基于摩擦补偿的空间机械臂关节高精度控制研究

Study on High Precision Position Control of Space Robotic Arm Joints Based on Friction Compensation

空间机械臂关节具有大惯量、高精度的特点,针对空间机械臂关节低速、高精度控制要求,提出一种基于摩擦补偿的双位置闭环控制策略。建立了考虑摩擦和惯量变化等因素的一体化关节动力学模型,分析了全位置闭环系统的稳定性,在此基础上提出了一种基于双位置传感器信息的闭环伺服控制策略,并引入自适应率辨识未知摩擦和惯量变化,利用Lyapunov函数证明闭环系统的稳定性和跟踪误差的渐进收敛性。在测试平台上的试验结果表明,提出的空间机械臂一体化关节伺服控制策略能够有效地提高关节伺服控制精度和系统鲁棒性。

An adaptive high precision position control with friction compensation and double-position sensor scheme for Space robotic arm joint was presented .A robotic arm joint was modeled as a cas-cade dynamics system and friction model with nonuniform friction variations was used to characterize the friction force .The stability of double-position sensor close-loop control system was analyzed and nonlinear adaptive control laws were designed to identify the unknown friction , inertia and the exter-nal disturbances .The system stability and asymptotic trajectory tracking performance were guaran-teed by Lyapunov function and demonstrated by the experimental results .