【摘要】 高精度转台在诸多领域有着广泛的应用,为了提高其转台角分度精度,提出了一种高精度角分度转台及其误差修正方法。首先,介绍了转台的结构设计,转台采用了蜗轮蜗杆传动、圆光栅测角的形式,轴承采用了交叉滚柱轴环,圆光栅采用了增量式,对转台的载物台面进行了力学仿真分析,考察了转台的静力学性能及模态特征;然后,利用多齿分度台和自准直仪对转台的测角精度进行了标定,根据标定获得的误差分布规律,采用基于查表的方法进行了误差补偿,对于整度数之间无标定数据的部分,采用线性插值的方法获得了误差修正量,从而建立了完整的0～360°范围内的误差修正量数表;最后,分别利用多齿分度台和十七面体对误差修正效果进行了实验验证。研究结果表明:利用该方法进行误差补偿,测角最大误差由32.12″降低到1.95″;同时,查表法有效修正了测角误差,使转台可以满足实际场合的使用要求。更多还原

【Abstract】 High-precision turntables have a wide range of applications in many fields, in order to improve the indexing accuracy of the turntable angle, a high precision angle indexing turntable and its error correction measurement were proposed. Firstly, the structural design of the turntable was introduced. The form of worm gear drive and round grating for angle measurement was adopted by the turntable. The cross-roller ring was adopted by the bearing, and the incremental type was adopted by the circle grating. The mechanical simulation analysis was carried out for the load table of the turntable, and the static performance and modal characteristics was investigated. Then, the angle measuring accuracy of the turntable was calibrated by using the multi-tooth dividing table and autocollimator. According to the error distribution law obtained by calibration, error compensation was carried out by the method based on lookup table. For the part without calibration data between integral degrees, linear interpolation method was adopted to obtain error correction, so as to establish a complete table of error correction within 0～360°. Finally, the error correction effect was verified by the multi-tooth indexing table and the optical polyhedron. The experimental results show that the maximum error is reduced from 32.12 "to 1.95" by using this method. The method of lookup table corrects the angle measurement error effectively and makes the turntable meet the requirements.更多还原