Dissertations / Theses on the topic 'Visual guidance systems'

ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California
This paper describes the concept of wide-angle coverage optical vision system integrated with guidance support of microwave or acoustical imaging arrays. The objective is to provide the capability of effective high-resolution full-view monitoring and sensing. The optical component, formed by a multi-camera array, is responsible for the main interface with human users. The acoustical and microwave arrays are integrated, allowing the system to function in the event-triggered modality for optimal efficiency. In this paper, the arrays discussed are in circular configurations. With minor modification, the system can also function with linear array configurations.

The elderly citizen’s health care need some radical changes and improvements to alleviate the situation where the quality of service must be enhanced without overburdening the caregivers under the weighty workload. Much of research is done and many researchers all around the world emphasize the importance of assistive technologies. Current technological advancements in communication allow us to build systems which could be useful tools for the caregivers and allow the elderly to live more autonomous and active life. Offering stimulus to the elderly to experience with the technology could lessen the feel of social isolation and ameliorate the quality of service significantly. Shrinking electronics, mobiles and sensors do not bound the use only in homes or facilities, but allow the use in many different environments. While using technology of this kind, the caregivers could give guidance or follow the health status of a mobile elderly citizen in remote fashion and give help if needed. This thesis is also immersing in the matter by producing a Visual Guidance system that utilizes current mobile technology, actuators, sensors and uses a virtual reality as a communication medium between the caregivers and elderly citizens. The system consists of two different parts combined together to form a real-time communication system between caregivers and elderly citizen. The system uses Android smart phone’s built-in sensors to track the movement of the elderly. Those sensors are location based sensors such as GPS and acceleration and magnetometer sensors. This system provides an open map view of the world where the elderly citizen move. Also to improve the communication between the elderly and caregiver, video and audio communication has been used as one of our research aims. The caregiver can remotely use the smart phone to open video and audio communication with the elderly if needed. The system has been integrated with indicator base smart glasses so that when the elderly citizen are on the move, the caregiver can give directional advices on where and when to go. The authors used integration testing to evaluate the system and comparing the current system functions with the requirements of the system. Also the authors made sure that the delay with communication was small enough so it would be safe for the caregivers to communicate with the elderly citizen. For future work we suggested various actions such as integrating indicator based glasses with the Pupil Pro glasses, finding the most appropriate security solutions for the system and testing the system with real-life caregivers and elderly citizen.

Due to the population aging phenomenon, the working-age population will decline in the future while the seniors’ quality of life can decline. A lot of research has been done and many of researchers figure out modern ICT and mobile technology needs to shoulder more responsibility in elderly care. The benefit of science and technology should be brought to senior citizens’ life. Moreover, the smartphone ownership rate has been increasing in recent years, espe- cially the percentage of Android phone ownership. Because elders will take smart- phone everywhere, installing an application in senior citizen’s Android phone is a good way to track their movements. The caregivers could give guidance remotely to elders based on their location and surrounding environment scene by using mobile technology of this kind. The multi user support for senior citizen visual guidance system consists of five components: Android phone, Pupil headset, Indicator-based Glasses, OldBirds and web server part. The system uses the Pupil headset to capture senior citizen’s font view and transfer it to OldBirds part which is controlled by caregivers. Furthermore, the Indicator-based glasses are used to show the guidance orders given by remotely caregivers. The web server part is transfer station between Android phone and OldBirds part. Google Cloud Messaging service has already been integrated into this system so that caregivers can directly give guidance orders to senior citizens about when and where to go. For future work I suggest, from the hardware perspective, to connect Pupil headset’s world camera and eye camera together by a USB hub. Furthermore, I recommend to combine Pupil headset and Indicator-based glasses together to remove the need for Bluetooth connection.

The ability to gather and process information regarding the condition of forest fires is essential to cost-effective, safe, and efficient fire fighting. Advances in sensory and autopilot technology have made miniature unmanned aerial systems (UASs) an important tool in the acquisition of information. This thesis addresses some of the challenges faced when employing UASs for forest-fire perimeter surveillance; namely, perimeter tracking, cooperative perimeter surveillance, and path planning. Solutions to the first two issues are presented and a method for understanding path planning within the context of a forest-fire environment is demonstrated. Both simulation and hardware results are provided for each solution.

Mestrado em Engenharia de Automação Industrial
The industrial automation has made its way in responding to the growing market’s needs. Companies that wish to keep up with the competition have a common goal: improve the product’s quality while reducing manufacturing costs and time. In the last decade, the autonomous guided vehicles (AGV) have gained expression due to the fact that they are capable of responding this the last mentioned necessity. The context of the current dissertation is inserted in the development of this thematic through the recovery of an equipment with industrial scale applications. The main goal is centered in the Robuter II platform’s retrofitting. For that, it is intended to replace the old control part by a modern solution that allows the integration of different modules based on a ROS distributed architecture. A detailed analysis of the existing platform was made in order to redo all the electrical installation, as well as to setup all of the used equipment. In the end, a vehicle capable of navigating, both manual and autonomously, was achieved. The vehicle can be operated manually (via remote control) and as a proof of concept, autonomous navigation was carried out through a simple artificial vision algorithm. It was also verified the versatility of the developed solution by integrating different equipment and designed code in a simple way. This document describes generally the project where all the different steps are identified, as well as all the work developed until the present moment. Furthermore, the guidelines to follow in order to achieve the proposed goals, is presented. Finally, navigation experimental results and the integration of different works on the platform are presented.
A automação industrial é uma parte fundamental para responder às crescentes necessidades do mercado. As empresas que desejam estar a par da competição, têm todas uma premissa em comum — melhorar a qualidade do produto, reduzindo custos e tempo de fabrico. Na última década, os veículos autonomamente guiados (AGV) têm ganho expressão devido ao facto de serem capazes de responder a esta última necessidade. O contexto da presente dissertação insere-se no desenvolvimento desta temática através da recuperação de um equipamento com aplicações à escala industrial. O objetivo principal passa por fazer o retrofitting da plataforma Robuter II, que se encontra obsoleta. Para isso, pretende-se substituir toda a parte de controlo por uma solução mais atual que permita a integração de diferentes módulos com base numa arquitetura distribuída baseada em ROS. Foi então necessário proceder a uma análise detalhada da plataforma existente para refazer toda a instalação elétrica da mesma, bem como proceder à instalação de diversos equipamentos. No final, obteve-se um veículo capaz de navegar de forma manual (com controlo remoto) e foi ainda realizada uma prova de conceito de navegação autónoma através da realização de um algoritmo simples de visão artificial. Foi ainda verificada a versatilidade suficiente para integrar diferentes equipamentos e código desenvolvido de forma simples. Neste documento é feita uma descrição geral do projeto onde são identificadas as várias etapas do mesmo e o trabalho desenvolvido até ao momento. Para além disso, é apresentada a forma como se irá proceder para a implementação das metas propostas. Por último, são apresentados resultados experimentais de navegação e integração de outros trabalhos na plataforma.

