Department of Physiology, University of Alberta, Edmonton, Canada.
IEEE Trans Neural Syst Rehabil Eng. 2011 Dec;19(6):601-11. doi: 10.1109/TNSRE.2011.2166405. Epub 2011 Oct 3.
Electromechanical delay (EMD) is a biological artifact that arises due to a time lag between electrical excitation and tension development in a muscle. EMD is known to cause degraded performance and instability during neuromuscular electrical stimulation (NMES). Compensating for such input delay is complicated by the unknown nonlinear muscle force-length and muscle force-velocity relationships. This paper provides control development and a mathematical stability analysis of a NMES controller with a predictive term that actively accounts for EMD. The results are obtained through the development of a novel predictor-type method to address the delay in the voltage input to the muscle. Lyapunov-Krasovskii functionals are used within a Lyapunov-based stability analysis to prove semi-global uniformly ultimately bounded tracking. Experiments on able-bodied volunteers illustrate the performance and robustness of the developed controller during a leg extension trajectory following task.
机电延迟（EMD）是一种生物伪影，它是由于肌肉中电兴奋和张力发展之间存在时间滞后引起的。EMD 已知会导致神经肌肉电刺激（NMES）期间性能下降和不稳定。由于未知的非线性肌肉力-长度和肌肉力-速度关系，补偿这种输入延迟变得复杂。本文提供了一种具有预测项的 NMES 控制器的控制开发和数学稳定性分析，该预测项主动考虑了 EMD。通过开发一种新的预测器类型方法来解决肌肉电压输入的延迟，从而获得结果。Lyapunov-Krasovskii 泛函在基于 Lyapunov 的稳定性分析中用于证明半全局一致最终有界跟踪。对健全志愿者的实验说明了在腿部伸展轨迹跟踪任务中，开发的控制器的性能和鲁棒性。
