Page 68 - Read Online

Yang et al. Intell Robot 2024;4(1):107-24 Intelligence & Robotics
DOI: 10.20517/ir.2024.07

Research Article Open Access

Coordinated energy-efficient walking assistance for
paraplegic patients by using the exoskeleton-walker
system

Chen Yang, Xinhao Zhang, Long Zhang, Chaobin Zou , Zhinan Peng, Rui Huang, Hong Cheng
School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan, China.

Correspondence to: Dr. Chaobin Zou, School of Automation Engineering, University of Electronic Science and Technology of China,
No. 2006, Xiyuan Ave, West Hi-Tech Zone, Chengdu 611731, Sichuan, China. E-mail: chaobinzou@uestc.edu.cn
How to cite this article: Yang C, Zhang X, Zhang L, Zou C, Peng Z, Huang R, Cheng H. Coordinated energy-efficient walking assis-
tancefor paraplegic patients by using the exoskeleton-walker system. IntellRobot2024;4(1):107-24. http://dx.doi.org/10.20517/ir.2024.07

Received: 1 Dec 2023 First Decision: 16 Jan 2024 Revised: 7 Feb 2024 Accepted: 4 Mar 2024 Published: 19 Mar 2024
Academic Editor: Simon X. Yang Copy Editor: Dong-Li Li Production Editor: Dong-Li Li

Abstract
Overground walking can be achieved for patients with gait impairments by using the lower limb exoskeleton robots.
Since it is a challenge to keep balance for patients with insufficient upper body strength, a robotic walker is neces-
sary to assist with the walking balance. However, since the walking pattern varies over time, controlling the robotic
walker to follow the walking of the human-exoskeleton system in coordination is a critical issue. Inappropriate control
strategy leads to the unnecessary energy cost of the human-exoskeleton-walker (HEW) system and also results in
the bad coordination between the human-exoskeleton system and the robotic walker. In this paper, we proposed a
Coordinated Energy-Efficient Control (CEEC) approach for the HEW system, which is based on the extremum seeking
control algorithm and the coordinated motion planning strategy. First, the extremum seeking control algorithm is used
to find the optimal supporting force of the support joint in real time to maximize the energy efficiency of the human-
exoskeleton system. Second, the appropriate reference joint angles for wheels of the robotic walker can be generated
by the coordinated motion planning strategy, causing the good coordination between the human-exoskeleton system
and the robotic walker. The proposed approach has been tested on the HEW simulation model, and the experimental
results indicate that the coordinated energy-efficient walking can be achieved with the proposed approach, which is
increased by 60.16% compared to the conventional passive robotic walker.

Keywords: Exoskeleton robots, robotic walker, energy efficiency, coordinated motion planning

© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0
International License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, shar-
ing, adaptation, distribution and reproduction in any medium or format, for any purpose, even commercially, as long as you
give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate
if changes were made.

www.intellrobot.com