MyoFit: A new approach to suspension for upper limb myoelectric prostheses

DESCRIPTION provided by applicant A new approach to suspension for upper limb myoelectric prostheses The overall goal of our research program is to empower upper limb amputees to be productive and independent For these individuals one of the most promising developments in the past decade has been the introduction of fully dexterous terminal devices However an effective and intuitive control strategy has remained elusive Myoelectric control typically utilizing two surface EMG electrodes works well for one or two degree of freedom devices but it is not as effective when dealing with a large number of movement classes such as when attempting to discriminate amongst andquot hand openandquot andquot index finger pointandquot andquot fine pinchandquot and so on Thus significant research has been undertaken on decoding the amputeeandapos s intention using signals from a larger number of surface EMG electrodes typically eight pairs However optimal performance is dependent on high quality surface EMG signal acquisition Small changes in electrode position or in contact between the electrode and the skin results in significant degradation in system performance One primary reason is that the design of the standard anatomically suspended prosthesis did not anticipate the evolution of prosthesis technology to include this need for highly stable multichannel surface EMG signal acquisition Thus there is a need to fundamentally rethink prosthesis design in light of the new opportunity to achieve dexterous control Specifically in this Fast Track effort we propose development of the MyoFit system to replace the standard anatomical suspended prosthesis It includes a roll on silicone gel liner which is fabricated to incorporate eight flexible surface EMG electrodes The liner and by extension the electrodes interfaces with the socket and frame of the prosthesis via a two part pin lock system The system enables a stable electrode skin interface including when the prosthesis is bearing load and when it is being moved to various positions in the workspace During Phase I we will develop and complete engineering validation of the liner and the lock In Phase II we will complete system integration and FDA regulatory clearance We will also undertake a clinical study to evaluate the functional benefits of the MyoFit system as compared to the standard anatomically suspended prosthesis It is our ultimate goal for the MyoFit system to enable upper limb amputees to achieve a superior clinical functional outcome PUBLIC HEALTH RELEVANCE The goal of our project is to improve the lives of upper extremity amputees Specifically we are developing several technologies which will allow electrical signals generated by the residual muscles in an amputees arm to be accurately read This will allow for an amputee to control the prosthetic device that they are using including prosthetic hands that can move in a variety of ways