A vision driven wayfinding simulation system based on the architectural features perceived in the office environment

Human wayfinding in the built environment is extensively investigated in the last 50 years. One major aspect of the outcome is the decision made on the egresses based on the information perceived during the wayfinding. Information acquired of the environment could be categorized into several types, namely the verbal (information obtained from the reception, staff members, etc.), the graphic (map of the environment, signage showing the location or pointing to certain location, etc.), the architectural (entrances, stairs, corridors, etc.), and the spatial (spatial relationship of objects in the environment). Early analyses of indoor wayfinding suggested that signage and colour codes could provide landmarks, but the addition of these cues after construction can be futile. This suggests that, architectural information has a significant influence on individual’ s decision making. However, inmost researches, the function of the architectural information was underestimated -- it was often treated as the constraint of the architectural spaces. The presented research aims at developing of an agent-based system that can find certain destination in a virtual office building environment using artificial vision and cognition based on the architectural features in this built environment. During the wayfinding, this agent’ s egress choices follows an estimated model that based on experimental data with real human. Before running the experiments with real humans, pre-experiments were conducted to investigate the conditions for vision research using standard LCD monitors. The thresholds obtained in the pre-experiments for lighting in the virtual environment and for the testing environment served as input to the development of the following experiments. In the first experiment subjects were asked to make choices between two egresses in a sequence of isolated convex rooms. The architectural features of these rooms and of the egresses were varied systematically. The room features included: size and colour; while the egress features were: colour, distance, angle and width. From the collected data a preference function was estimated on egress choice given the architectural features. In the second experiment the assignment was to find the destination and then return to the start in a virtual building. Subjects executed three different assignments given different locations for the destination and the start, and every assignment was repeated two to three times subsequently. Each subject’ s routes in the experiments were recorded. From these routes search strategies used for wayfinding were determined, namely: Orientation Based, Architectural Features Based, Boundary Based, Random Choice, Minimum rooms and Shortest Distance. A preference function was estimated for the next room choice, based upon the architectural features of the current room, and the given familiarity of the environment. The implemented agent uses a simplified version of the virtual building model. This simplified version only includes those architectural elements and features that are relevant for vision driven navigation, i.e. the type of egress, egress colour, egress width, room colour and room size. Room colour is converted into three levels of grey. The agent’ s wayfinding behaviour is validated with the hit ratio, the average visit frequency of each room, and the average total number of rooms visited, respectively. The agent-based simulation system developed in not only an interpretation of the empirical findings obtained from the research, but it is also applicable for testing and evaluation purposes in architectural design problems. After certain transformations, a CAD model of an office environment can be presented to the simulation system as input. By setting the wayfinding task, the designed agent can be employed to predict how individuals may behave in this office environment in reality. This helps the architects, with regard to wayfinding efficiency and space utility, to improve their design

Behavioural morphisms in virtual environments

One of the largest application domains for Virtual Reality lies in simulating the Real World. Contemporary applications of virtual environments include training devices for surgery, component assembly and maintenance, all of which require a high fidelity reproduction of psychomotor skills. One extremely important research question in this field is: "How closely does our facsimile of a real task in a virtual environment reproduce that Task?" At present the field of Virtual Reality is answering this question in subjective terms by the concept of presence and in objective terms by measures of task performance or training effectiveness ratios. [Continues.

Vers des environnements virtuels plus écologiques : étude des modifications du comportement moteur en réalité virtuelle lors de l'ajout d'informations haptiques par un mécanisme parallèle entraîné par câbles

