Tesi sul tema "Navigation"
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Lindgren, Anders. "Navigating Navigation : A Safety and Usability Evaluation of the Volvo P1 Navigation System". Thesis, Linköping University, Department of Computer and Information Science, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-4210.
Testo completoNavigation systems are today options provided by car manufacturers’ world wide and market predictions suggest that 25 percent of all cars produced by 2009 will have navigation systems installed. However, there are many human-interface issues concerning the use of these navigation systems. This thesis describes a study which evaluates and tests the safety and usability of the Volvo P1 navigation system and also contains suggestions on how the system and its controls should be designed to be safer and easier to use. This is done through heuristic evaluations and a Lane Change Test (LCT). The LCT is used to compare the level of driver distraction between the steering wheel control and remote control and also between common and advanced exercises in the system. Results from the study shows that there are no significant differences in distraction between using the steering wheel control or the remote control. The results also show that there are no significant differences in distraction between the common and advanced exercises. The results of the study are presented as a collection of design proposals that can be used to improve the system’s safety and usability.
Franz, Matthias O. "Minimalistic Visual Navigation = Minimalistische visuelle Navigation /". Düsseldorf : VDI-Verl, 1999. http://www.gbv.de/dms/bs/toc/266809243.pdf.
Testo completoTörnberg, Pontus. "GNSS independent navigation using radio navigation equipment". Thesis, Luleå tekniska universitet, Rymdteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-81212.
Testo completoIgoniderigha, Nseabasi Ekaette. "Data navigation and visualization : navigating coordinated multiple views of data". Thesis, Edinburgh Napier University, 2015. http://researchrepository.napier.ac.uk/Output/8832.
Testo completoBernelind, Sarah. "Navigation in Augmented Reality, Navigation i Augmented Reality". Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172907.
Testo completoFreider, Elias. "Crowd Navigation : Autonomous navigation in an urban environment". Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-169497.
Testo completoI detta examensarbete utvärderas och diskuteras strategier för navigering bland folk med hjälp av en självstyrd holonomisk robot. Fokus är satt på navigeringsproblemet i sig och närliggande ämnen som maskininlärning och reglerteknik behandlas ej även om en fördjupning på dessa områden vore nödvändigt för en praktisk implementation utanför den simulerade världen. Existerande strategier och algoritmer för navigering av dynamiska miljöer utvärderas genom datorsimuleringar i varierande miljöer. En ny algorithm presenteras och visar sig vara användbar i vissa situationer. Denna algoritm, ART, förutser folkmassans rörelser och använder denna information för att hitta bättre vägar till målet.
Knutsson, Pontus, e Oskar Georgsson. "Augmented Reality Navigation Compared to 2D Based Navigation". Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20499.
Testo completoFor almost three decades GPS coordinates and directions have been displayed with a top-down 2D view. At first in dedicated navigation systems, commercially used for driving, into today having GPS systems available in our everyday smartphones. The most common way to display the coordinates today are still by some sort of 2D view showing the user where it is and what roads/streets to take. This however has some problems that we believe can be solved using Augmented Reality combined with GPS. This paper sets out to answer the question if and how Augmented Reality displayed navigation can make it easier for pedestrians to navigate through a city compared to a 2D displayed navigation. In order to answer the question at hand this study presents a navigation application that combines the two technologies GPS and Augmented Reality which then is used in a user test. The results from the user tests and the questionnaire indicates that Augmented Reality based navigation is best used in scenarios where there are a lot of streets and it is hard to tell on a 2D map which street to take.
Werner, Martin. "Ubiquitous Navigation". Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-147950.
Testo completoMazaheri, Shima. "Indoor navigation". Thesis, Mittuniversitetet, Avdelningen för informationssystem och -teknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-32798.
Testo completoBäcklinder, Werf Karl, e Arteaga Jorge Antonio Anvar Gomez. "ForShore Navigation". Thesis, Linköpings universitet, Institutionen för teknik och naturvetenskap, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-96188.