A smart phone camera based indoor guidance system to aid the visually impaired is presented. Most proposed systems for aiding the visually impaired with indoor navigation are not feasible for widespread use due to cost, usability, or portability. We use a smart phone vision based system to create an indoor guidance system that is simple, accessible, inexpensive, and discrete to aid the visually impaired to navigate unfamiliar environments such as public buildings. The system consists of a smart phone and a server. The smart phone transmits pictures of the user's location to the server. The server processes the images and matches them to a database of stored images of the building. After matching features, the location and orientation of the person is calculated using 3D location correspondence data stored for features of each image. Positional information is then transmitted back to the smart phone and communicated to the user via text-to-speech. This thesis focuses on developing the vision technology for this unique application rather than building the complete system. Experimental results demonstrate the ability of the system to quickly and accurately determine the pose of the user in a university building.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo desta pesquisa é avaliar representações cartográficas para manutenção na rota, em um Mapa Visual Dinâmico de Sistema de Navegação e Guia de Rota em Automóvel (SNGRA), por meio das análises de demanda visual, preferência subjetiva e erro navegacional. Os pontos de referência e os sinais de direção de trânsito são elementos de informação importantes que auxiliam os motoristas nas tarefas de manutenção na rota. A tese central é que o Mapa Visual Dinâmico de um SNGRA pode apresentar baixa demanda visual, alta preferência subjetiva e pouco erro navegacional quando se combina representação cartográfica áudio-dinâmica com pontos de referência representados na perspectiva do motorista e representação de seta para indicar a direção da manobra. Os elementos de pontos de referência foram selecionados a partir das características da atratividade visual e cognitiva de um pequeno espaço urbano brasileiro e, principalmente, da rota de teste. As representações cartográficas foram produzidas com base em fatores humanos (cognição, percepção e atenção) e, testadas junto a um grupo de 28 motoristas. Utilizou-se a estatística não paramétrica para analisar os dados coletados nos testes de demanda visual. Os resultados indicam as representações cartográficas eficientes e eficazes para manutenção na rota, bem como apontam a relação da demanda visual com os fatores sexo, habilidade espacial e experiências com mapas. Este trabalho confirma os resultados de pesquisas anteriores de que os motoristas preferem mapas para navegação e guia de rota em automóvel porque querem conhecer sua localização e o contexto espacial, em relação às referências urbanas.
The aim of this research is to evaluate cartographic symbols for route following in a Dynamic Visual Map of a Car Navigation and Route Guidance System, taking into account visual demand, subjective preference and navigational error. Landmarks and traffic signs are information elements that help drivers when following a route. The central hypothesis is that Dynamic Visual Map could be more efficient and effective when combining audio-dynamic cartographic representation with landmarks in a driver's perspective view and arrow to indicate maneuver direction. The landmarks were selected from characteristics of visual and cognitive attractiveness from a town and, mainly of the test route. The cartographic symbols were produced based on human factors (cognition, perception and attention) and tested with 28 drivers. Non-parametric statistic was applied in order to analyze the collected data from visual demand test. The results indicate cartographic symbols efficient and effective for route following, as well as point out association between visual demand with sex, spatial abilities and experiences with maps factors. This work confirm previous research that the most of drivers prefer maps to navigation and route following in car, because they want know en-route where they are in relation to particular areas and landmarks.

Le travail présenté a comme objectif d'élucider la nature des mécanismes mis en jeu dans le développement du système visuel d'un mammifère, la souris, et plus particulièrement dans la formation des cartes topographiques de la rétine, qui sont des caractéristiques de base de ce système. Le guidage des axones rétiniens vers leurs cibles centrales repose sur la capacité du cône de croissance axonal à reconnaitre des indices positionnels dans son environnement ; ces mécanismes de croissance dirigée sont accompagnés de mécanismes permettant une sélection des projections appropriées.

Orientador: Mônica Modesta Santos Decanini
Banca: Vilma Mayumi Tachibana
Banca: Nilton Nobuhiro Imai
Banca: Claudia Robbi Slutter
Banca: Luciene Stamato Delazari
Resumo: O objetivo desta pesquisa é avaliar representações cartográficas para manutenção na rota, em um Mapa Visual Dinâmico de Sistema de Navegação e Guia de Rota em Automóvel (SNGRA), por meio das análises de demanda visual, preferência subjetiva e erro navegacional. Os pontos de referência e os sinais de direção de trânsito são elementos de informação importantes que auxiliam os motoristas nas tarefas de manutenção na rota. A tese central é que o Mapa Visual Dinâmico de um SNGRA pode apresentar baixa demanda visual, alta preferência subjetiva e pouco erro navegacional quando se combina representação cartográfica áudio-dinâmica com pontos de referência representados na perspectiva do motorista e representação de seta para indicar a direção da manobra. Os elementos de pontos de referência foram selecionados a partir das características da atratividade visual e cognitiva de um pequeno espaço urbano brasileiro e, principalmente, da rota de teste. As representações cartográficas foram produzidas com base em fatores humanos (cognição, percepção e atenção) e, testadas junto a um grupo de 28 motoristas. Utilizou-se a estatística não paramétrica para analisar os dados coletados nos testes de demanda visual. Os resultados indicam as representações cartográficas eficientes e eficazes para manutenção na rota, bem como apontam a relação da demanda visual com os fatores sexo, habilidade espacial e experiências com mapas. Este trabalho confirma os resultados de pesquisas anteriores de que os motoristas preferem mapas para navegação e guia de rota em automóvel porque querem conhecer sua localização e o contexto espacial, em relação às referências urbanas.
Abstract: The aim of this research is to evaluate cartographic symbols for route following in a Dynamic Visual Map of a Car Navigation and Route Guidance System, taking into account visual demand, subjective preference and navigational error. Landmarks and traffic signs are information elements that help drivers when following a route. The central hypothesis is that Dynamic Visual Map could be more efficient and effective when combining audio-dynamic cartographic representation with landmarks in a driver's perspective view and arrow to indicate maneuver direction. The landmarks were selected from characteristics of visual and cognitive attractiveness from a town and, mainly of the test route. The cartographic symbols were produced based on human factors (cognition, perception and attention) and tested with 28 drivers. Non-parametric statistic was applied in order to analyze the collected data from visual demand test. The results indicate cartographic symbols efficient and effective for route following, as well as point out association between visual demand with sex, spatial abilities and experiences with maps factors. This work confirm previous research that the most of drivers prefer maps to navigation and route following in car, because they want know en-route where they are in relation to particular areas and landmarks.
Doutor

