A novel EMG-free prosthetic interface system using intra-socket force measurement and pinch gestures

Abstract

In this paper, we present a novel system to drive a robotic prosthetic hand through the measurement of intra-socket pressure, and gesture selection from the healthy hand. A prototype HRI interface was implemented and used to compare the proposed method with standard state of practice. Grip-selection was made using finger pinch-gestures, was shown to have adequate functionality to provide a user with on-the-fly grip determination and functionality consistent with commercial systems. A moving average filter acting as a signal classifier was created to determine "open" vs "close" patterns sensed by the socket mounted piezo-resistive sensors. Sample windows were user defined as were thresholds used to determine the subject's intent. The subject was able to successfully switch between three predetermined grip configurations of a Touch Bionics i-Limb robotic hand and choose appropriate opening and closing actions.