具有控制力约束的全方向步行器可靠跟踪控制  

Reliable tracking control for omnidirectional walker with control force constraint

作　　者：孙平[1] 周晓舟[1] 

机构地区：[1]沈阳工业大学信息科学与工程学院,沈阳110870

出　　处：《沈阳工业大学学报》2015年第4期446-450,共5页Journal of Shenyang University of Technology

基　　金：辽宁省高等学校优秀人才支持计划项目(LJQ2014013)

摘　　要：全方向步行器在实际使用过程中某个执行电机不可避免地会发生失效,从而影响训练者的安全,针对这一问题,研究了全方向步行器的可靠跟踪控制.基于冗余自由度思想,采用分离故障执行器的方法,利用无故障执行器实现康复者的安全跟踪训练.通过构造Lyapunov函数,保证了跟踪误差系统在全局坐标系下的渐近稳定性,结合双曲正切函数得到控制力约束型可靠控制器的表达形式.仿真结果表明,当某个执行器发生故障时,所设计的控制器能实现步行器的稳定运行,保障了康复者的安全.A certain actuator motor may lose their effectiveness inevitably during the actual applications of an omnidirectional walker, which will affect the safety of trainers. Aiming at this problem, the reliable tracking control of the omnidirectional walker was studied. Based on the redundant freedom degree idea, the faultless actuators were used to realize the safety tracking training of convalescents by separating the fault actuators. Through establishing the Lyapunov function, the asymptotic stability of error tracking system could be ensured in the global coordinate system. In combination with the hyperbolic tangent function, the expression form of reliable controller with the control force constraint was obtained. The simulated results show that when the malfunction appears for a certain actuator, the proposed controller can realize the stable operation of the walker and ensure the safety of the convalescents.

关 键 词：全方向步行器 失效 可靠跟踪控制 冗余自由度 LYAPUNOV函数 渐近稳定 双曲正切函数 控制力约束 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]