车铣复合加工中心综合误差检测及补偿策略

Comprehensive measurement errors of 5-axis turning-milling centers and their compensation strategies

根据五轴车铣复合加工中心的结构及其运动链构型特点,设计了综合误差检测方案。检测包括车主轴床身至铣主轴运动链的空间误差检测以及车主轴的热误差检测两部分。由于检测方案使刀具-工件之间构成了完整的运动链,解决了单纯的空间误差检测方法未考虑车主轴运动链误差影响的问题。文中同时提出了车铣复合加工中心综合误差补偿策略以及运用神经网络算法的几何误差和热误差综合补偿模型。采用分步体对角空间误差检测后,实施了空间误差补偿。补偿后四条体对角线的空间误差都明显减小,减小幅度从15.24μm到50.83μm,误差补偿效果从39.10%提高到78.06%。本文提出的方法极大地改善了空间误差补偿精度。

A comprehensive error measurement plan was designed based on the structure and characters of the kinematic chain for a 5-axis turning-milling combine machine system to compensate errors.The measurement tests include two parts：the volumetric error between turning main spindle frame and milling spindle and the thermal error of turning main spindle.As the plan combined the tool and the working piece to be a complete kinematic chain,the problem of the turning main spindle chain error effect which was not considered in the single space measurement was solved.The comprehensive error compensation model of geometrical errors and thermal errors were also set up based on artificial neural network algorithm and then the volumetric error was compensated after measurement in body diagonals along three axes.The experiments show that the volumetric errors of four body diagonals are obviously decreased with the values from 15.24 μm to 50.83μm after compensation and the compensation effects have been improved from 39.10％ to 78.06％.The method improves volumetric error compensation accuracy.