.
44
Wang, Yong. "Microfluidic technology for integrated thermal management: micromachined synthetic jet." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/5438.
Full text
45
Xia, YuXin M. B. A. Sloan School of Management. "M28 Fixed wing transport aircraft cost reduction." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66038.
Full textAbstract:
Thesis (M.B.A.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Engineering Systems Division; in conjunction with the Leaders for Global Operations Program at MIT, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 146-148).
The M28 is a Polish short-takeoff-and-landing (STOL) light cargo aircraft developed in 1984 and currently built by PZL Mielec, a subsidiary of United Technology Corporation (UTC). There has been renewed interest in the product from military and commercial markets due to its impressive STOL capabilities. However, in order to become price-competitive, its cost would need to be reduced significantly. Multiple cost-reduction concepts have been proposed by the manufacturing and procurement groups. An Optimization Team was also formed to lead the cost-reduction effort. However, a more systematic approach is required in order to achieve the ambitious reduction goals. The proposed solution is to create a top-down systematic cost-reduction framework used to coordinate and prioritize the team's current bottom-up approach. A top-down cost reduction strategy was developed based on UTC Otis' Octopus Fishing concept. Such methodology, heavily finance driven, systematically breaks M28 into sub-systems, and prioritizes improvement recommendations based on cost-reduction potentials. It also leverages on the wealth of knowledge from global cross-functional teams to generate explosive amount of improvement recommendations. The sub-systems were benchmarked against competitors cost structures. The framework will be linked to concepts generated from the database to create a process that combine top-down and bottom-up approaches. After tasks were prioritized using the outlined framework, a three-prong approach was implemented to enhance cost reduction capability. Manufacturing of labor intensive parts such as nacelle deflection cover was automated using CNC machines. A set of commodity purchasing strategies were formulated for forgings, avionics, raw materials, interior and composite materials. Lastly, a discrete Kaizen event was described to aid redesign-for-manufacturing.
by Yuxin Xia.
S.M.
M.B.A.
46
Asokan, Aravind E. M. Massachusetts Institute of Technology. "System architecture for single-pilot aircraft in commercial air transport operations." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/106240.
Full textAbstract:
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, School of Engineering, System Design and Management Program, Engineering and Management Program, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 161-165).
Commercial flight operations have seen the consistent reduction of flight crew from five to two over the past several decades. As technology improves and airplanes become increasingly capable of flying themselves, this trend of crew reduction can be expected to continue. Single pilot operations in commercial air transport presents a range of benefits and challenges, some of which are explored in this thesis. While there has been some discussion of the concept of having a single pilot operate a complex aircraft, including an announcement by a regional jet manufacturer of their intent to realize the concept in the first half of the next decade, it is seen that there is a need to define architectures and compare them in different operational contexts. This examination of architectures is conducted by identifying high level concepts or architectural decisions mentioned in the literature reviewed thus far, and creating an architectural space containing the possible constrained combinations of architectural divisions. The architectural space is represented as a safety versus cost trade space, wherein different architectural combinations are compared against present day operations. An attempt is also made to identify possible off nominal situations and the ability of the different architectures to deal with them. Safety is studied primarily as a function of pilot workload, which is identified by studying the movement of flight operations processes from the first officer, who is eliminated. Cost in this context is regarded as a combination of acquisition costs and operating costs. The former is quantified by identifying likely changes in system complexity, while the latter is a combination of crew and new infrastructure costs. Moving to SPO requires taking into account the operating context. The analysis indicates that different classes of aircraft - widebodies, narrowbodies, and regional jets - have different levels of benefits and costs in moving to SPO. Capabilities of automation needs to improve drastically before the second human in the flight deck can be replaced, and this is borne out by the dominance of human centered concepts in the trade space. The analysis also indicates that regional aircraft may be prime candidates to move to SPO first, as most regional architectures generate positive savings.
by Aravind Asokan.
S.M. in Engineering and Management
47
Scofield, Jan W. (Jan William). "Benefit analysis and feasibility of ground collision avoidance systems on United States Air Force aircraft." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/41801.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management, 1995.Includes bibliographical references (p. 91-92).
This thesis examines a specific type of USAF aircraft mishaps - Controlled Flight Into Terrain (CFIT) mishaps. The thesis presents data on CFIT mishaps, causes, and efforts to reduce CFIT mishaps through the development and adoption of Ground Collision Avoidance Systems (GCAS) or similar designs - Ground Proximity Warning Systems (GPWS). GPWS exist today on some USAF aircraft, but many times these systems are inadequate (as evidenced by the continued occurrence of CFIT mishaps). Both ongoing and future initiatives by the USAF to adopt and develop better GPWS/GCAS systems were studied. An analysis was performed which studied the cost to the USAF (and the U.S. taxpayer) as a result of CFIT mishaps, and compared with an analysis of the cost to develop and implement improved GPWS/GCAS systems. The results show conclusively that installing GCAS/GPWS on a majority of USAF aircraft is cost effective. Technology exist today which could improve existing GPWS performance, and although efforts to improve GPWS are moving forward, some resistance does exist. Possible reasons for resistance of GCAS/GPWS adoption were studied and several recommendations were made on how to improve the adoption of these systems within the USAF.
by Jan W. Scofield.
S.M.
48
Butler, Patrick C. "Value proposition analysis for medium- and heavy- lift cargo unmanned aircraft systems." Thesis, Massachusetts Institute of Technology, 2019. https://hdl.handle.net/1721.1/122591.
Full textAbstract:
Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2019, In conjunction with the Leaders for Global Operations Program at MITThesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2019, In conjunction with the Leaders for Global Operations Program at MIT
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 99-109).
