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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Location Based Service Framework for Pedestrian Navigation

Wieczorek, Natalia January 2011 (has links)
Pedestrian navigation is an emerging technology with high growth market potential. In this report, we present a location based service framework for pedestrian navigation that uses smart phones as client devices and is deployed on an existing Wi-Fi infrastructure in a building. The thesis describes methods and technologies that are used for pedestrian navigation and how they can be combined to achieve an accurate and reliable solution to the navigation problem. A final evaluation indicated that the service can be used in variety of places like university campuses, shopping malls and dense urban areas.
2

Tactile displays for pedestrian navigation

Srikulwong, Mayuree January 2012 (has links)
Existing pedestrian navigation systems are mainly visual-based, sometimes with an addition of audio guidance. However, previous research has reported that visual-based navigation systems require a high level of cognitive efforts, contributing to errors and delays. Furthermore, in many situations a person’s visual and auditory channels may be compromised due to environmental factors or may be occupied by other important tasks. Some research has suggested that the tactile sense can effectively be used for interfaces to support navigation tasks. However, many fundamental design and usability issues with pedestrian tactile navigation displays are yet to be investigated. This dissertation investigates human-computer interaction aspects associated with the design of tactile pedestrian navigation systems. More specifically, it addresses the following questions: What may be appropriate forms of wearable devices? What types of spatial information should such systems provide to pedestrians? How do people use spatial information for different navigation purposes? How can we effectively represent such information via tactile stimuli? And how do tactile navigation systems perform? A series of empirical studies was carried out to (1) investigate the effects of tactile signal properties and manipulation on the human perception of spatial data, (2) find out the effective form of wearable displays for navigation tasks, and (3) explore a number of potential tactile representation techniques for spatial data, specifically representing directions and landmarks. Questionnaires and interviews were used to gather information on the use of landmarks amongst people navigating urban environments for different purposes. Analysis of the results of these studies provided implications for the design of tactile pedestrian navigation systems, which we incorporated in a prototype. Finally, field trials were carried out to evaluate the design and address usability issues and performance-related benefits and challenges. The thesis develops an understanding of how to represent spatial information via the tactile channel and provides suggestions for the design and implementation of tactile pedestrian navigation systems. In addition, the thesis classifies the use of various types of landmarks for different navigation purposes. These contributions are developed throughout the thesis building upon an integrated series of empirical studies.
3

Fusing the information from two navigation systems using an upper bound on their maximum spatial separation

Skog, Isaac, Nilsson, John-Olof, Zachariah, Dave, Händel, Peter January 2012 (has links)
A method is proposed to fuse the information from two navigation systems whose relative position is unknown, but where there exists an upper limit on how far apart the two systems can be. The proposed information fusion method is applied to a scenario in which a pedestrian is equipped with two foot-mounted zero-velocity-aided inertial navigation systems; one system on each foot. The performance of the method is studied using experimental data. The results show that the method has the capability to significantly improve the navigation performance when compared to using two uncoupled foot-mounted systems. / <p>QC 20121221</p>
4

Automated creation of pedestrian route descriptions

Schroder, Catherine Jane January 2013 (has links)
Providing unambiguous, succinct descriptions of routes for pedestrians to follow is very challenging. Route descriptions vary according to many things, such as route length and complexity, availability of easily identifiable landmarks, and personal preferences. It is well known that the inclusion of a variety of landmarks facilitates route following – either at key decision points, or as a confirmatory cue. Many of the existing solutions, however, behave like car navigation systems and do not include references to such landmarks. The broader ambition of this research is the automatic generation of route descriptions that cater specifically to the needs of the pedestrian. More specifically this research describes empirical evidence gathered to identify the information requirements for an automated pedestrian navigation system. The results of three experiments helped to identify the criteria that govern the relative saliency of features of interest within an urban environment. There are a large variety of features of interest (together with their descriptions) that can be used as directional aids within route descriptions (for example buildings, statues, monuments, hills, and roads). A set of variables were developed in order to measure the saliency of the different classes of features. The experiments revealed that the most important measures of saliency included name, size, age, and colour. This empirical work formed the basis of the development of a pedestrian navigation system that incorporated the automatic identification of features of interest using the City of Edinburgh as the study area. Additionally the system supported the calculation of the saliency of a feature of interest, the development of an intervisibility model for the route to be navigated to determine the best feature of interest to use at each decision point along the route. Finally, the pedestrian navigation system was evaluated against route descriptions gathered from a random set of individuals to see how efficiently the system reflected the more natural and richer route description that people typically generate. This work shows that modelling features of interest is the key to the automatic generation of route descriptions that can be readily understood and followed by pedestrians.
5

