BACKGROUND: Based on mainly vascular diseases and traumatic injuries, around 40,000 upper limb amputations are performed annually worldwide. The affected persons are strongly impaired in their physical abilities by such an intervention. Through myoelectric prostheses, affected persons are able to recover some of their abilities. METHODS: In order to control such prostheses, a system is to be developed by which electromyographic (EMG) measurements on the upper extremities can be carried out. The data obtained in this way should then be processed to recognize different gestures. These EMG measurements are to be performed by means of a suitable microcontroller and afterwards processed and classified by adequate software. Finally, a model or prototype of a hand is to be created, which is controlled by means of the acquired data. RESULTS: The signals from the upper extremities were picked up by four MyoWare sensors and transmitted to a computer via an Arduino Uno microcontroller. The Signals were processed in quantized time windows using Matlab. By means of a neural network, the gestures were recognized and displayed both graphically and by a prosthesis. The achieved recognition rate was up to 87% across all gestures. CONCLUSION: With an increasing number of gestures to be detected, the functionality of a neural network exceeds that of any fuzzy logic concerning classification accuracy. The recognition rates fluctuated between the individual gestures. This indicates that further fine tuning is needed to better train the classification software. However, it demonstrated that relatively cheap hardware can be used to create a control system for upper extremity prostheses.

There are many amputees around the world who have lost a limb through conflict, disease or an accident. Upper-limb prostheses controlled using surface Electromyography (sEMG) offer a solution to help the amputees; however, their functionality is limited by the small number of movements they can perform and their slow reaction times. Pattern recognition (PR)-based EMG control has been proposed to improve the functional performance of prostheses. It is a very promising approach, offering intuitive control, fast reaction times and the ability to control a large number of degrees of freedom (DOF). However, prostheses controlled with PR systems are not available for everyday use by amputees, because there are many major challenges and practical problems that need to be addressed before clinical implementation is possible. These include lack of individual finger control, an impractically large number of EMG electrodes, and the lack of deployment protocols for EMG electrodes site selection and movement optimisation. Moreover, the inability of PR systems to handle multiple forces is a further practical problem that needs to be addressed. The main aim of this project is to investigate the research challenges mentioned above via non-invasive EMG signal acquisition, and to propose practical solutions to help amputees. In a series of experiments, the PR systems presented here were tested with EMG signals acquired from seven transradial amputees, which is unique to this project. Previous studies have been conducted using non-amputees. In this work, the challenges described are addressed and a new protocol is proposed that delivers a fast clinical deployment of multi-functional upper limb prostheses controlled by PR systems. Controlling finger movement is a step towards the restoration of lost human capabilities, and is psychologically important, as well as physically. A central thread running through this work is the assertion that no two amputees are the same, each suffering different injuries and retaining differing nerve and muscle structures. This work is very much about individualised healthcare, and aims to provide the best possible solution for each affected individual on a case-by-case basis. Therefore, the approach has been to optimise the solution (in terms of function and reliability) for each individual, as opposed to developing a generic solution, where performance is optimised against a test population. This work is unique, in that it contributes to improving the quality of life for each individual amputee by optimising function and reliability. The main four contributions of the thesis are as follows: 1- Individual finger control was achieved with high accuracy for a large number of finger movements, using six optimally placed sEMG channels. This was validated on EMG signals for ten non-amputee and six amputee subjects. Thumb movements were classified successfully with high accuracy for the first time. The outcome of this investigation will help to add more movements to the prosthesis, and reduce hardware and computational complexity. 2- A new subject-specific protocol for sEMG site selection and reliable movement subset optimisation, based on the amputee’s needs, has been proposed and validated on seven amputees. This protocol will help clinicians to perform an efficient and fast deployment of prostheses, by finding the optimal number and locations of EMG channels. It will also find a reliable subset of movements that can be achieved with high performance. 3- The relationship between the force of contraction and the statistics of EMG signals has been investigated, utilising an experimental design where visual feedback from a Myoelectric Control Interface (MCI) helped the participants to produce the correct level of force. Kurtosis values were found to decrease monotonically when the contraction level increased, thus indicating that kurtosis can be used to distinguish different forces of contractions. 4- The real practical problem of the degradation of classification performance as a result of the variation of force levels during daily use of the prosthesis has been investigated, and solved by proposing a training approach and the use of a robust feature extraction method, based on the spectrum. The recommendations of this investigation improve the practical robustness of prostheses controlled with PR systems and progress a step further towards clinical implementation and improving the quality of life of amputees. The project showed that PR systems achieved a reliable performance for a large number of amputees, taking into account real life issues such as individual finger control for high dexterity, the effect of force level variation, and optimisation of the movements and EMG channels for each individual amputee. The findings of this thesis showed that the PR systems need to be appropriately tuned before usage, such as training with multiple forces to help to reduce the effect of force variation, aiming to improve practical robustness, and also finding the optimal EMG channel for each amputee, to improve the PR system’s performance. The outcome of this research enables the implementation of PR systems in real prostheses that can be used by amputees.

