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.

Key words:  high-precision turntable; angle measurement accuracy calibration; circular grating; error correction

LI Zhong-ming, LI Jun-lin, HAN Bing, et al. High precision angle indexing turntable and its error correction［J］.Journal of Mechanical & Electrical Engineering, 2021,38(9):1180-1184.