Low-Cost Navigation Systems : A Study of Four Problems

Skog, Isaac January 2009 (has links)
Today the area of high-cost and high-performance navigation for vehicles is a well-developed field. The challenge now is to develop high-performance navigation systems using low-cost sensortechnology. This development involves problems spanning from signal processing of the dirty measurements produced by low-costsensors via fusion and synchronization of information produced by a large set of diverse sensors, to reducing the size and energyconsumption of the systems. This thesis examines and proposessolutions to four of these problems. The first problem examined is the time synchronizing of the sensordata in a global positioning system aided inertial navigationsystem in which no hardware clock synchronization is possible. A poor time synchronization results in an increased mean squareerror of the navigation solution and expressions for calculating this mean square error are presented. A method to solve the timesynchronization issue in the data integration software is proposed. The potential of the method is illustrated with tests onreal-world data that are subjected to timing errors. The second problem examined is the achievable clocksynchronization accuracy in a sensor network employing a two-waymessage exchange model. The Cramer-Rao bound for the estimation of the clock parameters is derived and transformed in to a lower bound on the mean square error of the clock offset.Further, an approximate maximum likelihood estimator for the clockparameters is proposed. The estimator is shown to be of low complexity and to have a mean square error in the vicinity of the Cramer-Rao bound. The third problem examined is the detection of the time epochswhen zero-velocity updates can be applied in a foot-mountedpedestrian navigation system. Four general likelihood ratio testsfor detecting when the navigation system is stationary based onthe inertial measurement data are studied. The performance of thefour detectors is evaluated using levelled ground, forward-gaitdata. The results show that the signals from the gyroscopes holdthe most reliable information for the zero-velocity detection. The fourth problem examined is the calibration of a low-costinertial measurement unit. A calibration procedure that relaxesthe accuracy requirements of the orientation angles the inertialmeasurement unit must be placed in during the calibration isstudied. The proposed calibration method is compared with theCramer-Rao bound for the case when the inertial measurementunit is rotated into precisely controlled orientations. Simulationresults show that the mean square error of the estimated sensormodel parameters reaches the Cramer-Rao bound within fewdecibels. Thus, the proposed method may be acceptable for a widerange of low-cost applications. / QC 20100810
6

Der Einsatz von Augmented Reality in der Fußgängernavigation : Konzeption und prototypische Implementierung eines smartphonebasierten Fußgängernavigationssystems / The use of augmented reality for pedestrian navigation : design and prototypical implementation of a smartphone-based pedestrian navigation system