[Truncated abstract] During development of the visual system, topographic connections between the retina and the superior colliculus are established using guidance molecules. The EphA family of tyrosine kinase receptors and their ephrin-A ligands are important for establishing topography between the temporo-nasal axis of the retina and the rostro-caudal axis of the superior colliculus. After injury to the visual system via unilateral optic nerve transection, adult mammalian retinal ganglion cells fail to regenerate axons spontaneously to their main visual centre, which in rodents, is the superior colliculus. The EphA5 gradient is down-regulated from a temporalhigh to nasallow gradient to a uniform low level in the few surviving retinal ganglion cells, but ephrin-A2 is upregulated back to a significant rostrallow to caudalhigh gradient in the superior colliculus, similar to that seen during development. In this thesis, a number of experiments have been undertaken to investigate further how EphA5 and ephrin-A2 are regulated after injury and how they may play a role once regeneration has been encouraged through surgical intervention. In the first study, targeted unilateral retinal laser lesions were used to ablate either dorso-nasal or ventro-temporal quadrants of the retina. ... Surviving and regenerating retinal ganglion cells in the retina, and axons in the optic nerve, were analysed. The data suggest that metallothionein-I/II increases axonal regeneration through the optic nerve injury site but, at the dose administered, had no neuroprotective effects on retinal ganglion cells. This thesis provides further insight into the response of guidance molecules to injury, and the potential of metallothionein-I/II as a neuroregenerative factor in the adult mammalian visual system. The regulation of both EphA5 and ephrin-A2 through transsynaptic connections may be a response common to other guidance molecules. Such connectivity now needs to be studied further to understand how it may impact on various treatments designed to increase re-connectivity after other brain injuries, including stroke. The ectopic expression of ephrin-A2 at the insertion site of a peripheral nerve graft in the superior colliculus, implicate this guidance molecule in the glial scar for the first time. Therefore, to overcome inhibition by the glial scar, axons must also overcome ephrin-A2 mediated inhibition, potentially by the addition of EphA5 fusion proteins. Metallothionein-I/II?s effect of increasing axonal regeneration through the optic nerve injury site suggests that it could be used to increase the number of regenerating axons reaching their target. Such strategies to increase the absolute number of regenerated axons should enable these axons to better use the EphA5 and ephrin-A2 topographic gradients to optimize regenerative success.

Le développement des systèmes de communication et de localisation et les progrès des dispositifs mobiles rendent possible la mise en œuvre de nouvelles applications et services, permettant l'accès à des informations temps réel et l'amélioration de l'intégration des personnes aveugles. Dans ce contexte, la thèse a contribué au développement d'un système d'information et de guidage destiné aux personnes aveugles dans les transports en commun. La thèse a porté sur deux aspects critiques de ce type de systèmes: la fiabilité de la transmission de données et la capacité à localiser et à guider l'utilisateur de manière robuste. Elle a d'autre part développé un environnement de simulation pour le prototypage et l'analyse du fonctionnement de l'application nomade ainsi que l'étude des aspects réseaux de communication mobile. Les travaux se sont appuyés sur les acquis des projets RAMPE et INFOMOVILLE
The development of communication and locating systems and the progress of mobile devices have made possible new applications and services, allowing access to real-time information and improving the integration of blind people. ln this context, the thesis has contributed to the development of an information and guidance system to be used by blind travellers in public transports. The work has focused on two critical aspects for this kind of systems: the reliability of data transmission and the ability of localizing and guiding the user in an efficient way. A simulation environment has also been developed that can be used for the prototyping and the analysis of the mobile application as well as for the study of communication over the wireless network. The thesis is based on the results of the RAMPE and INFOMOVILLE projects