Testo completoRapporten beskriver ett möjligt sätt för datafusion mellan vektor och rasterdata för att skapa ett tredimensionellt interaktivt kustlandskap. Datan är insamlad av två olika myndigheter och representerar ett utsnitt av verkliga mätningar. Vektordata utgörs av information som tidigare extraherats från ett ENC sjökort samt information från lantmäteriests webtjänst det Digitala Kartbiblioteket. Rasterdata kommer i form utav höjddata och ortobild från digitala kartbiblioteket. OpenSceneGraph har används för att visualisera sjökortet och wxWindows som bas för användargränssnittet. Den metod som används vid skapandet av terräng ger ett resultat som avviker som mest 0.07 meter från det extraherade sjökortet. Punkter där detta fel uppstår är lätt identifierbara.
Absalyamov, Artur, e Jimmy Gladh. "Navigation Robot". Thesis, Uppsala universitet, Signaler och system, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-416934.
Testo completoCollins, Andrew. "Distributed navigation". Thesis, University of Liverpool, 2013. http://livrepository.liverpool.ac.uk/12415/.
Testo completoChin, Yu-Chi. "The Navigation Data Logger for a Suitcase Navigation System". Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/28391.
Testo completoMaziol, Timotheé. "Fusion of imaging and inertial navigation system for navigation". Thesis, KTH, Optimeringslära och systemteori, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-234685.
Testo completoDenna rapport presenterar det arbete som utförs på Safran Electronics & Defense I samband med mitt masterprojekt-praktik. Visionshybridisering med tröghetssystem har stor potential I navigationssystem. Detta examensarbete undersöker denna potential och utvärderar den på reella uppgifter om banor för en specifik hybridisering: Löst kopplat via ett ”Extended Kalman Filter”. Visionshybridiseringen utvecklas för att begränsa driften av positionen för den senaste GPS-hybridiseringen när GPS inte är tillgänglig. Avhandlingen presenterar hybridiseringstester på olika banor som antingen simulerades från början eller rekonstruerades från reell fordonsledning (stimulering). Att använda verkliga data för forskningsarbete innebär tekniska utmaningar. Vissa presenteras, liksom de föreslagna lösningarna för att hantera dem.
Štefanisko, Ivan. "Integration of inertial navigation with global navigation satellite system". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-221167.
Testo completoHenriksson, Simon, Mats Lindqvist e Martin Söderblom. "E-newspaper Navigation - Designing navigational aids for a new electronic medium". Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-1831.
Testo completoIn this paper we examine the need of navigational aids when designing interfaces for e-newspapers
– newspapers presented on a digital paper built on E-Ink technology. By reviewing literature on
navigation, and by handling input from both newspaper designers and potential e-newspaper
adopters, we have suggested a number of navigational aids for the future e-newspaper. Our
suggestions have been tested through a prototype using a modification of the Cooperative
Usability Testing model (CUT) on a total of fifteen potential users. The results show that most
users prefer a linear organization of the e-newspaper. To render a sense of depth in this flat
medium, page-numbering is essential. Several different interaction possibilities will also be
needed to ease the navigation and our suggestions include a blend of page-turning and hyper
linking, combined with an index to give the user a better overview of the content.
Jonsson, William. "Navigating Robot : Indoor Navigation Using Color Tracking and Ultrasonic Range Finders". Thesis, KTH, Maskinkonstruktion (Inst.), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-184496.
Testo completoNavigering och lokalisering inomhus är ett hett forskningsområde både inom vetenskapen och ingenjörstillämpningar. Exempel på system som kan förbättras med sådan teknik är robotar som assisterar människor i hemmet samt automatisering av industrirobotar som är fria att röra sig över golvytor [Jensen, 2001]. Detta kandidatexamensprojekt undersöker möjligheterna och begränsningarna av navigering inomhus för en autonom robot med hjälp av färg-igenkännande bildbehandling och avståndssensorer. Navigeringen sker med hjälp av två riktmärken: en visuell referens monterad på en plan vägg och avståndet mellan robot och vägg. Robotens interna styrelektronik, sensorer samt mjukvara är alla open source. Bredden av projektet begränsas av villkoren att navigationen sker på en plan yta utan hinder samt tillgång till en plan vägg med en visuell referens. Slutgiltiga systemets navigationssäkerhet kontrollerades och mättes empiriskt och uppskattades till att ha en medelavvikelse på ± 1 cm och ± 4.6 cm för x respektive y-axeln.
