MORE | Fall 2020

Variable Impedance Control of the Robotic Ankle Joint

This study introduces a variable impedance controller for implementation in wearable robots. The controller applies a range of robotic damping and stiffness to the coupled human-robot system based on the “user intent.” A wearable ankle robot was used to test this controller, and human experiments were performed to understand and quantify the effects of the controller. Subjects performed a target reaching exercise while the robot provided either constant positive damping or variable impedance. These two conditions could then be compared to analyze the performance of the system in terms of stability, agility, and human effort.