五轴联动机床的动态性能不仅取决于各单轴伺服进给系统动态特性，各轴之间的动态特性是否匹配也对其有着显著影响。该文针对具有刀具绕中心点旋转（RTCP）功能的AC型双摆头五轴联动铣床，提出了一种通过圆度测试法进行多轴间伺服匹配以提高机床整体动态精度的优化方法。该方法在选取了合理的匹配对象后，可在有效降低用于搭建各单轴机电耦合系统成本的同时保证系统较高的整体动态精度。首先基于该装有AC双摆头的五轴联动铣床的整体结构进行机构运动学分析，基于机床整体结构对其各轴伺服进给系统进行机电耦合建模并在SIMULINK中搭建各轴模型；接着基于RTCP功能设计了一条多轴参与运动的特定轨迹，对各轴在该运动轨迹下的运动关系进行分析；通过合理选择匹配对象，基于圆度测试法对X、Y、Z三轴两两轴间进行伺服匹配；而后基于SIMULINK模型，对优化前后机床在特定轨迹下运动的整体动态性能进行仿真对比。结果表明：在该优化方法下，几乎不需要提高伺服进给系统搭建成本，系统就可达到较高的整体动态性能。
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.
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