Multifunction Controlled 3D Printed Hand Prosthesis with the Myo Arm-Band by Hand Amputees

Upper limb amputations are highly impairing injuries that can substantially limit the quality of life of a person. The most advanced dexterous prosthetic hands have remarkable mechanical features. However, in most cases, the control systems are a simple extension of basic control protocols, making the use of the prosthesis not intuitive and sometimes complex. Furthermore, the cost of dexterous prosthetic hands is often prohibitive, especially for the pediatric population and developing countries. 3D-printed hand prostheses can represent an opportunity for the future. Open 3D models are increasingly being released, even for dexterous prostheses that are capable of moving each finger individually and actively rotating the thumb. However, the usage and testing of such devices by hand amputees (using electromyography and classification methods) is not well explored. This article aims to investigate the usage of a cost-effective system composed of a 3D-printed hand prosthesis and a low-cost myo electric armband. Two subjects with trans-radial amputation were asked to wear a custom-made socket supporting the Hand and the Thalmic Labs Myo armband. Afterward, the subjects were asked to control and use the prosthetic and to grasp several objects by attempting to perform a set of different hand gestures. Both the Hand and the Myo armband performed well during the test, which is encouraging considering that the Hand was developed as a research platform. The results are promising and show the feasibility of the multifunction control of dexterous 3D- printed hand prostheses based on low-cost setups. Factors such as the level of the amputation, neuromuscular fatigue, and mechanical limitations of the 3D-printed hand prosthesis can influence the performance of the setup. Practical aspects such as usability and robustness will need to be addressed for successful application in daily life.