The majority of current unmanned aircraft system (UAS) research is focusing on small UAS operations at low altitude over rural and underpopulated areas. There is a gap in research about UAS greater than 55 pounds. The first unmanned aircraft to operate in this airspace is likely to be unmanned air cargo vehicles. This paper analyzes the commercial market opportunities for medium- and heavy-lift cargo UAS by developing value propositions for each viable market. A multi-criteria decision analysis (MCDA) tool was developed to analyze the value proposition for cargo UAS compared to other transportation vehicles. The MCDA tool evaluated the value generated from three different value attributes: cost, time, and vehicle characteristics. These were applied across fourteen different reference missions to assess the potential utilization of cargo UAS in those markets. The results of the analysis showed that a medium-lift cargo UAS is the best transportation vehicle for organ/blood transport, medical equipment transport, urgent delivery, remote delivery, and search and rescue operations. Heavy-lift cargo UAS proved to be the best transportation vehicle for oil rig delivery, HVAC service, and disaster relief. Additional findings showed that the most significant method to reduce cost for medium-lift cargo UAS is by applying autonomy and advanced command & control systems which facilitate the operation of multiple vehicles per operator. The most important consideration to reduce cost for heavy-lift cargo UAS is to increase the specific energy of the batteries used.
by Patrick C. Butler.
M.B.A.
S.M.
M.B.A. Massachusetts Institute of Technology, Sloan School of Management
S.M. Massachusetts Institute of Technology, Department of Aeronautics and Astronautics
49
Rudol, Piotr. "Increasing Autonomy of Unmanned Aircraft Systems Through the Use of Imaging Sensors." Licentiate thesis, Linköpings universitet, UASTECH – Teknologier för autonoma obemannade flygande farkoster, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71295.
Full textAbstract:
The range of missions performed by Unmanned Aircraft Systems (UAS) has been steadily growing in the past decades thanks to continued development in several disciplines. The goal of increasing the autonomy of UAS's is widening the range of tasks which can be carried out without, or with minimal, external help. This thesis presents methods for increasing specific aspects of autonomy of UAS's operating both in outdoor and indoor environments where cameras are used as the primary sensors. First, a method for fusing color and thermal images for object detection, geolocation and tracking for UAS's operating primarily outdoors is presented. Specifically, a method for building saliency maps where human body locations are marked as points of interest is described. Such maps can be used in emergency situations to increase the situational awareness of first responders or a robotic system itself. Additionally, the same method is applied to the problem of vehicle tracking. A generated stream of geographical locations of tracked vehicles increases situational awareness by allowing for qualitative reasoning about, for example, vehicles overtaking, entering or leaving crossings. Second, two approaches to the UAS indoor localization problem in the absence of GPS-based positioning are presented. Both use cameras as the main sensors and enable autonomous indoor ight and navigation. The first approach takes advantage of cooperation with a ground robot to provide a UAS with its localization information. The second approach uses marker-based visual pose estimation where all computations are done onboard a small-scale aircraft which additionally increases its autonomy by not relying on external computational power.
50
Telford, Rory. "Novel methods for improving fault protection & health management within advanced aircraft electrical power systems." Thesis, University of Strathclyde, 2017. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27950.
Full textAbstract:
The more-electric aircraft (MEA) concept is widely viewed as the next evolutionary step towards enabling the industry goal of developing optimised, fuel efficient aircraft. MEA have an increased dependency on electrical energy for distribution to secondary systems and, in order to service this increased dependence, the electrical power systems (EPS) are more complex with increased voltage distribution levels, power conversion stages and safety critical components compared with their conventional counterparts. These complexities will only increase in future platforms as they further embrace the MEA concept - the migration to increasingly novel, critical and complex EPS will incur several development and integration challenges. This thesis considers the fundamental challenge of maintaining high reliability standards within future aircraft EPS through the development of accurate and discriminative real-time protection systems which will react during fault conditions. Specifically, the thesis researches novel methods that improve real-time aircraft EPS protection and health management systems by 1) accurately diagnosing degraded faults before their progression to critical failure and 2) diagnosing faults that are difficult to detect using only conventional protection methods â in particular, series arc faults are considered. Within future aircraft EPS, the volume of operational data is expected to significantly increase beyond that of the conventional systems; consequently, the thesis focuses on the use of data-driven, machine learning based methods, to enable these extended functionalities of the EPS protection and health management systems. The types of machine learning modelling techniques that were chosen are explained and justified. Conventional protection methods are described, including a discussion on the difficulties in using them to detect both degraded fault modes and arcing conditions. The necessity to detect these types of faults in an accurate and timely manner is also discussed. One of the main contributions of the thesis is the proposal of the EPSmart method that can autonomously diagnose and isolate a multitude of degraded faults within an aircraft representative EPS. These degraded faults include intermittent and incipient conditions, which, in comparison to overcurrent faults, often lack the energy to be detected by conventional means. Early, and accurate, detection of these conditions will improve overall system health management and reliability and ensure safe operation of the aircraft. Further contribution is the design of the IntelArc method that can detect series arc faults within direct current supplied systems. Accurate detection of series arc faults is extremely challenging as, despite their presence being a serious fire hazard, they result in a decrease of load current. Although methods do exist for diagnosis of series arcing, there remain challenges with regards to accurate detection across different system configurations and operating conditions. The thesis shows the potential for IntelArc to provide accurate detection across a variety of configurations and operating conditions. While the thesis only describes the initial development of these novel methods, the significant conclusions are that application testing has shown the potential for them to enhance real-time network protection, fault tolerance and health management of aircraft EPS through detection of degraded fault and arcing conditions.