Safe Guidance for a Walking-Assistant Robot Using Gait Estimation and Obstacle Avoidance

Abstract

This paper presents a motion control design for a walking-assistant robot by combining passive-compliant behavior and active obstacle avoidance. The proposed method recognizes the intended motion for a user using gait movement and the applied force of a hand. A passive-compliant motion control is developed that allows the user to safely walk with the robot. The obstacle avoidance controller actively controls the velocity to guide the user in a direction that avoids collisions. A shared-control scheme combines active obstacle avoidance and passive-compliant motion commands. The experimental results verify the effectiveness of the proposed method and show that the robot allows a user to walk safely in a complex environment. A questionnaire survey of elderly users shows that the proposed design for a walking-assistant robot gives satisfactory performance.