As próteses de membros superiores atualmente disponíveis no mercado não atendem a muitos dos requisitos dos seus usuários, em especial devido à funcionalidade insuficiente e a seu alto peso e custo. Este fato, aliado à importância do assunto, foi a motivação deste trabalho, que utiliza a Análise do Valor no projeto deste tipo de próteses. Para isto, propõe uma metodologia de projeto, que utiliza a mencionada Análise, e aplica a mesma às próteses de membros superiores com o objetivo de obter configurações das mesmas que contenham vantagens comparando-se com as disponíveis atualmente. A Análise do Valor trabalha com funções, e por isto, as próteses, neste trabalho, foram vistas através das funções que deveriam executar. Para a obtenção destas funções e das suas especificações, foram consultados usuários de próteses, de quem as opiniões foram consideradas as mais importantes. Após estas consultas, foi executado um brainstorming com voluntários para a obtenção de idéias de novos componentes e novos tipos de próteses. A partir do resultado das entrevistas com usuários e do brainstorming, e com base nas pesquisas realizadas, foram propostas novas configurações de próteses que procurassem atender ao máximo possível das especificações que tinham sido obtidas. Em suma, esta dissertação pretende fornecer mais subsídios para se entender o que é necessário para que as próteses de membros superiores tenham uma aceitação maior e auxiliem mais seus usuários. A metodologia proposta, por sua vez, mostrou que tem potencial para ser útil na obtenção de produtos cada vez melhores, visto que ela pode ser aplicada a produtos em geral, não somente às próteses. / The available upper limb prosthesis in the market at this moment don’t correspond to many of the users’ requirements, mainly because of the insufficient functionality and the high weight and cost. This fact, allied to the importance of the subject, was the motivation of this work, which uses the Value Analysis in this kind of prosthesis design. For this purpose, it proposes a design method, which uses the mentioned Analysis, and applies it to the upper limb prosthesis aiming to obtain this product configurations with advantages, comparing to the available prosthesis at this moment. The Value Analysis works with functions, and, because of that, the prosthesis, in this work, were seen through the functions they should execute. To obtain these functions and its specifications, prosthesis users were consulted – their opinions were considered the most important. After these consultations, it was executed a brainstorming with volunteers to obtain new prosthesis’ kinds and components ideas. With the interviews and brainstorming results, and supported by the research made, they were proposed new prosthesis configurations, which had the goal to correspond to the maximum possible of the obtained specifications. In short, this dissertation intend to provide more subsidies to comprehend what is necessary to the upper limb prosthesis to have a bigger acceptance and help more its users. The proposed design method, at its side, showed that has potential to be useful in the more and more better products obtaining, because it can be applied to the products in general, not only to the prosthesis.

Este trabalho visa contribuir para redução do grau de rejeição de próteses para membros superiores, tornando-as mais funcionais e eficientes. Tais propósitos são almejados por meio do estudo centrado no desenvolvimento de uma plataforma eletrônica de controle e nos demais constituintes de uma prótese. Dentre eles estão os atuadores, sensores, mecanismos e o programa de gerenciamento, que integra todos os componentes para as ações da prótese. Para esse trabalho foi usado somente um dedo para a execução de todos os testes, sendo esse dedo compatível com o desenvolvimento de uma prótese antropomórfica multifunção. O paciente comanda as ações da prótese ao enviar suas decisões à ela por meio de sinal mioelétrico, mas as ações da mesma são executadas de forma inconsciente. Isto é possível devido ao programa de gerenciamento, que controla os movimentos antropomórficos a partir de trajetórias definidas e também pelas informações de sensações de força e temperatura para o paciente, realimentação proprioceptiva. / This work contributes to minimize the rejection level of upper limb prosthesis, keeping it more function and efficient. This achieved by the development of a control electronic platform and the others prosthesis components, like actuators, sensors, mechanisms and the management program, that integrate all the components to actions of prosthesis. In this work was used only one finger to perform of all tests, and this finger is compatible with the development of a multifunction anthropomorphic prosthesis. The user command comes from myoelectric signal, but the actions in the prosthesis are executed unconsciously. The management program control the anthropomorphic movements based on defined trajectory and create information of force and temperature sensation to the user, proprioceptive feedback.

