Robotic exoskeletons are expected to show high compliance and low impedance for human–robot interactions (HRIs). Our study introduces a novel method based on nonlinear model reference adaptive control (MRAC) to reduce the inherent impedance and replace the traditional impedance controller in HRIs. The control law and adaptive law are designed according to a candidate Lyapunov function. A simple system identification and initialization method for the nonlinear MRAC is put forward, which provides a set of better initial values for the controller. From the results of simulation and experiment, our controller can reduce the mechanical impedance and achieve high compliance for HRI. The adaptive control and compliance control can be both achieved by the proposed nonlinear MRAC framework.

中文翻译：

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基于非线性模型参考自适应控制的新型外骨骼系统阻抗控制器

机器人外骨骼有望在人机交互 (HRI) 中表现出高顺应性和低阻抗。我们的研究引入了一种基于非线性模型参考自适应控制 (MRAC) 的新方法，以降低 HRI 中的固有阻抗并取代传统的阻抗控制器。根据候选 Lyapunov 函数设计控制律和自适应律。提出了一种简单的非线性MRAC系统辨识和初始化方法，为控制器提供了一组较好的初始值。从模拟和实验的结果来看，我们的控制器可以降低机械阻抗并实现 HRI 的高顺应性。自适应控制和顺从控制都可以通过提出的非线性 MRAC 框架来实现。