Kluge, Mario January 2012 (has links)
Fußverkehr findet im gesamten öffentlichen Raum statt und ermöglicht die lückenlose Verbindung von Tür zu Tür. Jeder Mensch steht vor Beginn einer Fortbewegung vor den Fragen „Wo bin ich?“, „Wo liegt mein Ziel?“ und „Wie komme ich dahin?“. Ein Großteil der auf dem Markt befindlichen Navigationssysteme für Fußgänger stellen reduzierte Varianten aus Fahrzeugen dar und basieren auf 2D- Kartendarstellungen oder bilden die Realität als dreidimensionales Modell ab. Navigationsprobleme entstehen dann, wenn es dem Nutzer nicht gelingt, die Information aus der Anweisung auf die Wirklichkeit zu beziehen und umzusetzen. Ein möglicher Grund dafür liegt in der Visualisierung der Navigationsanweisung. Die räumliche Wahrnehmung des Menschen erfolgt ausgehend von einem bestimmten Betrachtungsstandpunkt und bringt die Lage von Objekten und deren Beziehung zueinander zum Ausdruck. Der Einsatz von Augmented Reality (erweiterte Realität) entspricht dem Erscheinungsbild der menschlichen Wahrnehmung und ist für Menschen eine natürliche und zugleich vertraute Ansichtsform. Im Unterschied zu kartographischer Visualisierung wird die Umwelt mittels Augmented Reality nicht modelliert, sondern realitätsgetreu abgebildet und ergänzt. Das Ziel dieser Arbeit ist ein Navigationsverfahren, das der natürlichen Fort-bewegung und Sichtweise von Fußgängern gerecht wird. Das Konzept basiert auf dem Einsatz einer Kombination aus Realität und virtueller Realität zu einer erweiterten Ansicht. Da keine Darstellungsform als die Route selbst besser geeignet ist, um einen Routenverlauf zu beschreiben, wird die Realität durch eine virtuelle Route erweitert. Die perspektivische Anpassung der Routendarstellung erfordert die sensorische Erfassung der Position und Lage des Betrachtungsstandpunktes. Das der Navigation zu Grunde liegende Datenmodell bleibt dem Betrachter dabei verborgen und ist nur in Form der erweiterten Realität sichtbar. Der im Rahmen dieser Arbeit entwickelte Prototyp trägt die Bezeichnung RealityView. Die Basis bildet ein freies und quelloffenes Navigationssystem, das für die Fußgängernavigation modular erweitert wurde. Das Ergebnis ist ein smartphonebasierter Navigationsprototyp, in dem die Ansichtsform einer zweidimensionalen Bildschirmkarte im Grundriss und die Darstellung einer erweiterten Realität im Aufriss kombiniert werden. Die Evaluation des Prototyps bestätigt die Hypothese, dass der Einsatz von Augmented Reality für die Navigation von Fußgängern möglich ist und von der Nutzergruppe akzeptiert wird. Darüber hinaus bescheinigen Wissenschaftler im Rahmen von Experten-interviews den konzeptionellen Ansatz und die prototypische Umsetzung des RealityView. Die Auswertung einer Eye-Tracking-Pilotstudie erbrachte den Nachweis, dass Fußgänger die Navigationsanweisung auf markante Objekte der Umwelt beziehen, deren Auswahl durch den Einsatz von Augmented Reality begünstigt wird. / Pedestrian traffic takes place in public spaces and provides a seamless connection from door to door. Right before the start of a movement, every human being faces the following questions "Where am I?", "What is my goal?" and "How do I get there?". Existing navigation systems for pedestrians are based on 2D map representations or depict reality as a three-dimensional model. As a result, the majority of the systems on the market for pedestrians are smaller versions of vehicle navigation systems. Navigation problems can occur if the user is unable to relate the information of an instruction to reality and cannot implement it. One possible reason for this is the visualization of the navigation instruction. Peoples spatial perception takes place from their own perspective and shows how objects are positioned and how they are related to each other. The use of Augmented Reality corresponds to the appearance of human perception, and this is a natural and yet familiar view. Compared to cartographic visualization techniques reality is not modeled but mapped realistically and refers to the environment. The concept of this thesis is directly linked to the current state of research and examines the use of a simple method and target group-oriented representation, which meets the natural movement of pedestrians. Its central focus is the combination of reality and virtual reality to a common view. This view will be extended by a virtual route representation, which follows the route course in reality. No other form of representation is better suited to explain the course of a route than the route itself. The perspective adjustment and the calculation of the virtual image scene require a data model, which remains hidden from the viewer and only appears in form of a virtual route. The navigation prototype, which is developed in this study, is based on Augmented Reality and is called RealityView. Its base is a free and open source navigation platform, which was expanded modularly into a pedestrian navigation system. The result is a smartphone-based navigation prototype, which combines the two forms of a two-dimensional screen map in plan with the illustration of an Augmented Reality in elevation. The validation of the prototype confirms the hypothesis that the use of Augmented Reality for pedestrian navigation is possible and is also accepted by the user group. In addition, in interviews with experts scientists have confirmed the conceptual approach and the implementation of the RealityView-prototype. The evaluation of an eye-tracking pilot study proved that the use of Augmented Reality favors the selection of prominent objects in the environment.
7

Estimation continue de la pose d'un équipement tenu en main par fusion des données visio-inertielles pour les applications de navigation piétonne en milieux urbains / Continuous pose estimation of handheld device by fusion of visio-inertial data for pedestrian navigation applications in urban environments