Este trabalho visa contribuir para redução do grau de rejeição de próteses para membros superiores, tornando-as mais funcionais e eficientes. Tais propósitos são almejados por meio do estudo centrado no desenvolvimento de uma plataforma eletrônica de controle e nos demais constituintes de uma prótese. Dentre eles estão os atuadores, sensores, mecanismos e o programa de gerenciamento, que integra todos os componentes para as ações da prótese. Para esse trabalho foi usado somente um dedo para a execução de todos os testes, sendo esse dedo compatível com o desenvolvimento de uma prótese antropomórfica multifunção. O paciente comanda as ações da prótese ao enviar suas decisões à ela por meio de sinal mioelétrico, mas as ações da mesma são executadas de forma inconsciente. Isto é possível devido ao programa de gerenciamento, que controla os movimentos antropomórficos a partir de trajetórias definidas e também pelas informações de sensações de força e temperatura para o paciente, realimentação proprioceptiva. / This work contributes to minimize the rejection level of upper limb prosthesis, keeping it more function and efficient. This achieved by the development of a control electronic platform and the others prosthesis components, like actuators, sensors, mechanisms and the management program, that integrate all the components to actions of prosthesis. In this work was used only one finger to perform of all tests, and this finger is compatible with the development of a multifunction anthropomorphic prosthesis. The user command comes from myoelectric signal, but the actions in the prosthesis are executed unconsciously. The management program control the anthropomorphic movements based on defined trajectory and create information of force and temperature sensation to the user, proprioceptive feedback.

As próteses de membros superiores atualmente disponíveis no mercado não atendem a muitos dos requisitos dos seus usuários, em especial devido à funcionalidade insuficiente e a seu alto peso e custo. Este fato, aliado à importância do assunto, foi a motivação deste trabalho, que utiliza a Análise do Valor no projeto deste tipo de próteses. Para isto, propõe uma metodologia de projeto, que utiliza a mencionada Análise, e aplica a mesma às próteses de membros superiores com o objetivo de obter configurações das mesmas que contenham vantagens comparando-se com as disponíveis atualmente. A Análise do Valor trabalha com funções, e por isto, as próteses, neste trabalho, foram vistas através das funções que deveriam executar. Para a obtenção destas funções e das suas especificações, foram consultados usuários de próteses, de quem as opiniões foram consideradas as mais importantes. Após estas consultas, foi executado um brainstorming com voluntários para a obtenção de idéias de novos componentes e novos tipos de próteses. A partir do resultado das entrevistas com usuários e do brainstorming, e com base nas pesquisas realizadas, foram propostas novas configurações de próteses que procurassem atender ao máximo possível das especificações que tinham sido obtidas. Em suma, esta dissertação pretende fornecer mais subsídios para se entender o que é necessário para que as próteses de membros superiores tenham uma aceitação maior e auxiliem mais seus usuários. A metodologia proposta, por sua vez, mostrou que tem potencial para ser útil na obtenção de produtos cada vez melhores, visto que ela pode ser aplicada a produtos em geral, não somente às próteses. / The available upper limb prosthesis in the market at this moment don’t correspond to many of the users’ requirements, mainly because of the insufficient functionality and the high weight and cost. This fact, allied to the importance of the subject, was the motivation of this work, which uses the Value Analysis in this kind of prosthesis design. For this purpose, it proposes a design method, which uses the mentioned Analysis, and applies it to the upper limb prosthesis aiming to obtain this product configurations with advantages, comparing to the available prosthesis at this moment. The Value Analysis works with functions, and, because of that, the prosthesis, in this work, were seen through the functions they should execute. To obtain these functions and its specifications, prosthesis users were consulted – their opinions were considered the most important. After these consultations, it was executed a brainstorming with volunteers to obtain new prosthesis’ kinds and components ideas. With the interviews and brainstorming results, and supported by the research made, they were proposed new prosthesis configurations, which had the goal to correspond to the maximum possible of the obtained specifications. In short, this dissertation intend to provide more subsidies to comprehend what is necessary to the upper limb prosthesis to have a bigger acceptance and help more its users. The proposed design method, at its side, showed that has potential to be useful in the more and more better products obtaining, because it can be applied to the products in general, not only to the prosthesis.

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Esta tese de Doutorado busca contribuir na formação de subsídios científicos tanto para o projeto de uma prótese antropomórfica para membros superiores, quanto para a criação de um ambiente de treinamento, ou seja, um ambiente virtual de ação e realimentação das sensações, que poderá incorporar os mecanismos, atuadores, sensores ou estimuladores desenvolvidos. Ao final desta pesquisa, foram projetados e testados os mecanismos, sensores e alguns dispositivos de realimentação que farão parte do desenvolvimento de uma prótese de mão, a Mão de São Carlos, que possuirá características antropomórficas, para reproduzir os movimentos naturais da mão humana com um controle simplificado para o paciente. A motivação principal deste trabalho é diminuir o índice de rejeição das próteses para membros superiores, facilitando seu processo de treinamento e controle / This Doctoral thesis should contribute to the gathering of scientific subsidies for the project of a multifunction anthropomorphic upper limb prosthesis, in special the artificial hand, and for the creation of a training software, i.e., a software for the sensory's action and feedback. At the end of this research, the mechanisms, sensors, actuators and some feedback devices were designed and tested, that will be part of the development of a hand prosthesis, the São Carlos Hand, which will possess anthropomorphic characteristics, a simplified control for the patient and will reproduce the natural movements of the human hand. The main motivation of this work is to reduce the rejection index of the upper limb prosthesis, facilitating training process and control