工业机器人关节振动的鲁棒扰动观测器双环补偿控制

Research of Robust Disturbance Observer Double-loop Compensation Control for Joint Vibration of Industrial Robotics

针对工业机器人工作过程中执行机构振动现象,利用现代控制理论对其进行抑振。在对机器人负载侧转速波动机理分析的基础上,建立了RV减速机动态角传动误差和啮合摩擦激励的数学模型;以考虑动态角传动误差和摩擦因素影响的伺服电机-RV减速机-负载所构成的机电耦合系统为控制对象,采用内环鲁棒控制+外环扰动观测器的双环控制策略抑制负载侧的转速波动。结果表明:该方法相比PI控制,不仅使机器人在启动阶段能够快速平稳地对指令做出响应,并且克服了时变刚度所引起的控制系统不确定性,使得稳态工作阶段的转速波动得到了明显削弱,降幅近50%。

In view of the vibration phenomenon of the actuator in the working process of the industrial robot,the modern control theories were employed to suppress the vibration of the actuator.Based on the analysis of the speed fluctuation mechanism on the load side of the robot,the mathematical model of RV deceleration dynamic angular transmission error and meshing friction excitation were established.The electromechanical coupling system composed of servo motor,RV reducer and load considering the influence of dynamic angular transmission error and friction factors was taken as the control object,and the double loop control strategy of inner loop robust control and outer loop disturbance observer was used to suppress the speed fluctuation on the load side.The results showed that compared with PI control,the instructions could be responded more quickly and smoothly by robots during the start-up phase,and rotational speed fluctuation was significantly reduced during the steady-state working phase,with a drop of nearly 50%,while this method was employed.