Antigny, Nicolas 18 October 2018 (has links)
Pour assister la navigation piétonne dans les espaces urbains et intérieurs, une estimation précise de la pose (i.e. la position 3D et l'orientation3D) d'un équipement tenu en main constitue un point essentiel dans le développement d'outils d'aide à la mobilité (e.g. applications de réalité augmentée). Dans l'hypothèse où le piéton n'est équipé que d'appareils grand public, l'estimation de la pose est limitée à l'utilisation de capteurs à faible coût intégrés dans ces derniers (i.e. un récepteur GNSS, une unité de mesure inertielle et magnétique et une caméra monoculaire). De plus, les espaces urbains et intérieurs, comprenant des bâtiments proches et des éléments ferromagnétiques, constituent des zones difficiles pour la localisation et l'estimation de la pose lors de grands déplacements piétons.Cependant, le développement récent et la mise à disposition d'informations contenues dans des Systèmes d'Information Géographiques 3D constituent une nouvelle source de données exploitable pour la localisation et l'estimation de la pose. Pour relever ces défis, cette thèse propose différentes solutions pour améliorer la localisation et l'estimation de la pose des équipements tenus en main par le piéton lors de ses déplacements en espaces urbains et intérieurs. Les solutions proposées intègrent l'estimation de l'attitude basée inertielle et magnétique, l'odométrie visuelle monoculaire mise à l'échelle grâce à l'estimation des déplacements du piéton, l'estimation absolue de la pose basée sur la reconnaissance d'objets SIG 3D parfaitement connus et la mise à jour en position de la navigation à l'estime du piéton.Toutes ces solutions s'intègrent dans un processus de fusion permettant d'améliorer la précision de la localisation et d'estimer en continu une pose qualifiée de l'appareil tenu en main.Cette qualification est nécessaire à la mise en place d'un affichage en réalité augmentée sur site. Pour évaluer les solutions proposées, des données expérimentales ont été recueillies au cours de déplacements piétons dans un espace urbain avec des objets de référence et des passages intérieurs. / To support pedestrian navigation in urban and indoor spaces, an accurate pose estimate (i.e. 3Dposition and 3D orientation) of an equipment held inhand constitutes an essential point in the development of mobility assistance tools (e.g.Augmented Reality applications). On the assumption that the pedestrian is only equipped with general public devices, the pose estimation is restricted to the use of low-cost sensors embedded in the latter (i.e. an Inertial and Magnetic Measurement Unit and a monocular camera). In addition, urban and indoor spaces, comprising closely-spaced buildings and ferromagnetic elements,constitute challenging areas for localization and sensor pose estimation during large pedestrian displacements.However, the recent development and provision of data contained in 3D Geographical Information System constitutes a new wealth of data usable for localization and pose estimation.To address these challenges, this thesis proposes solutions to improve pedestrian localization and hand-held device pose estimation in urban and indoor spaces. The proposed solutions integrate inertial and magnetic-based attitude estimation, monocular Visual Odometry with pedestrian motion estimation for scale estimation, 3D GIS known object recognition-based absolute pose estimation and Pedestrian Dead-Reckoning updates. All these solutions are fused to improve accuracy and to continuously estimate a qualified pose of the handheld device. This qualification is required tovalidate an on-site augmented reality display. To assess the proposed solutions, experimental data has been collected during pedestrian walks in an urban space with sparse known objects and indoors passages.
8

Multimodale Annotation geographischer Daten zur personalisierten Fußgängernavigation