Andrade, Alessandra Arrojado Lisbôa de. "Navigating into the new millennium : the global navigation satellite system regulatory framework". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ64258.pdf.
Testo completoKarabork, Alper. "Terrain Aided Navigation". Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612493/index.pdf.
Testo completoaid is used to supply external measurements and dierent algorithms are used to provide the most probable corrections to the state estimate using all data. One of the integrated navigation approaches is Terrain Aided Navigation (TAN). Terrain Aided Navigation is a technique to estimate the position of a moving vehicle by comparing the measured terrain profile under the vehicle to a stored map, DTED. This thesis describes the theoretical aspects implementation of a simulation environment, simulations of the implemented Kalman Filtering TAN algorithms with developed INS model. In order to perform the study, first a thorough survey of the literature on TAN navigation algorithms is performed. Then, we have developed a dynamics simulation environment. A flight profile generator is designed. Since, the main issue of this work is to correct INS, an Strapdown INS model developed using Matlab INS Toolbox. Therefore, to model a Strapdown INS, mathematical equations of INS system are derived and they are linearized to form linear error model. In addition, a radar altimeter simulator is also developed that provides measurement to the error dynamics. Then, a Kalman filter structure is designed and implemented using Matlab. The simulations are done with dierent linearization approaches using Kalman filter structure. Finally, the performance of the implemented algorithms are evaluated.
Pittas, Marios. "Navigation in hypertext". Thesis, Queen Mary, University of London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273848.
Testo completoNegahdaripour, Shahriar. "Direct passive navigation". Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14939.
Testo completoMICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE
Bibliography: leaves 219-225.
by Shahriar Negahdaripour.
Ph.D.
Stelzer, Roland. "Autonomous sailboat navigation". Thesis, De Montfort University, 2012. http://hdl.handle.net/2086/7364.
Testo completoKirby, Rachel. "Social Robot Navigation". Research Showcase @ CMU, 2010. http://repository.cmu.edu/dissertations/552.
Testo completoScheding, Steven. "High integrity navigation". Phd thesis, Department of Mechanical and Mechatronic Engineering, 1998. http://hdl.handle.net/2123/6768.
Testo completoPadovani, Stephania. "The effects of navigational aids on users' navigation strategies in hypertext systems". Thesis, Loughborough University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251068.
Testo completoHolmquist, John. "NAVIGATION AIDS IN ROUTE TRAINING: INCREASE NAVIGATION SPEED, DECREASE ROUTE RETENTION?" Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4014.
Testo completoPh.D.
Other
Engineering and Computer Science
Modeling and Simulation
Müller, Jörg [Verfasser], e Wolfram [Akademischer Betreuer] Burgard. "Autonomous navigation for miniature indoor airships = Autonome Navigation für Miniaturluftschiffe in Innenräumen". Freiburg : Universität, 2013. http://d-nb.info/1114829153/34.
Testo completoArisut, Omer T. "Effects of navigation aids on human error in a complex navigation task". Thesis, Monterey, California. Naval Postgraduate School, 2002. http://hdl.handle.net/10945/6072.
Testo completoThis thesis investigates land navigators' performance differences in land navigation when different navigation aids are used. The question that this thesis attempts to answer is whether the use of Global Positioning System (GPS) in land navigation results in a performance dependency, and, if so, whether that dependency adversely affects performance. To address these questions an experiment was conducted to see if the use of GPS makes map and compass training obsolete. The participants were divided into two training groups; map + compass navigation and GPS navigation. The experiment studied human performance differences, human error, and transfer of training while participants navigated using only GPS in the first part, and map + compass in the second part of the experiment. The results suggested that map +compass training is always preferable. A map +compass native land navigator outperforms a GPS native land navigator when GPS is not accessible. This evidence suggests that a military land navigator, in particular, should know both navigation techniques and should be able to switch from one to the other without any hesitation.
