Development of JARoW-II active robotic walker reflecting pelvic movements while walking

Abstract

This paper addresses the problem of a novel walking assist scheme considering pelvic movements. Generally, pelvic motion includes pelvic tilt, pelvic rotation, and lateral pelvic displacement. When a human walks, the pelvis is meant to both tilt and rotate. Specifically, rotational movement on the pelvis' transverse plane and tilting movement on its coronal plane are related to stride length and step width in walking and center-of-gravity swaying in the left-and-right direction, respectively. With these considerations, we introduce the innovative design of our second generation assist robotic walker (JARoW-II) for elderly people in need of supervision. And, this paper proposes a pelvic based walking-support control technique employing JARoW-II. By facilitating pelvic movements while walking, we try to enhance and/or maintain ambulatory performances such as stride length. As another important feature, the scheme is realized without use of specific manual controls or additional equipment. In detail, JARoW-II allows to accurately generate both the direction and location of walking movement and the pelvic movement in a way that corresponds to the user's walking steps. In this paper, the implementation details based on the walking-support scheme are explained, and the effectiveness of the scheme by using JARoW-II is verified through extensive experiments in everyday environments.