光学 精密工程, 2019, 27 (1): 51, 网络出版: 2019-04-06
基于后验误差拟合的角位移测量误差补偿
Error-compensation of angular displacement measurement based on posteriori error fitting
光电编码器 后验误差拟合 误差补偿 长周期误差 短周期误差 photoelectric encoder posteriori error fitting error-compensation long period error short period error
摘要
在航天、**、工业这些对器件的体积有着严格要求的领域, 光电编码器不仅要求减小外径尺寸和重量, 更要提高其测量精度。本文以光电编码器误差补偿方法为研究对象, 基于后验误差拟合方法确定误差模型参数, 从而实现对小型光电编码器的深度误差补偿。分析了影响光电编码器测角误差的主要因素, 建立了长周期误差和短周期误差模型。然后, 采用后验误差拟合算法实现了对误差模型参数的确定, 提出误差补偿算法; 最后, 对某一小型光电编码器进行实验, 验证了所提出误差补偿算法的性能。某型号光电编码器补偿前的精度为22.48″, 补偿后的精度为5.82″。实验表明, 采用后验误差补偿方法可以不考虑误差影响因素的大小, 直接对编码器进行误差补偿, 具有效率高、补偿准确等优点, 极大地提高了批量生产时光电编码器产品的精度。
Abstract
In the aerospace, military, and industrial fields, which have strict requirements on the volumes of devices, photoelectric encoders require not only a reduction in the size and weight of the outer diameter, but also improvements in the measurement accuracy. In this study, an error compensation method for photoelectric encoders was investigated. The error model parameters were determined based on a posteriori error-fitting method, and then depth error compensation was performed for a small photoelectric encoder. First, the main factors that affect the angle measurement error of the photoelectric encoder were analyzed, and the long-and short-period error models were established. Then, a posteriori error-fitting error compensation algorithm was proposed. Finally, a small photoelectric encoder was tested to verify the performance of the proposed error compensation algorithm. The test results demonstrate that the proposed posteriori error-fitting compensation method can significantly reduce the angle measurement error of the photoelectric encoder. We utilized an encoder to verify this method. The accuracy before compensation is 22.48″, and that after compensation is 5.82″. This approach employs a posteriori error compensation method, which can directly compensate the encoder error without considering the sizes of the error factors, and possesses the advantages of high efficiency and accurate compensation. The product precision is considerably improved when the photoelectric encoder is mass produced.
于海, 万秋华, 赵长海, 卢新然, 杜颖财. 基于后验误差拟合的角位移测量误差补偿[J]. 光学 精密工程, 2019, 27(1): 51. YU Hai, WAN Qiu-hua, ZHAO Chang-hai, LU Xin-ran, DU Ying-cai. Error-compensation of angular displacement measurement based on posteriori error fitting[J]. Optics and Precision Engineering, 2019, 27(1): 51.