Identification and compensation of the deviations inherent to multi-axis machine tools

本研究提出了典型多轴控制机床五轴控制加工中心和多任务车床固有旋转轴几何偏差的两种独特识别方法，以及基于该识别方法的机床坐标校正方法和数控程序。在本研究工作中，根据世界上机床制造商的网站和目录，发现五轴机床的结构配置有24种。配置数少于预期。处理步骤然后，研究了五轴控制机床存在偏差的确定方法。对现行标准ISO10791-1中规定的通用主轴头五轴加工中心的误差测量方法进行了详细的研究。设计了一种用滚珠杆测量三轴（包括一个旋转轴）同时控制圆弧插补运动轨迹的方法。提出了用一些表达式计算轨迹偏心量对五轴控制加工中心的特殊偏差的方法。利用球杆测得的轨迹偏心率值，可以确定几何偏差。此外，由于使用识别值进行了校正，因此证明可以获得高精度的轨迹。在此基础上，研究了采用四轴同步控制运动的方法识别误差。特别是，这种测量方法的优点在于，尽管在三轴控制运动中需要进行四次测量，但所有的偏差都可以从两个测量轨迹中识别出来。结果表明，用该方法识别的偏差与三轴控制测量具有相同的精度。少

This research work has developed two unique methods for identifying geometrical deviations that related to the rotary axes inherent to five axis control machining centers and multi-tasking turning machines, those were typical multi-axis control machine tools, and also the method for correcting the machine coordinate and the NC program based on the identification method.In this research work, it was found that there were 24 structural configurations in the five-axis machine tools according to the websites and catalogues of the machine tool builders in the world. The number of the configurations is less than the number expected.Then, the method for determining the deviations those existed in the five axis control machine tools was investigated. The measuring methods of the deviations of 5-axis machining centers with a universal spindle head specified in the present standard ISO10791-1 were precisely investigated. The method of measuring the trajectory of the circular interpolation moveme … More nt when three axes including one rotary axis were simultaneously controlled was designed by means of a ball bar. The method of calculating peculiar deviations to the five axis control machining center from the amount of eccentric of trajectory was proposed by using some expressions. It is possible to identify the geometric deviations by using the values of eccentricity of the trajectories measured by the ball bar. In addition, it was proven to be able to obtain highly accurate trajectories since the correction was tried by using the identification values. Moreover, the method of identifying the deviation by using simultaneous four-axis control movement was investigated. Especially, this measuring method is excellent in the point that all the deviations can be identified from two measured trajectories only, although four measurements are necessary in the three-axis control movement. It was clarified that the deviation identified by using this method gives same accurate as the three axis control measurement. Less