Bolduc, Carole R. M. (Carole Rita Marie) Carleton University Dissertation Engineering Mechanical and Aerospace. "Self-alignment and navigation algorithms for DREO navigation laboratory heading reference unit". Ottawa, 1995.
Cerca il testo completoEne, Alexandru. "Utilization of modernized global navigation satellite systems for aircraft-based navigation integrity /". May be available electronically:, 2009. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
Testo completoWeisberg, Steven Marc. "WHERE AM I? INDIVIDUAL DIFFERENCES IN MEMORY, NAVIGATION ABILITY, AND NAVIGATION STRATEGY". Diss., Temple University Libraries, 2014. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/308490.
Testo completoPh.D.
Navigation proficiency - the ability to find and recall new and familiar locations - varies widely among individuals (e.g., Schinazi, Epstein, Nardi, Newcombe, & Shipley, 2013; Weisberg, Schinazi, Newcombe, Shipley, & Epstein, 2014). The cognitive processes that support effective navigation have been theoretically sketched out (e.g., Wolbers & Hegarty, 2010), but how do those processes contribute to aspects of and individual differences in navigation behavior? Using a virtual environment to assess navigation proficiency (Weisberg et al., 2014), we conducted two studies to investigate whether individual differences in navigating meaningfully relate to memory capacity (Study1) and navigation strategy (Study 2). Results from Study 1 suggest that working memory capacity may limit some participants' ability to build accurate cognitive maps. Using a virtual environment paradigm based on the rodent T-maze (Marchette, Bakker, & Shelton, 2011), Study 2 shows that good navigators do not prefer to use a place-based strategy over a response-based strategy, but there was an interaction between strategy selection and goals found. Good navigators who used a place-based strategy found more goals than good navigators who used a response-based strategy; the opposite was true for bad navigators. Emerging from this set of studies is a richer picture of how individual differences in cognitive traits (i.e., working memory capacity), and strategy choice relate to navigation proficiency.
Temple University--Theses
Satanek, Brandon L. "The Effects of Multidimensional Navigational Aids and Individual Differences on WWW Hypertext Navigation". Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36690.
Testo completoMaster of Science
Weischede, Frank. "Fehlerminimale Navigation lunarer Raumfahrzeuge". [S.l.] : [s.n.], 2007. http://opus.kobv.de/tuberlin/volltexte/2007/1555.
Testo completoRosander, Peter. "Camera Based Terrain Navigation". Thesis, Linköping University, Linköping University, Automatic Control, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-16953.
Testo completoThe standard way for both ground and aerial vehicles to navigate is to use anInertial Navigation System, INS, containing an Inertial Measurement Unit, IMU,measuring the acceleration and angular rate, and a GPS measuring the position.The IMU provides high dynamic measurements of the acceleration and the angularrate, which the INS integrates to velocity, position and attitude, respectively.While being completely impossible to jam, the dead-reckoned estimates will driftaway, i.e., the errors are unbounded. In conjunction with a GPS, providing lowdynamic updates with bounded errors, a highly dynamic system without any driftis attained. The weakness of this system is its integrity, since the GPS is easilyjammed with simple equipment and powered only by a small standard battery.When the GPS is jammed this system falls back into the behavior of the INS withunbounded errors. To counter this integrity problem a camera can be used aseither a back up to the GPS or as its replacement. The camera provides imageswhich are then matched versus a reference, e.g., a map or an aerial photo, to getsimilar estimates as the GPS would provide. The camera can of course also bejammed by blocking the view of the camera with smoke. Bad visibility can alsooccur due to bad weather, but a camera based navigation system will definitelybe more robust than one using GPS.This thesis presents two ways to fuse the measurements from the camera and theIMU, both of them utilizing the Harris corner detector to find point correspondencesbetween the camera image and an aerial photo. The systems are evaluatedby simulated data mimicking both a low and a high accuracy IMU and a camerataking snapshots of the aerial photo. Results show that for the simulated cameraimages the implemented corner detector works fine and that the overall result iscomparable to using a GPS.