Cette thèse propose de nouvelles commandes basées sur un retour visuel pour le guidage de drones. Elle considère à la fois des scénarios impliquant un seul ou plusieurs véhicules. Pour le cas du guidage d'un seul véhicule, de nouvelles approches d'asservissement visuel basées image (IBVS) sont proposées pour les drones de type avion (fixed-wing) et les drones de type VTOL (Vertical Take-Off and Landing) opérant en environnements urbains ou encombrés. Des tâches de navigation dans un environnement complexe avec des capacités d'évitement d'obstacle sont considérées. Il s'agit en particulier de l'atterrissage de drones de type fixed-wing sur une piste d'atterrissage et l'atterrissage de drones de type VTOL-UAV en incluant une stratégie d'évitement d'obstacle. L'originalité de l'étude réside dans l'exploitation directe de la centroïde de l'image du motif observé et du flux optique permettant ainsi d'éliminer la nécessité l'estimation de la position et la vitesse du drone. Pour le cas du contrôle de plusieurs véhicules en formation, de nouveaux contrôleurs à base de la mesure de direction entre véhicules sont également proposés pour des formations ayant une interaction topologique orientées ou non orientées. Le flux optique est également exploité dans certains cas afin d'éviter les collisions entre différents agents pendant l'évolution de la formation. Afin d'assouplir les conditions classiques requises par la théorie de la rigidité d'une formation à partir de l'information de direction et lever par la même occasion l'ambiguïté du facteur d'échelle causée par les mesures de directions, la notion de la persistance de l'excitation associée à la formation de référence est explorée. La méthodologie proposée est soutenue par des outils mathématiques rigoureux (impliquant des systèmes dynamiques non linéaires et analysés à l'aide de la théorie de Lyapunov afin de prouver formellement la stabilité asymptotique (ou exponentielle) du système, de garantir la robustesse et enfin d'assurer le bon fonctionnement du système en boucle fermée) et par des expériences réelles et/ou des résultats de simulation
This thesis proposes novel vision-based controllers for the guidance of Unmanned Aerial Vehicles (UAVs). It considers scenarios involving both single and multiple vehicles. For the case of a single-vehicle, novel Image-based visual servo control (IBVS) approaches are proposed for both fixed-wing and vertical take-off and landing (VTOL) UAVs operating in urban or congested environments. Navigation tasks in a complex environment with obstacle avoidance capabilities are considered. In particular, the landing of fixed-wing UAVs on an airstrip and the landing of VTOL-UAVs that includes an obstacle avoidance strategy are considered. The originality of the study lies in the direct exploitation of the centroid of the image of the observed pattern together with the optical flow, thereby eliminating the need to estimate the position and the velocity of the UAV.For multiple vehicles, novel bearing formation controllers are designed for formations under both directed and undirected interaction topologies. Optical flow is explored in the bearing formation control laws in order to achieve collision avoidance between different agents during the formation progression.In order to relax the classical conditions required by bearing rigidity theory and to lift the scale ambiguity caused by bearings, persistence of excitation of the desired bearing reference is explored. The proposed methodology is supported by rigorous mathematical tools (This involves nonlinear dynamical systems and analysis using Lyapunov theory to formally prove the asymptotic (or exponential) stability of the system, guarantee robustness, and finally ensure good performance of the closed-loop system). Further support is provided by real experiments and/or simulation results

Alors que la population mondiale vieillit et vit de plus en plus en zone urbaine, maintenir les capacités de mobilité piétonne des personnes âgées en ville est un enjeu majeur pour leur santé et leur autonomie. La marche est, en effet, un des modes principaux de déplacement des personnes âgées en ville. Cependant, les déclins perceptifs, cognitifs et moteurs liés à l'avancée en âge peuvent affecter considérablement cette activité quotidienne.La navigation piétonne, qui consiste à aller d'un point A à un point B, peut être particulièrement affectée par l’avancée en âge. Il s’agit d’un processus complexe, sollicitant de nombreuses fonctions perceptives et cognitives, afin de percevoir, analyser et intégrer un grand nombre d’informations pour se déplacer. Si les personnes âgées recourent le plus souvent aux cartes papier pour s’aider dans cette activité de navigation, ces supports sont peu adaptés, car ils mobilisent des informations allocentrées (en vue du dessus) difficiles à interpréter par les personnes âgées, et font fortement appel à l’attention visuelle, qui est nécessaire par ailleurs pour naviguer en toute sécurité.Des aides à la navigation technologiques (type GPS) pourraient permettre de lever certaines difficultés de mobilité avec l’âge, en fournissant des informations de guidage à travers plusieurs canaux sensoriels, et ce afin de limiter le partage attentionnel. Ces aides devraient également proposer une expérience utilisateur positive, afin de faciliter leur acceptation par une population âgée pas toujours à l’aise avec les technologies.Cette thèse en psychologie ergonomique s’intéresse à l’efficacité et à l’expérience utilisateur de plusieurs aides à la navigation technologiques mobilisant des instructions pas-à-pas égocentrées (en vue à la première personne) à travers les sens visuel, auditif et haptique pour la navigation piétonne des personnes âgées. Après avoir questionné les pratiques de mobilité piétonne et les différences existant entre personnes actives et retraitées (étude 1), nous avons comparé, lors d’une étude en environnement virtuel (étude 2), différentes instructions de guidage pas-à-pas faisant appel aux sens visuel (flèches incrustées sur simulateur), auditif (sons spatialisés par casque à conduction osseuse) et haptique (montre vibrante au poignet droit), ainsi que l’utilisation d’une carte papier. Nous avons pu mettre en valeur que des difficultés de navigation observées chez les participants âgés avec la carte pouvaient être compensées par le recours à un guidage par flèches visuelles ou sons spatialisés. Nous avons poursuivi ce travail par une étude en environnement naturel urbain (étude 3) au cours de laquelle des participants âgés ont été invités à parcourir des itinéraires avec leur aide habituelle (carte), un guidage visuel par flèches projetées sur des lunettes de réalité augmentée, un guidage auditif par sons spatialisés grâce à un casque à conduction osseuse, et un guidage vibro-visuel proposant flèches et vibrations par le biais d’une montre connectée. Les résultats obtenus par des observables et des entretiens indiquent que les lunettes de réalité augmentée paraissent cette fois-ci, en contexte naturel, et au contraire de l’étude 2 sur simulateur, moins adaptées que le casque à conduction osseuse et que la montre connectée, ces deux derniers dispositifs montrant des résultats très positifs. La perceptibilité des instructions, leur interprétation en contexte de navigation, et le confort des participants sont grandement dépendants du dispositif technique utilisé.Dans une dernière étude, nous avons investigué les facteurs susceptibles de favoriser l’acceptabilité d’aides à la navigation qui ne sont pas disponibles sur le marché mais pourraient exister demain (ex. lentilles de réalité augmentée, vêtements vibrants, etc.). Nous proposons, en conclusion, plusieurs recommandations utiles à la conception d’aides à la navigation adaptées aux besoins et aux attentes des piétons âgés
As worldwide population is ageing and concentrating in cities, maintaining older people's pedestrian mobility in urban areas has become a key issue for their health and autonomy. Walking is, indeed, one of the most frequent transportation mode used by older people in cities. But age-related perceptual, cognitive and physical declines could negatively impact this daily activity.Pedestrian navigation, which consists in moving from a point A to a point B, could be particularly affected when advancing in age. It involves complex cognitive and perceptual processes to perceive and understand a multiplicity of information required to reach destination. Older people tend to use paper maps to help them finding their way while navigating. But maps are not suitable for older pedestrians because they provide allocentric information (viewed from the top) which is difficult to understand when advancing in age and requires a lot of visual attention which is also needed to navigate safely. Technological pedestrian navigation aids (such as GPS systems) may help older people to navigate by providing them guidance messages via various sensory modalities in order to limit attention sharing. Those aids should also be related to a positive user experience to facilitate their acceptation among older people who feel not necessarily comfortable with technologies. This thesis in ergonomic psychology focuses on how older people perceive and experience various technological pedestrian navigation aids, providing them with visual, auditory and haptic egocentric turn-by-turn guidance messages. We firstly investigated the reasons why people use pedestrian mobility in their daily activities and the differences existing between retired and non-retired people (study 1). We then compared some step-by-step guidance messages to a paper map in a virtual environment (study 2). We used visual messages (arrows inlayed on the screen of the simulator), auditory messages (spatialized sounds provided by a bone-conduction headset) and haptic messages (vibrating watch around the right wrist) and highlighted that the increased difficulties faced by older people to find their way with a map could be compensated using visual arrows or spatialized sound. We then continued this work in a real urban environment (study 3). People were asked to navigate some routes with their own navigation aid (usually a map), or arrows inlayed in their field of view thanks to augmented-reality glasses, or spatialized sounds provided by a bone-conduction headset, or arrows displayed on a smartwatch that vibrated to announce that a visual message was incoming. Augmented-reality glasses were less suitable for older pedestrians than bone-conduction headset and smartwatch in the natural environment, which was different from the results observed in virtual environment. Results from the interviews showed that the perceptibility of the messages, the way people interpreted them in the environment, and the comfort people felt was highly conditioned by the device used. We finally investigated which UX dimensions cloud foster or limit the acceptability of some sensory navigation aids that do not exist yet but could exist in a near future (augmented-reality lens, vibrating clothes etc.).As a conclusion, we provide the reader with recommendations for designing navigation aids that are adapted to older pedestrians’ needs and expectations

