Joint Torque Analysis for Humans in Underwater Environment with Parallel Wire Driven Systems

Abstract

We propose a new method to estimate joint torque of human arms in underwater environment. In the proposed method, a parallel wire driven system drives an end point of a subject's arm to measure the end-point force, and joint torque is estimated with the measured end-point force and the subject's limb length. Since the force sensors with wire used in this system is small enough, the measured torque can be gained under less influence of hydrodynamics on the sensors. We verify the accuracy of the estimation method experimentally and confirm that the proposed method can estimate joint torque of a human arm. We compare the joint torque data of the same trajectory in the different environment and extract the effect of hydrodynamics on human motions in underwater environment.