Völkel, Thorsten 24 April 2009 (has links) (PDF)
Mobilitätseingeschränkte Fußgänger, wie etwa Rollstuhlfahrer, blinde und sehbehinderte Menschen oder Senioren, stellen besondere Anforderungen an die Berechnung geeigneter Routen. Die kürzeste Route ist nicht immer die am besten geeignete. In dieser Arbeit wird das Verfahren der multimodalen Annotation entwickelt, welches die Erweiterung der geographischen Basisdaten durch die Benutzer selbst erlaubt. Auf Basis der durch das Verfahren gewonnenen Daten werden Konzepte zu personalisierten Routenberechnung auf Grundlage der individuellen Anforderungen der Benutzer entwickelt. Das beschriebene Verfahren wurde erfolgreich mit insgesamt 35 Benutzern evaluiert und bildet somit die Grundlage für weiterführende Arbeiten in diesem Bereich. / Mobility impaired pedestrians such as wheelchair users, blind and visually impaired, or elderly people impose specific requirements upon the calculation of appropriate routes. The shortest path might not be the best. Within this thesis, the concept of multimodal annotation is developed. The concept allows for extension of the geographical base data by users. Further concepts are developed allowing for the application of the acquired data for the calculation of personalized routes based on the requirements of the individual user. The concept of multimodal annotation was successfully evaluated incorporating 35 users and may be used as the base for further research in the area.
9

The Potential for Augmented Reality to Bring Balance betweenthe Ease of Pedestrian Navigation and the Acquisition of Spatial Knowledge

Wen, James January 2014 (has links)
Being completely lost in an unfamiliar environment can be inconvenient, stressful and, at times, even dangerous. Maps are the traditional tools used for guidance but many people find maps difficult to use. In recent years, new tools like outdoor Augmented Reality (AR) have become available which allow virtual navigation cues to be directly overlaid on the real world, potentially overcoming the limitations of maps. However, it has been hypothesized that lower effort invested in processing navigation guidance may lead to diminished spatial knowledge (SK) thereby making users of such navigation tools far more vulnerable to getting lost should the tools fail for any reason. This thesis explores the research question of how AR and maps compare as tools for pedestrian navigation guidance as well as for SK acquisition and if there is a potential for AR tools be developed that would balance the two. We present a series of studies to better understand the consequences of using AR in a pedestrian navigation tool. The first two studies compared time-on-task performance and user preferences for AR and Map navigation interfaces on an outdoor navigation task. The results were not aligned with expectations, which led us to build a controlled testing environment for comparing AR and map navigation. Using this simulated setting, our third study verified the assumption that AR can indeed result in more efficient navigation performance and it supported the hypothesis that this would come at the cost of weaker SK. In our fourth study, we used a dual task design to compare the relative cognitive resources required by map and AR interfaces. The quantitative data collected indicated that users could potentially accept additional workload designed to improve SK without incurring significantly more effort. Our fifth and final study explored an interface with additional AR cues that could potentially balance navigation guidance with SK acquisition. The contributions of this thesis include insights into performance issues relating to AR, a classification of user types based on navigation tool usage behavior, a testbed for simulating perfect AR tracking in a virtual setting, objective measures for determining route knowledge, the capacity that pedestrian navigation tool users may have for performing additional tasks, and guidelines that would be helpful in the design of pedestrian navigation tools.
10

Multimodale Annotation geographischer Daten zur personalisierten Fußgängernavigation

Völkel, Thorsten 15 April 2009 (has links)
Mobilitätseingeschränkte Fußgänger, wie etwa Rollstuhlfahrer, blinde und sehbehinderte Menschen oder Senioren, stellen besondere Anforderungen an die Berechnung geeigneter Routen. Die kürzeste Route ist nicht immer die am besten geeignete. In dieser Arbeit wird das Verfahren der multimodalen Annotation entwickelt, welches die Erweiterung der geographischen Basisdaten durch die Benutzer selbst erlaubt. Auf Basis der durch das Verfahren gewonnenen Daten werden Konzepte zu personalisierten Routenberechnung auf Grundlage der individuellen Anforderungen der Benutzer entwickelt. Das beschriebene Verfahren wurde erfolgreich mit insgesamt 35 Benutzern evaluiert und bildet somit die Grundlage für weiterführende Arbeiten in diesem Bereich. / Mobility impaired pedestrians such as wheelchair users, blind and visually impaired, or elderly people impose specific requirements upon the calculation of appropriate routes. The shortest path might not be the best. Within this thesis, the concept of multimodal annotation is developed. The concept allows for extension of the geographical base data by users. Further concepts are developed allowing for the application of the acquired data for the calculation of personalized routes based on the requirements of the individual user. The concept of multimodal annotation was successfully evaluated incorporating 35 users and may be used as the base for further research in the area.

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