为了实现500m口径球面射电望远镜(five hundred meter aperture spherical radio telescope,FAST)二级精调稳定平台对馈源舱隔振控制的定位和指向精度,首先提出了基于并联机构学原理的3维机动目标跟踪预测算法,对柔性支撑Stewart平台的基座运动进行跟踪预测.进而,在Stewart平台关节空间设计了自适应交互PID控制器,引入自适应交互算法解决PID参数的实时调整,以适应柔性支撑Stewart平台的参数变化对不同控制参数的需求.采用现代机电系统仿真策略,对柔性支撑Stewart平台隔振系统的动力学与控制问题进行了仿真,结果表明:与传统的PID控制器相比,自适应交互PID控制器大大改善了隔振效果,完全满足隔振目标的要求.
To achieve the required precision in position and orientation for the feeding platform of a 500 m aperture spherical radio telescope(FAST), we employ a tracking-prediction control based on the kinematics theory of parallel mechanisms to track and predict the motion of the flexibly supported base of the Stewart platform. Adaptive interactive PID controllers, which utilize the adaptive interactive algorithm to adjust the parameters of the conventional PID controllet, are developed for controlling the joint space of the Stewart platform. Based on the modem mechatronic system simulation strategy, the simulation of the dynamics and control of the vibration isolation system in a flexibly supported Stewart plat- form vibration is conducted. The results show that the adaptive interactive PID controller has superior effects in vibration isolation control over the canonical PID controllers, and satisfy the specifications for the vibration isolation control.