Abstract:The performance of a five-axis machine tool not only depends on the dynamic characteristics of each single-axis servo feed system, but also how well the dynamic characteristics of each axis are matched. An optimization method is developed for A/C axes included precision five-axis machine tools with the rotation tool center point (RTCP) function using multi-axis servo matching based on roundness testing to improve the overall machine accuracy. This method uses matched single-axis servo feed systems to reduce the cost of building each single-axis electromechanical coupling system while ensuring the dynamic accuracy. A kinematics analysis of the machine tool structure is used to build an electromechanical coupling model for each axis servo feed system that is implemented in SIMULINK. Then, a specific trajectory is designed for the RTCP function to analyze the motion relationships for each axis for the trajectory. The method is evaluated by selecting matching single-axis servo feed systems for servo matching between three linear axes of X, Y, and Z based on the roundness test method. The SIMULINK model is then used to compare the dynamic performance of the machine tool before and after optimization for the specific trajectory. The results show that this optimization method improves the machine dynamics with little cost for each single-axis servo feed system.
陈彦羽, 关立文, 常佳豪, 胡蓝, 王林泉. 基于RTCP功能的五轴联动伺服匹配优化[J]. 清华大学学报(自然科学版), 2021, 61(10): 1115-1123.
CHEN Yanyu, GUAN Liwen, CHANG Jiahao, HU Lan, WANG Linquan. Optimization of servo matching for a five-axis machine tool based on the RTCP function. Journal of Tsinghua University(Science and Technology), 2021, 61(10): 1115-1123.
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