基于自适应滑模控制器的Stewart平台运动轨迹控制的研究  

Research on Stewart platform trajectory control based on adaptive sliding mode controller

作　　者：姚俊[1] 窦颖艳[1] YAO Jun;DOU Yinyan(School of Electronics and Information,Nanchang University of Technology,Nanchang 330044,Jiangxi,China)

机构地区：[1]南昌理工学院电子与信息学院,江西南昌330044

出　　处：《中国工程机械学报》2020年第5期395-399,405,共6页Chinese Journal of Construction Machinery

基　　金：江西省科学技术厅项目(20202BBGL73056);江西省教育科学规划项目(20YB220)。

摘　　要：对Stewart平台的运动轨迹进行准确的控制,有助于提高其工作效率和工作过程的安全性。对此,提出了采用自适应滑模控制器对Stewart平台运动轨迹控制的方法。首先,从Stewart平台的结构分析出发,求取了其各支腿上所受的弹力,通过Stewart平台中上、下平台的角速度计算了其各链接点产生的速度和加速度矢量,并在此基础上推导出了Stewart平台的运动学方程。然后,根据Stewart平台的运动误差,计算出了理想作用力,且设计了针对干扰量的自适应控制律。在滑模面的基础上,设计了用于减少抖动的控制律,通过该控制律构建了自适应滑模控制器,以对Stewart平台的运动轨迹进行控制。最后,利用本文方法和干扰观测控制器,控制Stewart平台按照目标轨迹运动,与干扰观测控制器相比较,本文方法所得的运动轨迹在X,Y,Z轴三个方向上产生的运动误差分别降低了38.64%,25.00%和37.37%。由此表明,本文方法对Stewart平台运动轨迹的控制更具优良的效果。Accurate control of Stewart platform’s trajectory is helpful to improve its work efficiency and safety.In this paper,an adaptive sliding mode controller is proposed to control the motion trajectory of Stewart platform.First of all,starting from the structural analysis of Stewart platform,the elastic force on each leg is calculated,and the velocity and acceleration vectors generated by each link point are calculated through the angular velocity of the upper and lower platforms in the Stewart platform.On this basis,the kinematics equation of Stewart platform is derived.Then,according to the motion error of Stewart platform,the ideal force is calculated,and the adaptive control law for disturbance is designed.Based on the sliding surface,a control law is designed to reduce the jitter,and an adaptive sliding mode controller is constructed to control the trajectory of Stewart platform.Finally,the Stewart platform is controlled to move according to the target trajectory by using the proposed method and the disturbance observation controller.Compared with the disturbance observation controller,the motion errors of the motion trajectory obtained by this method in X,Y and Z axes are reduced by 38.64%,25.00%and 37.37%respectively,which shows that the proposed method has better control effect on Stewart platform motion trajectory.

关 键 词：STEWART平台 滑模面 自适应控制律 自适应滑模控制器 运动误差 

分 类 号：U463[机械工程—车辆工程]