2R欠驱动平面柔性机械臂的位置控制策略与试验研究

Position Control Strategy and Experimental Research of A 2R Underactuated Planar Flexible Manipulator

针对同时具有被动关节和柔性杆的欠驱动平面机械臂,提出一种简单易行的分段位置控制策略。以2R欠驱动平面柔性机械臂为研究对象,建立机械臂的假设模态动力学模型,分析系统的动力学耦合特性与可控性。通过被动关节处制动器的开闭切换,研究平面柔性机械臂的分段位置控制策略,采用PID方法分别设计各阶段主动、被动关节的控制算法。最后,基于自行开发的欠驱动平面机械臂的试验平台及实时控制系统,完成了2R欠驱动平面柔性机械臂位置控制的试验研究。仿真和试验结果表明,主动关节和被动关节在各阶段都能很好地跟踪目标值,进而实现机械臂的操作任务,验证了所提控制方法的可行性和有效性,以及欠驱动柔性机械臂动力学模型的正确性。

A simple position control strategy in stages is presented for the underactuated planar manipulator with passive joints and flexible links. The assumed mode dynamic model is established of a 2R underactuated manipulator with a second flexible link and a second passive joint. The dynamic coupling characteristics and the controllability of this system are analyzed. The position control strategy of this manipulator is investigated in stages based on the switch of the brake at the passive joint. And the corresponding algorithms of both the active and passive joints are designed by using the PID method. Finally, on the basis of a self-designed experimental setup of an underactuated planar manipulator, the position control of this 2R underactuated planar flexible manipulator is experimentally completed. The simulative and experimental results illustrate that the active and passive joints can track the targets perfectly in respective stage and the operational task of this manipulator can be implemented, which verify the effectiveness of the proposed method and the correctness of the dynamic model of the underactuated flexible manipulator.