面向交互应用的串联弹性驱动器力矩控制方法  

Series Elastic Actuator Torque Control Approach for Interaction Application

作　　者：王萌[1,2] 孙雷[1,2] 尹伟[1,2] 董帅[1,2] 刘景泰[1,2] 

机构地区：[1]南开大学机器人与信息自动化研究所,天津300350 [2]天津市智能机器人技术重点实验室,天津300350

出　　处：《自动化学报》2017年第8期1319-1328,共10页Acta Automatica Sinica

基　　金：国家自然科学基金(61573198)资助~~

摘　　要：对于串联弹性驱动器(Series elastic actuator,SEA)而言,已有方法大都将其弹性组件视为线性弹簧.然而为了追求更高的能量密度,SEA的机械结构越来越复杂,使其控制问题更具挑战性;此外,现有方法均未考虑当SEA应用于交互系统中,其负载端动力学模型会产生剧烈变化的情况.针对这些问题,本文设计了一种面向交互应用的自适应滑模控制方法.具体而言,首先在考虑了非线性SEA输出特性及系统中可能存在的扰动的情况下,描述了SEA系统的动力学方程,并对其进行了分析和变换.在此基础上设计了负载运动观测器和自适应滑模控制器,使得本文方法能够在负载端动力学模型完全未知的情况下完成SEA的力矩控制.最后通过引入辅助系统,对输入饱和的情况进行了有效的处理.通过理论分析证明了闭环控制系统的稳定性及信号有界性,随后的仿真与实验结果也表明了这种自适应滑模控制器良好的控制性能和对不确定性因素的鲁棒性.For series elastic actuator （SEA） systems, most existing methods treat the mechanical component as a linear spring. However, in order to achieve high energy density, mechanical structures of SEAs are becoming more and more complex, which makes the control problem more challenging. Additionally, currently available approaches cannot guarantee the control performance when the payload dynamics changes drastically during the interaction process. To deal with these problems, an adaptive sliding-mode control method is proposed for interaction applications. Specifically, by taking account of nonlinear SEAs and disturbances, the dynamics of SEA systems is uniformly described and transformed. Then, an observer and adaptive sliding mode controller are designed and they work well even in the presence of unknown payload dynamics. Finally, an auxiliary system is designed to deal with the saturation problem. Stability and boundedness of the closed-loop signal is ensured mathematically. Subsequent experiment results also demonstrate that the designed controller is robust against system uncertainties and can achieve a superior performance for SEA torque control.

关 键 词：串联弹性驱动器 力矩控制 人-机交互 自适应滑模控制 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]