Hardware Design of Low Cost Myoelectric Controlled Prosthetic Hand for Engineering Laboratory

Abstract

This study presents a low cost, two-channel, on-off type, constant speed myo-electric controlled prosthetic hand project as an educational tool for Biomedical/Control/Mechatronic Engineering. Surface Electromyogram (sEMG) signals were recorded from the muscles of flexor carpi ulnaris and extensor digitorium on the forearm. Signal conditioning of these signals is performed in the analog stages of the system, before passing it on to a microcontroller for further filtering and implementation of control. The control logic is simplified to represent the muscles as being active or inactive, resulting in a very simple on/off control based on the two signals. The on/off control signals are used to drive a myo-electric controlled prosthetic hand-powered by a hobby RC servo motor. A printed circuit board has been designed for the analog stages of the system, and a simple Arduino Microcontroller is used for the digital stages. Other commercial off-the-shelf components were used to keep the cost of the hardware and the software components as low as possible. This project was used as a teaching aid for the final year undergraduate students to demonstrate the use of simple myo-electric signal processing and control techniques.