Made available in DSpace on 2015-03-05T13:53:43Z (GMT). No. of bitstreams: 0 Previous issue date: 28 / Nenhuma / Neste trabalho foi desenvolvido um sistema de controle robusto para robôs móveis autônomos que é capaz de operar e de se adaptar a diferentes ambientes e condições. Para isso foi proposta uma arquitetura de controle híbrida (COHBRA), integrando as duas principais técnicas de controle robótico (controle deliberativo e controle reativo). Esta arquitetura de controle utiliza uma abordagem de três camadas para integrar uma camada vital (controle reativo), uma camada funcional (seqüenciador) e uma camada deliberativa (controle deliberativo). A comunicação entre as diversas camadas é realizada através de uma área de memória compartilhada, inspirada na abordagem Blackboard. A arquitetura de controle possui um esquema de múltiplas representações internas do ambiente: representação poligonal, representação matricial e representação topológica / semântica. O sistema de controle desenvolvido tem a capacidade de navegar em um ambiente dinâmico, desviando tanto de obstáculos estáticos como de obstáculos móveis / In this work we developed a robust control system for autonomous mobile robots capable of operating and adapting in various environments and conditions. In order to accomplish this objective an hybrid control architecture (COHBRA) was proposed, integrating the two main techniques of robotic control: deliberative control and reactive control. This control architecture uses a three layers approach to integrate a vital layer (reactive control), a functional layer (sequencer) and a deliberative layer (deliberative control). The communication between the three layers uses a shared memory approach, inspired in the Blackboard approach. The control architecture has a structure of multiple internal representations of the environment: polygonal representation, matricial representation and topological/semantic representation. The control system has the ability to navigate in a dynamic environment, avoiding static obstacles and unexpected mobile obstacles. The deliberative layer uses the A* algorithm to calcu

Current bio-robotic assistive devices have developed into intelligent and dexterous machines. However, the sophistication of these wearable devices still remains limited by the inherent difficulty in controlling them by sensing user-intention. Even the most commonly used sensing method, which detects the electrical activity of skeletal muscles, offer limited information for multi-function control. An alternative bio-sensing strategy is needed to allow for the assistive device to bear more complex functionalities. In this thesis, a different sensing approach is introduced using Pulsed-Wave Doppler ultrasound in order to non-invasively detect small tendon displacements in the hand. The returning Doppler shifted signals from the moving tendon are obtained with a new processing technique. This processing technique involves a unique way to acquire raw data access from a commercial clinical ultrasound machine and to process the signal with Fourier analysis in order to determine the tendon displacements. The feasibility of the proposed sensing method and processing technique is tested with three experiments involving a moving string, a moving biological beef tendon and a moving human hand tendon. Although the proposed signal processing technique will be useful in many clinical applications involving displacement monitoring of biological tendons, its uses are demonstrated in this thesis for ultrasound-based user intention analysis for the ultimate goal of controlling assistive exoskeletal robotic hands.