Pour se localiser en ville, la majorité des solutions commercialisées se base sur les systèmes GPS. Même si ces systèmes offrent une précision suffisante hors agglomération, celle-ci se dégradent considérablement en villes à cause des phénomènes connus sous le nom du canyon urbain (i.e. réflexion du signal GPS sur les façades des bâtiments). Pour pallier ce problème, les solutions basées sur un SLAM visuel (Simultaneous Localization And Mapping) semblent une alternative prometteuse. En plus de l'estimation des six degrés de liberté de la caméra mobile, il fournit une carte 3D de la scène observée. Toutefois, la localisation assurée par le SLAM visuel n'est pas géo-référencée et présente souvent des dérives (e.g. mauvaise estimation du facteur d'échelle, accumulation des erreurs). Pour faire face à ces limitations et afin de proposer une solution facile à déployer, nous avons étudié la possibilité d'intégrer au SLAM des informations supplémentaires qui pourraient contraindre l'ensemble de la reconstruction fournie. Ces dernières doivent alors être peu couteuses et disponibles en milieux urbains denses et péri-urbains. C'est pour cette raison que nous avons choisi d'exploiter les contraintes fournies par un GPS standard et celles apportées par des modèles issus des Systèmes d'Information Géographique, plus précisément : des modèles 3D des bâtiments et des modèles d'élévation de terrain. La principale contribution de ces travaux réside en l'intégration de ces contraintes au sein de l'ajustement de faisceaux (i.e. processus d'optimisation du SLAM). Ceci n'est pas trivial étant donné que combiner des contraintes agissant sur la trajectoire de la caméra et la reconstruction 3D peut entrainer des problèmes de convergences, en particulier lorsque les informations exploitées ont des incertitudes variées, voire même des données biaisées ou aberrantes (e.g. Pour les mesures du GPS). Différentes solutions Larnaout et al. (2012, 2013a,b,c) permettant de combiner plusieurs de ces contraintes simultanément tout en limitant les problèmes de convergence ont été développées. Les solutions proposées ont été validées sur des séquences de synthèse et d'autres réelles de plusieurs kilomètres enregistrées dans des conditions de circulation normale. Les résultats obtenus montrent que la précision atteinte au niveau de l'estimation des six degrés de liberté de la caméra permet d'assurer des nouvelles applications d'aide à la navigation par le biais de la Réalité Augmentée. En plus de leur précision, nos approches ont l'avantage d'être rapides, peu couteuses et faciles à déployer (ne nécessitant pas un matériel sophistiqué).