Standardsättet för både flygande och markgående fordon att navigera är att användaett tröghetsnavigeringssystem, innehållande en IMU som mäter acceleration ochvinkelhastighet, tillsammans med GPS. IMU:n tillhandahåller högfrekventa mätningarav acceleration och vinkelhastighet som integreras till hastighet, positionoch attityd. Ett sådant system är omöjligt att störa, men lider av att de dödräknadestorheterna hastighet, position och attityd, med tiden, kommer att driva ivägifrån de sanna värdena. Tillsammans med GPS, som ger lågfrekventa mätningarav positionen, erhålls ett system med god dynamik och utan drift. Svagheten i ettvvisådant system är dess integritet, då GPS enkelt kan störas med enkel och billigutrustning. För att lösa integritetsproblemet kan en kamera användas, antingensom stöd eller som ersättare till GPS. Kameran tar bilder som matchas gentemoten referens ex. en karta eller ett ortofoto. Det ger liknande mätningar som de GPSger. Ett kamerabaserat system kan visserligen också störas genom att blockerasynfältet för kameran med exempelvis rök. Dålig sikt kan också uppkomma pågrund av dåligt väder eller dimma, men ett kamerabaserat system kommer definitivtatt vara robustare än ett som använder GPS.Det här examensarbetet presenterar två sätt att fusionera mätningar från etttröghetssystem och en kamera. Gemensamt för båda är att en hörndetektor, Harriscorner detector, används för att hitta korresponderande punkter mellan kamerabildernaoch ett ortofoto. Systemen utvärderas på simulerat data. Resultatenvisar att för simulerade data så fungerar den implementerade hörndetektorn ochatt prestanda i nivå med ett GPS-baserat system uppnås.
Noreikis, Marius. "Image Based Indoor Navigation". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177344.
Testo completoForskare har de senaste åren framfört olika inomhusnavigations- och lokaliseringssystem. Dock kräver lösningar som använder WiFi eller radiofrekvens identifikation en utbyggdnad av stödjande infrastruktur i navigationsområdena. Även teknikerna som används lider av precisionsfel. I det här examensarbetet redovisar vi en ny taktik för inomhusnavigation som använder sig av datorvisualiserings Structure from Motion-tekniker. Vi implementerade en navigationssystemsprototyp som använder bilder för att bygga en navigationskarta och kartlägga användarens position. I vårt klient-server baserat system är en klient en mobilapplikation som tillåter användaren att hitta sin position genom att ta en bild. På server-sidan hanteras kartor, lokaliseringsförfrågor och mättningar av förfrågorna och algoritmerna som används. Systemet har lyckats navigera genom Aalto Universitets datorvetenskapsbiblioteket. Vi lyckades uppnå en felmarginal pa 0.26 meter för lyckade lokaliseringsbilder. I arbetet redovisar vi utmaningar som vi har löst för att anpassa datorvisualiseringstekniker for lokalisering. Vi har även diskuterat potentialla framtida implementationer for att utvidga systemet.
Diepenbrock, Stefan, Timo Ropinski e Klaus Hinrichs. "Context-aware volume navigation". University of Münster, Germany, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-92865.
Testo completoFreeman, Robin. "Analysis of Avian Navigation". Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504344.
Testo completoBassett, Robert M. "Automated satellite image navigation". Thesis, Monterey, California. Naval Postgraduate School, 1992. http://hdl.handle.net/10945/23552.
Testo completoThis study investigated the automated satellite image navigation method (Auto-Avian) developed and tested by Spaulding (1990) at the Naval Postgraduate School. The Auto-Avian method replaced the manual procedure of selecting Ground Control Points (GCPs) with an autocorrelation process that utilizes the World Vector Shoreline (WVS) provided by the Defense Mapping Agency (DMA) as a "string" of GCPs to rectify satellite images. The automatic cross-correlation of binary references (WVS) and search (image) windows eliminated the subjective error associated with the manual selection of GCPs and produced accuracies comparable to the manual method. This study expanded the scope of Spaulding's (1990) research. The worldwide application of the Auto-Avian method was demonstrated in three world regions (eastern North Pacific Ocean, eastern North Atlantic Ocean, and Persian Gulf). Using five case studies, the performance of the Auto-Avian method on "less than optimum" images (i.e., islands, coastlines affected by lateral distortion and/or cloud cover) was investigated. The result indicated that utilizing the Auto-Avian method on these "less than optimum images" could achieve navigational accuracies approaching those obtained by Spaulding (1990).
