The project concerned pathological tremor, which is the most common movement disorder found in human pathology. It may be defined as an involuntary, approximately rhythmic and roughly sinusoidal movement, which occurs mainly on the upper limb. Although tremor itself is not life-threatening, it may reduce considerably the patient’s quality of life, since the abilities required to perform simple Activities of Daily Living (ADL), such as inserting the key in the keyhole, is seriously decreased. Tremor is associated with several pathologies, such as Parkinson's Disease (PD) and cerebellar dysfunctions, and diagnose and quantification by physicians is not straightforward. Furthermore, pharmacological and surgical therapies available today present several limitations.
Hence, the main goal of the project is the study of an alternative therapy for those that experience one of such pathologies. This alternative solution is based on the active tremor compensation of the upper limbs via Functional Electrical Stimulation (FES). The project, which is coordinated by Prof. Philippe Poignet, involves a research laboratory (LIRMM), a biomedical company (MXM/Neuromedics) expert in FES, represented by Jean-Louis Divoux, which provides financial and technical support, and two clinical partners (the Neurology Department at the CHU of Montpellier, and Propara Rehabilitation Center). Also, the project is executed with the scientific collaboration of the Biorobotics Group at the Nanyang Technological University, Singapore.
The first part of my study was devoted to the development of algorithms to estimate in real-time the time-varying features of pathological tremor. Different filters and models were compared, as well as tremors related to different pathologies. Also, the methods were developed to identify tremor components from the acquired signal, considering that the applied sensors also measure voluntary motion. In our experiments, signals from low cost inertial sensors and surface electromyography (sEMG) are used to characterise tremor. For that purpose, a multichannel experimental acquisition system was developed and is currently being used by our clinical partner at the CHU Montpellier. To evaluate the performance of the proposed techniques, we also employ other technologies, such as digitising tablets and optical sensors. The techniques developed in the work may be also used to provide useful clinical measures to quantify tremor for medical studies and diagnose.
The project is composed of 4 subsections (two scientific, one technological and one clinical) which are successively
From that list, my activities concerned parts 1 and particularly 2. Below the approach adopted in the project is illustrated, as well as the experimental setup.
I have also worked on modelling issues related to pathological tremor and musculoskeletal systems. This study is important both in terms of understanding how tremor affects the respective muscles and motions and in the development of new strategies to attenuate tremor using FES or different technologies. Furthermore, this study has provided a simulation environment which may be used to evaluate different methods before real experiments.
Lately, my work has been concentrated on the development of FES-based tremor attenuation strategies. We use a multichannel stimulator, the Prostim, developed by MXM and the DEMAR, controlled by a real-time Linux system. Open-loop experiments involving tremor patients have been conducted in order to validate a new approach to tremor attenuation based on the modulation of joint impedance using FES. A closed-loop strategy has also been proposed in order to improve the overall performance of the system and increase the patient comfort. This new approach has already been evaluated in healthy subjects.
Further details may be found within the concerned publications.
Hence, the main goal of the project is the study of an alternative therapy for those that experience one of such pathologies. This alternative solution is based on the active tremor compensation of the upper limbs via Functional Electrical Stimulation (FES). The project, which is coordinated by Prof. Philippe Poignet, involves a research laboratory (LIRMM), a biomedical company (MXM/Neuromedics) expert in FES, represented by Jean-Louis Divoux, which provides financial and technical support, and two clinical partners (the Neurology Department at the CHU of Montpellier, and Propara Rehabilitation Center). Also, the project is executed with the scientific collaboration of the Biorobotics Group at the Nanyang Technological University, Singapore.
The first part of my study was devoted to the development of algorithms to estimate in real-time the time-varying features of pathological tremor. Different filters and models were compared, as well as tremors related to different pathologies. Also, the methods were developed to identify tremor components from the acquired signal, considering that the applied sensors also measure voluntary motion. In our experiments, signals from low cost inertial sensors and surface electromyography (sEMG) are used to characterise tremor. For that purpose, a multichannel experimental acquisition system was developed and is currently being used by our clinical partner at the CHU Montpellier. To evaluate the performance of the proposed techniques, we also employ other technologies, such as digitising tablets and optical sensors. The techniques developed in the work may be also used to provide useful clinical measures to quantify tremor for medical studies and diagnose.
The project is composed of 4 subsections (two scientific, one technological and one clinical) which are successively
- Modeling of pathological tremor
- Strategies for active tremor compensation using FES
- Design of a prototype for a wearable orthosis
- Clinical evaluation
From that list, my activities concerned parts 1 and particularly 2. Below the approach adopted in the project is illustrated, as well as the experimental setup.
I have also worked on modelling issues related to pathological tremor and musculoskeletal systems. This study is important both in terms of understanding how tremor affects the respective muscles and motions and in the development of new strategies to attenuate tremor using FES or different technologies. Furthermore, this study has provided a simulation environment which may be used to evaluate different methods before real experiments.
Lately, my work has been concentrated on the development of FES-based tremor attenuation strategies. We use a multichannel stimulator, the Prostim, developed by MXM and the DEMAR, controlled by a real-time Linux system. Open-loop experiments involving tremor patients have been conducted in order to validate a new approach to tremor attenuation based on the modulation of joint impedance using FES. A closed-loop strategy has also been proposed in order to improve the overall performance of the system and increase the patient comfort. This new approach has already been evaluated in healthy subjects.
Further details may be found within the concerned publications.
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