A brain-controlled lower-limb exoskeleton for human gait training

作者:Liu, Dong; Chen, Weihai*; Pei, Zhongcai; Wang, Jianhua
来源:Review of Scientific Instruments, 2017, 88(10): 104302.
DOI:10.1063/1.5006461

摘要

Brain-computer interfaces have been a novel approach to translate human intentions into movement commands in robotic systems. This paper describes an electroencephalogram-based brain-controlled lower-limb exoskeleton for gait training, as a proof of concept towards rehabilitation with human-inthe- loop. Instead of using conventional single electroencephalography correlates, e.g., evoked P300 or spontaneous motor imagery, we propose a novel framework integrated two asynchronous signal modalities, i.e., sensorimotor rhythms (SMRs) and movement-related cortical potentials (MRCPs). We executed experiments in a biologically inspired and customized lower-limb exoskeleton where subjects (N = 6) actively controlled the robot using their brain signals. Each subject performed three consecutive sessions composed of offline training, online visual feedback testing, and online robot-control recordings. Post hoc evaluations were conducted including mental workload assessment, feature analysis, and statistics test. An average robot-control accuracy of 80.16% +/- 5.44% was obtained with the SMR-based method, while estimation using the MRCP-based method yielded an average performance of 68.62% +/- 8.55%. The experimental results showed the feasibility of the proposed framework with all subjects successfully controlled the exoskeleton. The current paradigm could be further extended to paraplegic patients in clinical trials. Published by AIP Publishing.