摘要
存在外部干扰以及模型参数不精确时,自由漂浮空间机器人(Free-floating Space Robot,FFSR)末端控制精度无法保证且输出力矩将明显增大,针对此问题提出了一种基于干扰观测器的优化控制方法。首先,根据拉格朗日方程和动量矩守恒定律获得了FFSR的动力学方程和运动学方程表达式。而后,基于FFSR名义模型设计SDRE优化控制器,实现输出力矩和输出误差两项指标的最优化。进而,为克服外部干扰以及参数误差引起的模型不确定性,设计非线性干扰观测器对不确定部分进行在线估计,并反馈到控制器输入中,进一步提高机器人末端轨迹跟踪精度。最后,以两自由度的二连杆空间机器人为对象进行Matlab/Simulink仿真。结果表明:当开启干扰观测器时,这里所提方法在末端跟踪精度以及控制器输出力矩这两项指标上均有明显改善。
When there are external disturbances and model parameters are not accurate,the terminal control accuracy of free floating space robot(FFSR)can not be guaranteed and the output torque will increase obviously.To solve this problem,an optimal control method based on disturbance observer is proposed.Firstly,the dynamic and kinematic equations of FFSR are obtained according to Lagrange equation and conservation law of moment of momentum.Then,the SDRE optimal controller is designed based on FFSR nominal model to realize the optimization of output torque and output error.Furthermore,in order to overcome the model uncertainty caused by external disturbances and parameter errors,a nonlinear disturbance observer is designed to estimate the uncertainty on-line and feed back to the controller input to further improve the tracking accuracy of the robot end trajectory.Finally,a two link space robot with two degrees of freedom is simulated by Matlab/Simulink.The results show that when the disturbance observer is turned on,the proposed method can improve the tracking accuracy and the output torque of the controller.
作者
朱敏
陈山
ZHU Min;CHEN Shan(Changzhou College of Information,Jiangsu Changzhou 213164,China;Jiangsu University,Jiangsu Zhenjiang 212013,China)
出处
《机械设计与制造》
北大核心
2022年第11期243-247,共5页
Machinery Design & Manufacture
基金
江苏高校品牌专业建设工程资助项目(PPZY2015C237)研究成果之一。
关键词
外部干扰
自由漂浮空间机器人
干扰观测器
优化控制方法
External Disturbance
Free Floating Space Robot
Disturbance Observer
Optimal Control Method
