Vision-based hand Wheel-chair control

Several studies have shown that people with disabilities benefit substantially from access to a means of independent mobility and assistive technology. Researchers are using technology originally developed for mobile robots to create easier to use wheelchairs. With this kind of technology people with disabilities can gain a degree of independence in performing daily life activities. In this work a computer vision system is presented, able to drive a wheelchair with a minimum number of finger commands. The user hand is detected and segmented with the use of a kinect camera, and fingertips are extracted from depth information, and used as wheelchair commands.

Generic system for human-computer gesture interaction: applications on sign language recognition and robotic soccer refereeing

Hand gestures are a powerful way for human communication, with lots of potential applications in the area of human computer interaction. Vision-based hand gesture recognition techniques have many proven advantages compared with traditional devices, giving users a simpler and more natural way to communicate with electronic devices. This work proposes a generic system architecture based in computer vision and machine learning, able to be used with any interface for human-computer interaction. The proposed solution is mainly composed of three modules: a pre-processing and hand segmentation module, a static gesture interface module and a dynamic gesture interface module. The experiments showed that the core of visionbased interaction systems could be the same for all applications and thus facilitate the implementation. For hand posture recognition, a SVM (Support Vector Machine) model was trained and used, able to achieve a final accuracy of 99.4%. For dynamic gestures, an HMM (Hidden Markov Model) model was trained for each gesture that the system could recognize with a final average accuracy of 93.7%. The proposed solution as the advantage of being generic enough with the trained models able to work in real-time, allowing its application in a wide range of human-machine applications. To validate the proposed framework two applications were implemented. The first one is a real-time system able to interpret the Portuguese Sign Language. The second one is an online system able to help a robotic soccer game referee judge a game in real time.

Generic system for human-computer gesture interaction

Hand gestures are a powerful way for human communication, with lots of potential applications in the area of human computer interaction. Vision-based hand gesture recognition techniques have many proven advantages compared with traditional devices, giving users a simpler and more natural way to communicate with electronic devices. This work proposes a generic system architecture based in computer vision and machine learning, able to be used with any interface for humancomputer interaction. The proposed solution is mainly composed of three modules: a pre-processing and hand segmentation module, a static gesture interface module and a dynamic gesture interface module. The experiments showed that the core of vision-based interaction systems can be the same for all applications and thus facilitate the implementation. In order to test the proposed solutions, three prototypes were implemented. For hand posture recognition, a SVM model was trained and used, able to achieve a final accuracy of 99.4%. For dynamic gestures, an HMM model was trained for each gesture that the system could recognize with a final average accuracy of 93.7%. The proposed solution as the advantage of being generic enough with the trained models able to work in real-time, allowing its application in a wide range of human-machine applications.

Plataforma para suporte ao ciclo de vida de organizações virtuais e seleção dinâmica de parceiros e fornecedores

Tese de Doutoramento em Engenharia Industrial e de Sistemas

Potential implications of ketamine anesthesia on zebrafish behavior

Dissertação de mestrado integrado em Psicologia

Quality costs analysis: case study in the automotive industry

Dissertação de mestrado integrado em Engenharia e Gestão Industrial

Implementação de um sistema de gestão e monitorização de embalagens retornáveis em ambiente industrial

Dissertação de mestrado em Engenharia de Sistemas

Caracterização química e física de conformal coatings envolvidos na produção de PCBA's

Dissertação de mestrado integrado em Engenharia de Materiais

Segmentação do tecido tumoral cerebral em imagens de ressonância magnética

Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Eletrónica Médica)

Segmentação de imagens fetais com potencial para desenvolvimento de ferramentas de apoio ao diagnóstico

Programa Doutoral em Engenharia Eletrónica e de Computadores

Development of procedures for the design, optimization and manufacturing of customized orthopaedic and trauma implants: Geometrical/anatomical modelling from 3D medical imaging

Tese de Doutoramento (Programa Doutoral em Engenharia Biomédica)

O direito de livre revogação nos contratos celebrados à distância e fora do estabelecimento comercial

Dissertação de mestrado em Direito dos Contratos e da Empresa

Segmentação morfológica e dificuldades de leitura em crianças com perturbações de leitura e escrita

O presente estudo pretende verificar se existe uma correlação entre consciência morfológica e desempenho em leitura e escrita (mais precisamente, na componente de leitura) em crianças com e sem dificuldades ou perturbação de leitura e escrita. Para cumprir este objetivo, aplicou-se, numa amostra de crianças falantes de português europeu, dois instrumentos de avaliação: o “Teste de Idade de Leitura” e uma Prova de Consciência Morfológica, especificamente criada para o efeito. O grupo experimental (GE) inclui crianças com diagnóstico de dificuldades ou perturbação de leitura e escrita; o grupo de controlo (GC) não. Após a análise dos dados, conclui-se que existe uma diferença estatisticamente significativa entre os grupos de crianças em estudo, uma vez que o GC revela um desempenho superior ao GE em ambas as provas aplicadas. Os resultados obtidos demonstram ainda uma correlação estatisticamente significativa entre o desempenho das crianças no domínio de leitura e o desempenho das crianças ao nível da consciência morfológica. A correlação mostra-se consideravelmente mais forte no GE do que no GC. Deste modo, conclui-se que a estimulação da consciência morfológica pode efetivamente facilitar e auxiliar o desenvolvimento da aprendizagem leitora em crianças, sobretudo em crianças com dificuldades nestes domínios.