Schwartz, Benjamin Matthew. "Biometric Navigation with Ultrasound". Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10431.
Testo completoLangford, Duncan. "Broadbutton linking hypertext navigation". Thesis, University of Kent, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303108.
Testo completoRoth, Daniel R. (Daniel Risner) 1979. "Vision based robot navigation". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/17978.
Testo completoIncludes bibliographical references (p. 53-54).
In this thesis we propose a vision-based robot navigation system that constructs a high level topological representation of the world. A robot using this system learns to recognize rooms and spaces by building a hidden Markov model of the environment. Motion planning is performed by doing bidirectional heuristic search with a discrete set of actions that account for the robot's nonholonomic constraints. The intent of this project is to create a system that allows a robot to be able to explore and to navigate in a wide variety of environments in a way that facilitates goal-oriented tasks.
by Daniel R. Roth.
M.Eng.
Wang, Tianheng Ph D. Massachusetts Institute of Technology. "Network navigation with scheduling". Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/115653.
Testo completoCataloged from PDF version of thesis.
Includes bibliographical references (pages 155-164).
Network navigation is a promising paradigm for enabling location-awareness in dynamic wireless networks. A wireless navigation network consists of agents (mobile with unknown locations) and anchors (possibly mobile with known locations). An agent can estimate its locations based on inter- and intra-node measurements, as well as prior knowledge. In the presence of limited wireless resources, only a subset rather than all of the node pairs can perform inter-node measurements at a time. The procedure of selecting node pairs at different time instants for inter-node measurements, referred to as network scheduling, affects the time evolution of agents' localization errors. The key to achieve high navigation accuracy and efficient channel usage is to maximize the benefit from agents' inter-node measurements. Therefore, it is critical to design scheduling algorithms that decide for each agent with whom and when to perform inter-node measurements. This thesis introduces situation-aware scheduling that exploits network states to adaptively schedule agents' inter-node measurements. In particular, an analytical framework is developed to determine the effects of scheduling strategies and network settings on the localization error evolution. Furthermore, efficient and distributed situation-aware scheduling algorithms tailored for wireless navigation networks are designed, leading to high navigation accuracy and efficient channel usage. The first part of the thesis develops an analytical framework to determine the localization error evolution as a function of scheduling algorithms and network settings. In particular, both sufficient and necessary conditions for the boundedness of the error evolution are provided. Furthermore, opportunistic and random situation-aware scheduling strategies are proposed, and bounds on the corresponding time-averaged network localization errors are derived. These strategies are proved to be optimal in terms of the error scaling with the number of agents. Finally, the navigation accuracy is shown to be improved by sharing the wireless resources among multiple measurement pairs instead of allocating all the resources to a single pair at a time. The second part of the thesis designs efficient slotted and unslotted situation-aware scheduling algorithms tailored for wireless navigation networks based on the analytical results from the first part. The algorithm parameters, such as access probabilities and access rates, are optimized based on bounds for the time-averaged network localization error (NLE). The proposed algorithms lead to significant performance improvement compared with scheduling algorithms from wireless communication networks. The third part of the thesis develops a framework for the design of random-access-based distributed and asynchronous scheduling algorithms for wireless navigation networks, in which the channel access probabilities are optimized based on the evolution of agents' localization errors. The proposed algorithm achieves higher navigation accuracy and more efficient channel usage than the commonly used carrier sensing multiple access (CSMA) algorithm from wireless communication networks, at the cost of minimal communication overhead and computational complexity. The performance improvement is shown via numerical and experimental results. The contributions of this thesis provide a framework for the analysis and design of scheduling algorithms for wireless navigation networks, leading to high-accuracy, efficient, and flexible network navigation.
by Tianheng Wang.
Ph. D.
Bingham, Brian S. (Brian Steven) 1973. "Precision autonomous underwater navigation". Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29629.
Testo completoIncludes bibliographical references (p. 175-185).