Les systèmes d'aide à la conduite et les travaux concernant le véhicule autonome ont atteint une certaine maturité durant ces dernières aimées grâce à l'utilisation de technologies avancées. Une étape fondamentale pour ces systèmes porte sur l'estimation du mouvement et de la structure de l'environnement (Structure From Motion) pour accomplir plusieurs tâches, notamment la détection d'obstacles et de marquage routier, la localisation et la cartographie. Pour estimer leurs mouvements, de tels systèmes utilisent des capteurs relativement chers. Pour être commercialisés à grande échelle, il est alors nécessaire de développer des applications avec des dispositifs bas coûts. Dans cette optique, les systèmes de vision se révèlent une bonne alternative. Une nouvelle méthode basée sur des approches 2D/2D à partir d'un réseau de caméras asynchrones est présentée afin d'obtenir le déplacement et la structure 3D à l'échelle absolue en prenant soin d'estimer les facteurs d'échelle. La méthode proposée, appelée méthode des triangles, se base sur l'utilisation de trois images formant un triangle : deux images provenant de la même caméra et une image provenant d'une caméra voisine. L'algorithme admet trois hypothèses: les caméras partagent des champs de vue communs (deux à deux), la trajectoire entre deux images consécutives provenant d'une même caméra est approximée par un segment linéaire et les caméras sont calibrées. La connaissance de la calibration extrinsèque entre deux caméras combinée avec l'hypothèse de mouvement rectiligne du système, permet d'estimer les facteurs d'échelle absolue. La méthode proposée est précise et robuste pour les trajectoires rectilignes et présente des résultats satisfaisants pour les virages. Pour affiner l'estimation initiale, certaines erreurs dues aux imprécisions dans l'estimation des facteurs d'échelle sont améliorées par une méthode d'optimisation : un ajustement de faisceaux local appliqué uniquement sur les facteurs d'échelle absolue et sur les points 3D. L'approche présentée est validée sur des séquences de scènes routières réelles et évaluée par rapport à la vérité terrain obtenue par un GPS différentiel. Une application fondamentale dans les domaines d'aide à la conduite et de la conduite automatisée est la détection de la route et d'obstacles. Pour un système asynchrone, une première approche pour traiter cette application est présentée en se basant sur des cartes de disparité éparses
Driver assistance systems and autonomous vehicles have reached a certain maturity in recent years through the use of advanced technologies. A fundamental step for these systems is the motion and the structure estimation (Structure From Motion) that accomplish several tasks, including the detection of obstacles and road marking, localisation and mapping. To estimate their movements, such systems use relatively expensive sensors. In order to market such systems on a large scale, it is necessary to develop applications with low cost devices. In this context, vision systems is a good alternative. A new method based on 2D/2D approaches from an asynchronous multi-camera network is presented to obtain the motion and the 3D structure at the absolute scale, focusing on estimating the scale factors. The proposed method, called Triangle Method, is based on the use of three images forming a. triangle shape: two images from the same camera and an image from a neighboring camera. The algorithrn has three assumptions: the cameras share common fields of view (two by two), the path between two consecutive images from a single camera is approximated by a line segment, and the cameras are calibrated. The extrinsic calibration between two cameras combined with the assumption of rectilinear motion of the system allows to estimate the absolute scale factors. The proposed method is accurate and robust for straight trajectories and present satisfactory results for curve trajectories. To refine the initial estimation, some en-ors due to the inaccuracies of the scale estimation are improved by an optimization method: a local bundle adjustment applied only on the absolute scale factors and the 3D points. The presented approach is validated on sequences of real road scenes, and evaluated with respect to the ground truth obtained through a differential GPS. Finally, another fundamental application in the fields of driver assistance and automated driving is road and obstacles detection. A method is presented for an asynchronous system based on sparse disparity maps

碩士
國立交通大學
機械工程系
89
As the speed of computer becomes faster, the application of the machine vision is also broadened. In this work, we apply the machine vision to the automatically visual guidance of the intelligent vehicle. By the image process and the camera calibration, we can find the curvature of the road and provide this information to the vehicle dynamic system. Thus the vehicle can trace the road automatically. Since the data of the image is too large and image process takes much time. So it is hard to apply the machine vision to the high-speed control system. In order to shorten the time of image process, we use the control theorem, combine the road model and the vehicle model to predict the position of the feature object on the image. In this way, it makes possible to apply the machine vision to the high-speed control system.

碩士
大同大學
機械工程學系(所)
99
This paper presents a PC based vision system and control scheme for guiding the autonomous robot in unknown environment. By using Kinect from Microsoft newest product, the vision system measures the three dimensional relative distance and builds a map between the robot and surrounding object. The robot includes a MCU (Microchip PIC18F4520) as control unit and a Bluetooth as wireless communication module. According to the map, system can control and guide a wireless robot moving to command position and avoiding obstacles in Kinect's visible area. With this system, user can set a goal on the map, then the robot will be guided to move to the goal.

碩士
大同大學
機械工程學系(所)
93
With the speed up of computer efficiency and bandwidth of network, the digital consumer products have been incorporated among our life gradually. A visual guidance system with wireless control was proposed in this thesis to control an intelligent domestic vacuum（IDV）, which can developed the moving paths to clean a dusty area automatically. The histogram thresholding method and the manual decided threshold were used to isolate the image of IDV and T shape mark image （on the top of IDV）from the real time image. A shape center-calculating and shape-calculating algorithms were developed to calculate the position and the direction of intelligent domestic vacuum. There are two operation modes were developed in this study. When system operated under the manual guidance mode, user can set the moving path. On the other hand, the moving path was created automatically by the system in visual guidance mode. And the system will generate the guidance paths with proposed algorithm. Finally, the system drives the IDV automatically and compares its real position with the generated guidance paths until the mission finished.

碩士
國立臺灣科技大學
電子工程系
105
There are 285 million people with visually impairment in the world, helping them walking free on a familiar/unfamiliar place is an important issue nowadays. This thesis presents a wearable guidance system on a pair of wearable glasses with a mobile phone for people with visual impairment. The proposed system is based on a special designed voice-marker recognition. Because people with visual impairment have difficulty searching normal 2-D barcode based markers in environments, this thesis proposed a custom color marker which is detectable in 15m maximum when its size is 400 〖cm〗^2 and containing voice information inside. Users can obtain the audio message of current location information though the system without any network connection or a database. The marker recognition can be processed in real-time on most quad-core mobile phones. In addition, to ensure safe walk experiences for people with visual impairment, multiple micro ultrasonic sensors are used to achieve obstacles detection for low power. The function of positioning and obstacles detection can work standalone or in parallel. In order to achieve low power system architecture and avoid overloading, glasses are only responsible for obtaining and transmitting data including image sequence and ultrasonic sensors values. The mobile phone processes these data to get the location and detect obstacles. The proposed system could help people with visual impairment have better experience in many environments such as bus stations or department stores, and arrive at their destination in a safe way without other’s assistance.

碩士
國立中山大學
機械與機電工程學系研究所
107
Visually impaired people always experience inconvenience to manage many issues in their daily life. Crossing the road without tactile paving becomes a great challenge to the blind, who can only rely on the tactile stick. Based on this motivation, the thesis aims to develop a portable assistive guiding system using techniques of machine vision to allow the visually impaired people can always walk on the central area of the crosswalks while crossing the road. Both safety and autonomy of visually impaired people can therefore be improved. This research incorporates image processing approaches to locate the central position of the crosswalks even affected by occlusion of pedestrians and interference of shadow. In addition, statistical approaches are also applied to reduce the influence of fault detection. A vibration device is then employed to provide information of guidance for the visually impaired people. The experiments are divided into two groups, static and dynamic images, to examine performance of the proposed middle-line detection algorithm and guidance of vibration strategy. In order to consider all possible appearances of crosswalks in the image, four different conditions, head-on without occlusion, oblique without occlusion, head-on with occlusion, and oblique with occlusion, are studied. Finally, the presented assistive guiding system demonstrates promising performance to direct a healthy person with both eyes covered walking on the crosswalks to pass through a road in the real world.

