Torque Control by EMG Feedback in Normal and Stroke Subjects Performing Ankle Angle Tracking with a Rehabilitation Robot

肌電圖回饋作為復健機器人扭矩控制於常人及中風病人踝關節角度追蹤研究

林宙晴(Chou-Ching K. Lin) ； 高聖涵(Sheng-Han Gao) ； 朱銘祥(Shu-Min Chen) ； 程淑敏(Ming-Shaung Ju)

《中國機械工程學刊》 36卷1期 (2015/02) Pp. 21-29

摘要

本文探討表面肌電圖回饋在復健機器人實現踝關節扭矩控制，以應用於常人與中風病人的踝關節角度追蹤訓練。以肌電圖估測受測者主動扭矩的優點在於可直接誘發目標肌肉的扭矩控制。本研究在復健機器人上實現模糊比例積分控制器。首先將每位受測者踝關節固定至5個位置以建構其靜態肌電圖-扭矩關係圖。利用該圖可由脛骨前肌肌電圖內插腳踝背屈主動扭矩。實驗中同時擷取肌電圖及扭矩感測器之輸出，並以肌電圖內插扭矩和扭矩感測器輸出之權重和控制踝關節機器人；權重由0至1間隔0.25。本研究共招募6位常人及7位中風病人進行追蹤實驗，追蹤軌跡為速度每秒3度之背屈及蹠屈的往復動作。結果顯示：所有的肌電圖內插扭矩和感測器輸出的權重和都能做為機器人扭矩控制之回饋訊號。常人比中風病人有更好的追蹤性能，且只使用扭矩感測器輸出回饋時，可得到較佳的追蹤性能。

並列摘要

The goal of this study was to investigate the eligibility of using surface electromyography (EMG) as a feedback signal for ankle torque control in both normal and stroke subjects performing ankle joint angle tracking with a rehabilitation robot. The potential advantage of using EMG as an estimator of active torque is direct facilitation of torque control of individual muscle. A fuzzy PD+I controller was implemented to control the robot. A static EMG-torque map was constructed at 5 ankle positions experimentally for each subject. The map was interpolated to estimate the active dorsiflexion torque exerted on the ankle from the EMG of tibialis anterior muscle. Both EMG and the output of the torque sensor were acquired and a weighting factor was used to adjust the relative contribution from these two signals for controlling the robot. Six normal subjects and seven stroke patients were recruited. The angle trajectory to be tracked was alternating ramps (3º/s) of dorsiflexion and plantarflexion. The results showed that all the tested combinations of EMG and the torque sensor signal could be used as the feedback signal for torque control during angle tracking with the robot. The normal subjects had a better performance than the stroke patients and the tracking performance was better when only the signal from the torque sensor was used.

並列關鍵字

Electromyography ； rehabilitation ； robot ； torque control ； angle tracking