Deep-sea archaeology, an emerging application of autonomous underwater vehicle (AUV) technology, requires precise navigation and guidance. As science requirements and engineering capabilities converge, navigating in the sensor-limited ocean remains a fundamental challenge. Despite the logistical cost, the standards of archaeological survey necessitate using fixed acoustic transponders - an instrumented navigation environment. This thesis focuses on the problems particular to operating precisely within such an environment by developing a design method and a navigation algorithm. Responsible documentation, through remote sensing images, distinguishes archaeology from salvage, and fine-resolution imaging demands precision navigation. This thesis presents a design process for making component and algorithm level tradeoffs to achieve system-level performance satisfying the archaeological standard. A specification connects the functional requirements of archaeological survey with the design parameters of precision navigation. Tools based on estimation fundamentals - the Cram6r-Rao lower bound and the extended Kalman filter - predict the system-level precision of candidate designs. Non-dimensional performance metrics generalize the analysis results. Analyzing a variety of factors and levels articulates the key tradeoffs: sensor selection, acoustic beacon configuration, algorithm selection, etc. The abstract analysis is made concrete by designing a survey and navigation system for an expedition to image the USS Monitor. Hypothesis grid (Hgrid) is both a representation of the sensed environment and an algorithm for building the representation. Range observations measuring the line-of-sight distance between two acoustic transducers are subject to multipath errors and spurious returns.
The quality of this measurement is dependent on the location of the estimator. Hgrids characterize the measurement quality by generating a priori association probabilities - the belief that subsequent measurements will correspond to the direct-path, a multipath, or an outlier - as a function of the estimated location. The algorithm has three main components: the mixed-density sensor model using Gaussian and uniform probability distributions, the measurement classification and multipath model identification using expectation-maximization (EM), and the grid-based spatial representation. Application to data from an autonomous benthic explorer (ABE) dive illustrates the algorithm and shows the feasibility of the approach.
by Brian Steven Bingham.
Ph.D.
Smith, Christopher Michael 1969. "Integrating mapping and navigation". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/50047.
Testo completoDryer, Jay E. (Jay Edward) 1970. "Robust autonomous vehicle navigation". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/91363.
Testo completoWystrach, Antoine. "Visual navigation in ants". Toulouse 3, 2011. http://thesesups.ups-tlse.fr/1707/.
Testo completoNavigating efficiently in the outside world requires many cognitive abilities like extracting, memorising, and processing information. The remarkable navigational abilities of insects are an existence proof of how small brains can produce exquisitely efficient, robust behaviour in complex environments. During their foraging trips, insects, like ants or bees, are known to rely on both path integration and learnt visual cues to recapitulate a route or reach familiar places like the nest. The strategy of path integration is well understood, but much less is known about how insects acquire and use visual information. Field studies give good descriptions of visually guided routes, but our understanding of the underlying mechanisms comes mainly from simplified laboratory conditions using artificial, geometrically simple landmarks. My thesis proposes an integrative approach that combines 1- field and lab experiments on two visually guided ant species (Melophorus bagoti and Gigantiops destructor) and 2- an analysis of panoramic pictures recorded along the animal's route. The use of panoramic pictures allows an objective quantification of the visual information available to the animal. Results from both species, in the lab and the field, converged, showing that ants do not segregate their visual world into objects, such as landmarks or discrete features, as a human observers might assume. Instead, efficient navigation seems to arise from the use of cues widespread on the ants' panoramic visual field, encompassing both proximal and distal objects together. Such relatively unprocessed panoramic views, even at low resolution, provide remarkably unambiguous spatial information in natural environment. Using such a simple but efficient panoramic visual input, rather than focusing on isolated landmarks, seems an appropriate strategy to cope with the complexity of natural scenes and the poor resolution of insects' eyes. Also, panoramic pictures can serve as a basis for running analytical models of navigation. The predictions of these models can be directly compared with the actual behaviour of real ants, allowing the iterative tuning and testing of different hypotheses. This integrative approach led me to the conclusion that ants do not rely on a single navigational technique, but might switch between strategies according to whether they are on or off their familiar terrain. For example, ants can recapitulate robustly