Reactive oxygen species (ROS) are critical for maintaining cellular homeostasis and function when produced in physiological ranges. Important sources of cellular ROS include NADPH oxidases (Nox), which are evolutionarily conserved multi-subunit transmembrane proteins. Nox-mediated ROS regulate a variety of biological processes including stem cell proliferation and differentiation, calcium signaling, cell migration, and immunity. ROS participate in intracellular signaling by introducing post-translational modifications to proteins and thereby altering their functions. The central nervous system (CNS) expresses different Nox isoforms during both development and adulthood. There is now emerging evidence that Nox-derived ROS also control neuronal development and pathfinding. Our lab has recently shown that retinal ganglion cells (RGCs) from nox2 mutant zebrafish exhibit pathfinding errors. However, whether Nox could act downstream of receptors for axonal growth and guidance cues is presently unknown. To investigate this question, we conducted a detailed characterization of the zebrafish nox2 mutants that were previously established in our group. Abnormal axon projections were found throughout the CNS of the nox2 mutant zebrafish. Anterior commissural axons failed proper fasciculation, and aberrant axon projections were detected in the dorsal longitudinal fascicle of the spinal cord. We showed that the major brain regions are intact and that the early development of CNS is not significantly altered in nox2 mutants. Hence, the axonal deficits in nox2 mutants are not due to general developmental problems, and Nox2 plays a role in axonal pathfinding and targeting. Next, we investigated whether Nox2 could act downstream of slit2/Robo2-mediated guidance during RGC pathfinding. We found that slit2-mediated RGC growth cone collapse was abolished in nox2 mutants in vitro. Further, ROS biosensor imaging showed that slit2 treatment increased growth cone hydrogen peroxide levels via mechanisms through Nox2 activation. Finally, we investigated the possible relationship between slit2/Robo2 and Nox2 signaling in vivo. Astray/nox2 double heterozygous mutant larvae exhibited decreased tectal area as opposed to individual heterozygous mutants, suggesting both Nox2 and Robo2 are required for the establishment of retinotectal connections. Our results suggest that Nox2 is part of a signal transduction pathway downstream of slit2/Robo2 interaction regulating axonal guidance cell-autonomously in developing zebrafish retinal neurons.

Our work on RGMb demonstrates a clear and new role in the developing chick visual system. RGMb is expressed in distinct areas of the developing visual system: retinal ganglion cells (RGCs) of the retina, which are the only cells in the visual system that extend axons to the brain, as well as newly differentiated neuronal cells within the optic tectum (OT), the primary target of RGC axons. Knockdown of RGMb in RGCs at embryonic day 2 (E2) resulted in aberrant axon projection at E17, indicating that RGMb is required for axon development. Furthermore, knockdown of RGMb in the optic tectum at E5 resulted in disrupted cellular migration at E9, demonstrating that RGMb is involved in correct cell migration. Lastly, we demonstrated that RGMb binds to the Fibronectin III (3,4) domain of Neogenin, which provides a basis for determining the mechanism through which RGMb exerts its biological effects.

碩士
國立交通大學
電機資訊國際學程
101
Safe navigation in non-familiar outdoor environments is a challenging activity for the blind and vision-impaired (BVI) people. This work introduces a prototype of a cloud-based outdoor assistive navigation system (COANS) for BVI people. The main goal of the system is to provide easy street navigation and help to make outdoor walks in non-familiar environment less stressful. Hardware part from the user-side includes an android-base mobile phone and an external low-cost L1 GPS receiver to improve position accuracy. Applying the technique known as Real Time Kinematic (RTK) ameliorates the issue of the user position estimation. Interaction between the application and the user is based on voice commands (user-side) and voice notifications (system-side), together with the user-friendly “shaking” and “swiping” commands. The test scenarios for the system include traffic light status detection, zebra crossing path detection and a bench discovering within a short distance from the user.

碩士
國立高雄師範大學
資訊教育研究所
96
When a visually impaired person enters an unfamiliar indoor environment, he always needs a sighted person standing nearby for guidance; otherwise, he has to spend a long time exploring the environment himself. Even if he is in a familiar site, if objects in the site are moved or changed unexpectedly, he must explore the environment all over again. To address the above problems, we develop an indoor guidance system integrated with RFID devices. When the visually impaired people apply this system, they can quickly get the related information of the unfamiliar environment by the voice output of our system. With this system the visually impaired people can explore an indoor environment easily even without the guidance of normal people. Specifically, the purpose of this research is to solve problems such as location identification, searching objects near a target object, colliding with a barrier, and avoiding dangerous objects. These problems may occur when visually impaired people are in an unfamiliar environment. We take advantages of RFID(RFID，Radio Frequency Identification) technology to save/send identification data and access data repeatable. First, we stick RFID Tags onto objects in the environment for identification. The visually impaired people apply a mobile device such as PDA equipped with a RFID reader to get different information from this system. The basic process of our system is divided into four parts. First, the mobile device judges whether RFID Tags exist in the sensing area or not. Then the device sends the unique ID to the back-end server. According to different functions, the back-end server will produce different voice output data. Finally, the back-end server returns the voice output data to mobile device. Through the voice output information, visually impaired people can easily know the arrangement of the indoor environment.

碩士
朝陽科技大學
工業工程與管理系碩士班
96
Visually impaired people usually have met the problems in identifying the traffic signal and how to cross the street. These problems will make them failed to cross the intersection. The purpose of this study is to identify visually impaired people’s demand and build up a guidance system helping them cross the intersection safely. By using questionnaires from 218 subjects to understand requirements of visually impaired people crossing intersection, the most two requirements are lacking the signal of sound (61.0%) and unable to identify the traffic lamp signal (65.9%). A guidance system to cross intersections for the visually impaired was build up in the study. This guidance system includes two main parts: one is a mobility device carried and controlled by the user, the other is a device mounted on the pedestrian crossing light and commucated with users’ mobility device. The visually impaired people could obtain the vocal signal guidance when crossing the intersections. The experimental result from the visually impaired people showed that vocal signal guidance is more effective. The combination of both white cane and users’ mobility device at the same time, the mobility accuracy for the visually impaired people will be enhanced.