Introduction : Les nouvelles technologies qui permettent de capter et d’analyser les mouvements des utilisateurs ne cessent de se développer et représentent un potentiel intéressant dans le domaine de la santé. Grâce à l’essor de ces nouvelles technologies, des systèmes de réalité virtuelle (RV) clefs en main intègrent les services de réadaptation, et les études démontrent leur capacité à optimiser la rééducation motrice et l’évaluation des clients présentant des troubles du contrôle moteur. Le marché de la RV est ainsi en pleine expansion, et l’ajout d’informations haptiques permettant de modéliser les caractéristiques physiques des entités virtuelles représente un intérêt considérable pour améliorer l’écologie des environnements virtuels (EVs) et le transfert des apprentissages aux activités quotidiennes. Toutefois, l’effet de l’ajout de ces informations sur le comportement moteur des sujets demeure très peu connu. L’objectif principal de cette thèse était ainsi d’évaluer l’impact de l’ajout d’informations haptiques, par un mécanisme parallèle entrainé par câbles (robot à câbles), sur le contrôle moteur de sujets sains, lors de la réalisation de tâches complexes et fonctionnelles dans des EVs. Les deux hypothèses principales étaient que cet ajout améliore le contrôle du mouvement lors de tâche de manutention d’objet ayant des contraintes environnementales statiques, et modifie les stratégies locomotrices proactives en présence de contraintes dynamiques. Méthode : Le comportement moteur de participants sains a été analysé lors de la réalisation de deux tâches. En premier lieu, une tâche de manutention de caisse nécessitant la préhension et le déplacement d’une caisse à partir d’une posture debout a été étudiée. Celle-ci a été réalisée dans un environnement réel et dans des EVs, en absence et en présence d’informations haptiques, relatives aux contraintes physiques de l’étagère et de la caisse manipulée, fournies grâce à un robot à câbles (Chapitre 3, N=12). En second lieu, une tâche nécessitant l’évitement d’avatars au cours de la marche sur un tapis roulant a été réalisée en présence et en absence de risque de contact physique avec les avatars, délivré par un robot à câbles (Chapitre 4, N=10). Les EVs étaient vus au travers d’un visiocasque. Résultats : La première étude a démontré une amélioration des paramètres spatiaux du mouvement réalisé dans l’EV en présente d’informations haptiques, au cours des différentes phases de la tâche de manutention (préhension, montée et descente de la caisse). L’organisation spatiale du mouvement était ainsi plus similaire à ce qui était observé dans un environnement réel, avec un meilleur respect des contraintes environnementales (éloignement plus important de la caisse avec l’étagère, trajectoire plus longue). De plus, le contrôle du mouvement était influencé par la demande de précision requise pour ne pas toucher les étagères en présence d’informations haptiques uniquement. La deuxième étude a démontré la mise en place de stratégies motrices plus précautionneuses pour éviter les avatars lors de l’ajout d’informations haptiques. Les participants tendaient à anticiper plus précocement l’évitement des avatars. Ils maintenaient une distance minimale plus importante avec les avatars et conservaient un espace péripersonnel plus large, indépendamment de l’angle d’approche de l’avatar. Conclusion : L’ajout d’informations haptiques dans les EVs impacte les stratégies motrices proactives des participants sains aussi bien lors de la tâche de manutention de caisse que de locomotion avec évitement d’avatars. Les résultats suggèrent que l’ajout d’informations haptiques favorise la prise en compte des entités virtuelles lors de la planification mouvement. Ces informations haptiques imposent en effet des restrictions plus réalistes dans les possibilités d’actions fournies par les EVs, et modifient probablement l’évaluation des conséquences que représente le contact avec les entités virtuelles. Il serait pertinent de poursuivre l’étude de l’influence de ces informations afin de proposer à des clients ayant des déficiences motrices des environnements encore plus écologiques, qui favorisent l’évaluation et la prise en compte des risques implicites que représentent les entités environnementales.Introduction: New technologies that capture and analyze user movement are constantly developing and represent a great potential in healthcare. Thanks to the recent technological advances, turnkey virtual reality (VR) systems are progressively integrated into the rehabilitation setting, and studies have demonstrated their ability to optimise sensorimotor rehabilitation and clinical assessment of people with motor control disorders. The market for VR is growing and adding haptic feedback that provides physical characteristics to virtual entities represents a great potential to improve the ecological validity of virtual environments (VE) and to the transfer of learning to daily tasks. However, the impact that adding haptic feedback has on motor behavior remains poorly understood. The main objective of this thesis was to assess the impact of adding haptic feedback, using a novel cable-driven parallel robot, on the motor control of healthy participants during complex, functional tasks in VEs. The two mains hypotheses were that haptic feedback improves motor control during a handling task with static environmental constraints and modifies proactive locomotor strategies in the presence of dynamic constraints. Method: The motor behavior of healthy participants was analysed during two tasks. First, a manual handling task was studied during which participants grasped and moved a crate while standing. This task was realised in a real environment and in VEs with the absence and the presence of haptic information. The latter simulated the physical constraints of the shelf and the crate to be manipulated using a cable-driven robot (Chapter 3, N=12). Second, avatar avoidance tasks were realised when participants walked on a self-paced treadmill in the absence and then in the presence of a risk of physical contact with avatars. Contact was simulated by a cable-driven robot (Chapter 4, N=10). VEs were viewed through a head mounted display for all tasks. Results: The first study showed that adding haptic feedback to the VE improved spatial parameters of movement realised in a VE during all phases of movement (reaching, ascent and descent phases). The spatial organisation of movement was closer to those observed in a physical environment, and better respected environmental constraints (higher clearances from the shelf and longer trajectories). Moreover, movement control was influenced by task precision required to avoid any contact with the shelf in the presence of haptic feedback only. The second study demonstrated that when avoiding avatars in VR, more cautious behavior was measured in the presence of potential physical contact. Participants tended to start their avoidance strategy earlier and increased minimum clearance along with a larger personal space regardless of the avatar’s approach angle. Conclusion: Adding haptic feedback in VEs impacts the proactive motor strategies of healthy participants during a manual handling task as well as a locomotor task involving the avoidance of avatars. These results suggest that adding haptic feedback enhances one’s consideration of virtual entities during movement planning. Haptic information imposes more realistic restrictions on the actions afforded by EVs, and likely modifies the perceived consequences of potential contact with virtual entities. It will be important to continue to study the impact of haptic feedback within VEs to provide even more ecological environments to people with motor deficits in order to improve assessment and the consideration of implicit risks posed by the environment

