The Effect of Negative Damping at the Hip Joint During Level Walking: A Preliminary Testing

Abstract

Walking is a fundamental but important activity for independent daily life. We designed an intuitive controller (called negative damping controller) for the elderly to walk more efficiently. The controller behaves as a negative damping for the hip joint to eliminate natural energy dissipation terms and is capable of mimicking the biological torque profile. The primary objective of this study is to evaluate the effects of the controller on the biomechanical and physiological aspects of gait. As a first step, we measured gait parameters and muscle activation levels for a subject during overground walking with and without exoskeleton at self-selected speed. The experimental results show that the negative damping controller has the potential to enable the wearer to walk overground with larger hip range of motion and lower muscle activation: the hip range of motion increased about 21.9% and the average muscle activation levels decreased about 18.0% in rectus femoris and about 23.7% in bicep femoris.

This work was supported by Institute for Information & communications Technology Promotion(IITP) grant funded by the Korea government(MSIP) (No. 2016-0-00452, Development of creative technology based on complex 3D printing technology for labor, the elderly and the disabled).