Metacarpus flexion and palmar prehension using wrist movement based MEMS accelerometer

Many people lose their gripping action as a result of the metacarpus and phalanges fractures and amputations. The primary function of the hand is prehension which involves holding and manipulation of objects. There are various ways of replacing the flexion functioning of the hand which includes prostheses, orthotics and robotics. Prostheses tend to be minimally invasive and this work explores the possibility of replacing the malfunctioning of the hand's gripping function. A Micro Electro-Mechanical System (MEMS) based type tri-axis accelerometer can sense movement from anterior surface of the hand using acceleration in the different axes. A microcontroller is used to convert the acceleration from sensor and calculate the tilt angle and the angle is then used to control a prosthetic hand gripper. Depending on the set threshold angle, the prosthetic arm performs the grasping and ungrasping function.