Title
Reinforcement Learning Assist-As-Needed Control For Robot Assisted Gait Training
Abstract
The primary goal of an assist-as-needed (AAN) controller is to maximize subjects' active participation during motor training tasks while allowing moderate tracking errors to encourage human learning of a target movement. Impedance control is typically employed by AAN controllers to create a compliant force-field around the desired motion trajectory. To accommodate different individuals with varying motor abilities, most of the existing AAN controllers require extensive manual tuning of the control parameters, resulting in a tedious and time-consuming process. In this paper, we propose a reinforcement learning AAN controller that can autonomously reshape the force-field in real-time based on subjects' training performances. The use of action-dependent heuristic dynamic programming enables a model-free implementation of the proposed controller. To experimentally validate the controller, a group of healthy individuals participated in a gait training session wherein they were asked to learn a modified gait pattern with the help of a powered ankle-foot orthosis. Results indicated the potential of the proposed control strategy for robot-assisted gait training.
Year
DOI
Venue
2020
10.1109/BioRob49111.2020.9224392
BioRob
Keywords
DocType
ISSN
Assist-as-needed controller, robot-assisted gait training, reinforcement learning, wearable robotics, rehabilitation robotics
Conference
2155-1782
Citations 
PageRank 
References 
0
0.34
0
Authors
4
Name
Order
Citations
PageRank
Yufeng Zhang111730.05
Shuai Li200.34
Karen J. Nolan313.81
Damiano Zanotto45512.02