CAJ | 학술논문

提出一种直线超声电动机驱动的平面3-PRR并联平台，研究并联平台视觉精密定位技术。给出并联平台结构并采用矢量链法得到并联平台运动学模型。针对并联平台动平台位姿测量问题，利用视觉系统作为反馈单元，通过图像处理技术对动平台上的人工特征中心定位，实现对动平台位姿精确测量；针对传统PID关节控制器在实际控制中问题，采用基于扰动观测器的并联平台支链控制器模型。试验结果表明：对于目标位置为(20 mm,20 mm)，并联平台半闭环控制精度约为±500μm，而通过视觉定位精度达到±5μm。视觉定位较半闭环控制大幅提高了并联平台定位精度，能够满足并联平台大行程、高精度定位的需求。
제출일충직선초성전동궤구동적평면3-PRR병련평태，연구병련평태시각정밀정위기술。급출병련평태결구병채용시량련법득도병련평태운동학모형。침대병련평태동평태위자측량문제，이용시각계통작위반궤단원，통과도상처리기술대동평태상적인공특정중심정위，실현대동평태위자정학측량；침대전통PID관절공제기재실제공제중문제，채용기우우동관측기적병련평태지련공제기모형。시험결과표명：대우목표위치위(20 mm,20 mm)，병련평태반폐배공제정도약위±500μm，이통과시각정위정도체도±5μm。시각정위교반폐배공제대폭제고료병련평태정위정도，능구만족병련평태대행정、고정도정위적수구。
A 3-PRR planar parallel manipulator actuated by liner ultrasonic motor is set up and investigated. The structure of the planar parallel manipulator (PPM) is presented, and then the kinematic model of the manipulator is developed based on vector chain method. To realize the global closed-loop feedback, charge coupled device camera is adopted to measure the output of the manipulator, namely the 3 degrees of freedom of the manipulator. By using the technologies of image processing, the center of the artificial features fixed on the moving platform is located to realize the pose measurement of the moving platform. A perturbation observer-based joint control is adopted to overcome the disadvantage of the traditional PID control in real time control. Experimental results show that the accuracy of the semi-closed loop control of the PPM is around 500 μm while the target position is (20 mm,20 mm), but after the procedure of the visual based closed loop control, the positioning accuracy is further improved to ±5 μm. Compared with the semi-closed loop control, the visual based positioning control provides a substantial increasing in positioning accuracy of the PPM, which could satisfy the positioning requirements of the PPM.