CAJ | 학술논문

500 m口径球面射电望远镜(Five hundred meter aperture spherical radio telescope, FAST)的馈源支撑与指向跟踪机构由宏微并联机器人系统构成,大跨度柔索驱动的宏并联机器人保证系统的大工作空间,精密电动缸驱动的Stewart平台作为微并联机器人保证系统的末端精度并扩展其伺服带宽.为了降低宏并联机器人的柔性对末端定位精度的影响,提出基于并联机构学原理的三维机动目标解耦跟踪预测算法,对馈源舱的运动进行跟踪预测.引入自适应交互算法解决PID参数的实时调整,设计自适应交互PID监督控制器,根据馈源舱的预测运动和馈源平台的目标轨迹产生电动缸规划级控制量.此外,在电动缸执行级采用带前馈的数字伺服滤波器实现电动缸的高精度轨迹跟踪.FAST50 m缩尺模型试验表明,结合解耦预测算法对馈源舱的运动预测,自适应交互PID监督控制器效果良好,能够确保宏微并联机器人系统在以期望的跟踪速度运行时,获得完全满足控制要求的定位精度和指向精度.
500 m구경구면사전망원경(Five hundred meter aperture spherical radio telescope, FAST)적궤원지탱여지향근종궤구유굉미병련궤기인계통구성,대과도유색구동적굉병련궤기인보증계통적대공작공간,정밀전동항구동적Stewart평태작위미병련궤기인보증계통적말단정도병확전기사복대관.위료강저굉병련궤기인적유성대말단정위정도적영향,제출기우병련궤구학원리적삼유궤동목표해우근종예측산법,대궤원창적운동진행근종예측.인입자괄응교호산법해결PID삼수적실시조정,설계자괄응교호PID감독공제기,근거궤원창적예측운동화궤원평태적목표궤적산생전동항규화급공제량.차외,재전동항집행급채용대전궤적수자사복려파기실현전동항적고정도궤적근종.FAST50 m축척모형시험표명,결합해우예측산법대궤원창적운동예측,자괄응교호PID감독공제기효과량호,능구학보굉미병련궤기인계통재이기망적근종속도운행시,획득완전만족공제요구적정위정도화지향정도.
The supporting, orientating and trajectory tracking mechanism of the five hundred meter aperture spherical radio telescope (FAST) consists of a macro-micro parallel manipulator system. The macro parallel manipulator (feed cabin) driven by the large span flexible cables assures the large reachable workspace, while the micro parallel manipulator (Stewart platform) driven by the delicate electrical cylinders realizes the precision of the end-effector and expands the servo bandwidth. In order to decrease the impact of the flexibility of the macro parallel manipulator on the precision of the end-effector, a decoupled tracking and prediction algorithm based on the principle of parallel mechanisms is presented. This algorithm is used to predicate the future position and orientation of the feed cabin. Then the adaptive interactive PID controller, which utilizes the adaptive interactive algorithm to adjust the parameters of conventional PID controller, is devised as the supervisory controller in the joint space of the Stewart platform. The supervisory controller generates the control commands in the upper level of the electrical cylinders. Besides, in the lower level of the electrical cylinders, the digital servo filters with feedforward are employed to track the desired trajectory accurately. The experiments of the FAST50 m field model validate the effectiveness of the adaptive PID supervisory controller, accompanied with the motion predication of the feed cabin. The macro-micro parallel manipulator system can obtain the satisfactory positioning and orientating precision with the desired tracking velocity.