a familiar route by simply aligning their body in a way that the current view matches best their memory. However, this strategy becomes ineffective when displaced away from the familiar route. In such a case, ants appear to head instead towards the regions where the skyline appears lower than the height recorded in their memory, which generally leads them closer to a familiar location. How ants choose between strategies at a given time might be simply based on the degree of familiarity of the panoramic scene currently perceived. Finally, this thesis raises questions about the nature of ant memories. Past studies proposed that ants memorise a succession of discrete 2D 'snapshots' of their surroundings. Contrastingly, results obtained here show that knowledge from the end of a foraging route (15 m) impacts strongly on the behaviour at the beginning of the route, suggesting that the visual knowledge of a whole foraging route may be compacted into a single holistic memory. Accordingly, repetitive training on the exact same route clearly affects the ants' behaviour, suggesting that the memorised information is processed and not 'obtained at once'. While navigating along their familiar route, ants' visual system is continually stimulated by a slowly evolving scene, and learning a general pattern of stimulation rather than storing independent but very similar snapshots appears a reasonable hypothesis to explain navigation on a natural scale; such learning works remarkably well with neural networks. Nonetheless, what the precise nature of ants' visual memories is and how elaborated they are remain wide open question. Overall, my thesis tackles the nature of ants' perception and memory as well as how both are processed together to output an appropriate navigational response. These results are discussed in the light of comparative cognition. Both vertebrates and insects have resolved the same problem of navigating efficiently in the world. In light of Darwin's theory of evolution, there is no a priori reason to think that there is a clear division between cognitive mechanisms of different species. The actual gap between insect and vertebrate cognitive sciences may result more from different approaches rather than real differences. Research on insect navigation has been approached with a bottom-up philosophy, one that examines how simple mechanisms can produce seemingly complex behaviour. Such parsimonious solutions, like the ones explored in the present thesis, can provide useful baseline hypotheses for navigation in other larger-brained animals, and thus contribute to a more truly comparative cognition
Yue, Weiya Ph D. "Improving Dynamic Navigation Algorithms". University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1368028468.
Testo completoSpangenberg, Mariana. "Safe navigation for vehicles". Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT022H/document.
Testo completoSatellite navigation has acquired an increased importance during these last years, on the one hand due to the imminent appearance of the European GALILEO system that will complement the American GPS, and on the other hand due to the great success it has encountered in the commercial civil market. An important part of this success is based on the technological development at the receiver level that has rendered satellite navigation possible even in difficult environments. Today's objective is to prepare the utilisation of this kind of signals for land vehicle applications demanding high precision positioning. One of the main challenges within this research domain, which cannot be addressed by classical coupling techniques, is related to the system capability to provide reliable position estimations. The enhancement in dead-reckoning technologies (i.e. size reduction of MEMS-based sensors or gyroscopes) cannot all by itself reach the necessary confidence levels if exploited with classical localization and integration algorithms. Indeed, these techniques provide a position estimation whose reliability or confidence level it is very difficult to quantify. The feasibility of these applications relies not only on an extensive research to enhance the navigation algorithm performances in harsh scenarios, but also and in parallel, on the possibility to maintain, thanks to the presence of additional sensors, a high confidence level on the position estimation even in the absence of satellite navigation signals
Bagci, Sinan. "Quellcode-Navigation in Gravis". [S.l. : s.n.], 2004. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB11730058.
Testo completoSpaulding, Brian C. "Automatic satellite image navigation". Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA240895.
Testo completoThesis Advisor(s): Wash, C. H. Second Reader: Schnebele, K. J. "September 1990." Description based on title screen as viewed on December 22, 2009. DTIC Descriptor(s): Radiometers, Navigation Reference, Interactions, Accuracy, Theses, Identification, Navigation, Images, Searching, Navigation Satellites, Artificial Satellites, Windows, Vector Analysis, Operators(Personnel), Earth(Planet), Birds, Matching, Automatic Pilots, Shores, Position(Location), Global. DTIC Identifier(s): Satellite Navigation, Program Listings. Author(s) subject terms: Image navigation, binary correlation, automatic landmarking. Includes bibliographical references (p. 78-81). Also available in print.