Desarrollo de un protocolo de realidad virtual con el objetivo de la reeducación funcional del movimiento de alcance en pacientes con Parkinson

Programa Oficial de Doutoramento en Neurociencias. 5028V01[Resumen] Los estudios y terapias basados en la creación de un entorno de realidad virtual son cada vez de uso más frecuente en diversas áreas de neuro-rehabilitación, y ello es debido a que la realidad virtual permite el diseño de actividades y movimientos funcionales específicos para su entrenamiento. En el presente trabajo se diseñó un sistema de evaluación y entrenamiento del movimiento de alcance en un entorno de realidad virtual de bajo coste, para la intervención en distintas poblaciones. Como estudio central de la tesis se evaluó su utilidad en el entrenamiento de esta actividad funcional en enfermos de Parkinson. Se planteó el estudio piloto atendiendo a la hipótesis de que la observación de una acción podría inducir mejoras en la realización de la misma acción por parte de los pacientes, y así plantearse como una posible estrategia terapéutica que facilite un re-aprendizaje motor, con la consiguiente mejora en la función motora de la enfermedad. Para lograr estos objetivos se realizaron una serie de estudios en los que se evaluaban variables cinemáticas y neurofisiológicas, mediante el uso de acelerometría, electromiografía y estimulación magnética transcraneal. Los resultados de la terapia basada en la observación durante la ejecución en realidad virtual mostraron cambios modestos en la ejecución motora de los pacientes. Estos hallazgos indican que el uso de la realidad virtual combinada con la observación de un movimiento durante su ejecución podría mejorar el movimiento de alcance en la enfermedad de Parkinson, pero sería necesaria la realización de más estudios en los que se optimice el protocolo de entrenamiento.[Resumo] Os estudos e terapias baseadas na creación dun ambiente de realidade virtual son cada vez de uso máis frecuente en varias áreas de neuro-rehabilitación, isto débese a que a realidade virtual permite o deseño de actividades específicas e movementos funcionais específicos para o seu adestramento. Neste traballo deseñouse un sistema de avaliación e adestramento do movemento de alcance nun entorno de realidade virtual de baixo custe para a intervención en diferentes pobacións. Como estudo central da tese, avaliouse a súa utilidade no adestramento desta actividade funcional en enfermos de Parkinson. Desenrolouse un estudo piloto considerando a hipótese de que a observación dunha acción podería inducir melloras na execución da mesma acción por parte dos pacientes, e así poder plantearse como unha potencial estratexia terapéutica para facilitar a re-aprendizaxe motora, mellorando a función motora da enfermidade. Para acadar estes obxectivos realizáronse unha serie de estudos nos que se avaliaban variables cinemáticas e neurofisiolóxicas, mediante o emprego da acelerometría, eletromiografía e estimulación magnética transcraniana. Os resultados da terapia baseada na observación durante a execución en realidade virtual mostraron cambios modestos na execución motora dos pacientes. Estes resultados indican que o uso de realidade virtual combinado coa observación dun movemento durante a súa execución pode mellorar o movemento de alcance na enfermidade de Parkinson, pero sería necesaria a realización de máis estudos nos que se optimice o protocolo de adestramento.[Abstract] Studies and therapies based on the creation of a virtual reality environment are increasingly used in various areas of neuro-rehabilitation. Perhaps, the reason for this is virtual reality allows the design of specific functional activities and movements for their traning. In the present work, we designed a low-cost virtual reality system for the evaluation and traning of arm reaching movements in different clinical populations. As a central study of the thesis, we evaluated the effect of training the reaching movement in Parkinson’s disease patients. A pilot study was conceived on the hypothesis that the observation of an action would facilitate the performance of the same action in the patients, which would suggest a possible therapeutic strategy that facilitates motor re-learning and improves motor function in the disease. To achieve these objectives, a series of studies were carried out, in which kinematic and neurophysiological variables were evaluated with accelerometry, electromyography or transcranial magnetic stimulation. The results of the therapy based on movement observation during the execution in virtual reality showed mild changes in patient’s motor execution. These findings indicate that the use of virtual reality combined with the observation of a movement during its execution might improve reaching movements in Parkinson’s disease, but further research should optimize the intervention protocol