提出一种自动检测时栅转台误差、辨识误差模型系数和误差补偿的方法。该系统利用自制的数控控制箱结合嵌入式技术,以高精度的圆光栅作为基准量仪,以双微控制器与上位机为基础,形成双闭环控制结构,实现系统的高精度定位。在对极点8个待定参数和对极内20个待定参数分别进行傅里叶变换的参数辨识,得到辨识误差模型的系数,实现了实时在线误差补偿。实验结果表明,时栅转台的精度达到2.4″,提高了时栅转台标定精度与标定效率。
An automatic measurement method is proposed to measur error time grating turntable, identify parameters of model and compensating error. The system adopts home-made numerical control box combining with embedded technology. The high precision grating is used as reference meter, and the double closed-loop control structure is formed with double micro-controller and PC to achieve high-precision positioning system. The undetermined parameters, 8 on poles and 20 within poles, are identified by the Fourier transform, to obtain coefficients of identifying error model and to realize the real- time online error compensation. Experimental results show that the double closed-loop control system and parameter identification of Fourier transform, can improve the accuracy and the efficiency of calibration, and the accuracy of the time grating turntable is up to 2.4 "