虚拟观测法在球杆仪估算机床平动轴 几何误差中的应用

在利用球杆仪辨识数控机床平动轴的几何误差过程中,由于建立的辨识模型中任意位置的参数矢量矩阵为病态矩阵, 致使在求解辨识模型时存在不精确解或者无解的现象。 针对上述问题,提出了一种基于虚拟观测法的岭估计求解辨识模型解 的方法。 以机床的平动轴为研究对象,基于球杆仪测量的杆长数据,将其代入所建立的误差元素与球杆仪杆长变化量之间的映 射关系,并基于虚拟观测法求解出几何误差项的多项式系数。 该方法从病态矩阵的病因来改善辨识矩阵的病态性,进而实现对 各轴相关误差元素的辨识。 仿真以及实验结果验证了辨识方法的正确性,并改善了辨识矩阵的病态性,研究结果为准确辨识机 床几何误差提供了理论依据。

The application of virtual observation method to the estimation of geometric error of machine tool translational axis using ball bar

In the process of using the ball bar to identify the geometric error of the translational axis, the parameter vector matrix at any position in the formulated identification model is an ill-posed matrix, which may result in inaccurate solutions or no solutions in solving the identification model. To address these issues, a method of ridge estimation based on the virtual observation method to solve the identification model solution is proposed. The translational axis of the machine tool is taken as the research object. Based on the rod length data measured by the ball bar, they are substituted into the established mapping relationship between the error element and the change of the ball bar rod length. The geometry is solved by the virtual observation method the polynomial coefficient of the error term. This method improves the ill-condition of the identification matrix from the cause of the matrix. Then, the identification of the error elements related to each axis is identified. Finally, simulation and experimental results show the correctness of the identification method. And the ill-posed of the identification matrix is improved. The results provide the theoretical basis for accurately identifying the geometric errors of the machine tool.