Durant le développement du système visuel, les cellules ganglionnaires de la rétine (CGRs) envoient des axones qui seront influencés par divers signaux guidant leur cône de croissance, permettant ainsi la navigation des axones vers leurs cibles terminales. Les endocannabinoïdes, des dérivés lipidiques activant les récepteurs aux cannabinoides (CB1 et CB2), sont présents de manière importante au cours du développement. Nous avons démontré que le récepteur CB2 est exprimé à différents points du tractus visuel durant le développement du hamster. L’injection d’agonistes et d’agonistes inverses pour le récepteur CB2 a modifié l’aire du cône de croissance et le nombre de filopodes présents à sa surface. De plus, l’injection d’un gradient d’agoniste du récepteur CB2 produit la répulsion du cône de croissance tandis qu’un analogue de l’AMPc (db-AMPc) produit son attraction. Les effets du récepteur CB2 sur le cône de croissance sont produits en modulant l’activité de la protéine kinase A(PKA), influençant la présence à la membrane cellulaire d’un récepteur à la nétrine-1 nommé Deleted in Colorectal Cancer (DCC). Notamment, pour que le récepteur CB2 puisse moduler le guidage du cône de croissance, la présence fonctionnelle du récepteur DCC est essentielle.. Suite à une injection intra-occulaire d’un agoniste inverse du récepteur CB2, nous avons remarqué une augmentation de la longueur des branches collatérales des axones rétiniens au niveau du LTN (noyau lateral terminal). Nous avons également remarqué une diminution de la ségrégation des projections ganglionnaires au niveau du dLGN, le noyau genouillé lateral dorsal, chez les animaux transgéniques cnr2-/-, ayant le gène codant pour le récepteur CB2 inactif. Nos données suggèrent l’implication des endocannabinoïdes et de leur récepteur CB2 dans la modulation des processus de navigation axonale et de ségrégation lors du développement du système visuel.
Retinal projection navigation towards their visual targets is regulated by guidance molecules and growth cone transduction mechanisms. Here, we show that cannabinoid receptor 2 (CB2R) is widely expressed throughout the visual pathway during development and in cultured retinal ganglion cells (RGCs) and cortical neurons. Both the number of filopodia and the surface area of the growth cone (GC) are modulated by CB2R activity in a PKA-dependant manner. Furthermore, DCC is required for CB2R induced morphological changes of the GC. CB2R agonists induce GC chemorepulsion. Treatments altering CB2R activity change retinal explants projections length. These effects are specific to CB2R as no changes were observed in cnr2 knockout mouse. A single intraocular injection of AM630 increases retinal projection branch length and aberrant projections were also observed. Moreover, we report defect in eye-specific segregation of retinal projections in the dLGN in cnr2-/- mice. These findings highlight the modulatory role of endocannabinoids and their CB2R during axon guidance.

An investigation of the individual perceptions of selected students, teachers, and parents toward the use of computer-assisted instruction (CAI) in a careers program was undertaken to provide information about the role CAI plays in the career education curriculum and other curricular areas utilizing CAI. A qualitative methodology was selected which utilized the informal conversational interview, allowing the researcher to be responsive to individual differences and situational changes to establish in-depth communication. Data analysis consisted of a constant comparative process approach, which allowed for analysis of data from different sources, within a data triangulation design across the three subject groups. The subjects were from a small rural school district and consisted of five high school students, six of their parents, and their teacher. As a result of the research, several significant factors about CAI, career programs, and computer usage were formed into the following hypothesis: 1) Students who have access to computers on a regular basis and are provided with training will be comfortable and enthusiastic about their use. 2) Computers are an essential information and communication tool whose access and use by students gives them an advantage in school and later in life. 3) Students feel the use of the computer for word processing and publishing is significant in that it enables them to be better and more creative writers. 4) The computer is an educational tool which should be utilized in all areas of the curriculum. 5) Careers curriculum is essential and enhanced by the use of CAI for accessing information and providing search and other functions.
Graduation date: 1995

Indiana University-Purdue University Indianapolis (IUPUI)
Our connections to the digital world are invoked by brands, but the intersection of branding and interaction design is still an under-investigated area. Particularly, current websites are designed not only to support essential user tasks, but also to communicate an institution's intended brand values and traits. What we do not yet know, however, is which design factors affect which aspect of a brand. To demystify this issue, three sub-projects were conducted. The first project developed a systematic approach for evaluating the branding effectiveness of content-intensive websites (BREW). BREW gauges users' brand perceptions on four well-known branding constructs: brand as product, brand as organization, user image, and brand as person. It also provides rich guidelines for eBranding researchers in regard to planning and executing a user study and making improvement recommendations based on the study results. The second project offered a standardized perceived usability questionnaire entitled DEEP (design-oriented evaluation of perceived web usability). DEEP captures the perceived website usability on five design-oriented dimensions: content, information architecture, navigation, layout consistency, and visual guidance. While existing questionnaires assess more holistic concepts, such as ease-of-use and learnability, DEEP can more transparently reveal where the problem actually lies. Moreover, DEEP suggests that the two most critical and reliable usability dimensions are interface consistency and visual guidance. Capitalizing on the BREW approach and the findings from DEEP, a controlled experiment (N=261) was conducted by manipulating interface consistency and visual guidance of an anonymized university website to see how these variables may affect the university's image. Unexpectedly, consistency did not significantly predict brand image, while the effect of visual guidance on brand perception showed a remarkable gender difference. When visual guidance was significantly worsened, females became much less satisfied with the university in terms of brand as product (e.g., teaching and research quality) and user image (e.g., students' characteristics). In contrast, males' perceptions of the university's brand image stayed the same in most circumstances. The reason for this gender difference was revealed through a further path analysis and a follow-up interview, which inspired new research directions to unpack even more the nexus between branding and interaction design.