【摘要】 针对直角坐标系下球体形状的误差评价,介绍一种利用最小外接球法评价球度误差的计算方法。建立基于直角坐标系下的球度误差三维评测模型,并研究外接球体几何曲面关系,得出了利用弦线截交关系快速评价球度误差的理论。利用弦线截交关系构建最小外接球法球度误差评价的"2+1"、"3+1"、"4+1"评价模式统一体,通过两次截交产生的虚拟中心定位,可以准确确定评价点的位置,达到了快速、精确利用最小外接球法评价球度误差的目的。通过分析表明,基于弦线截交关系的最小外接球球度误差评价方法计算效率高、易于实现且具有较高的评定精度,也为球度误差评价提供一种新的方法和思路。更多还原

【Abstract】 Aiming at evaluation of sphericity form error in cartesian coordinates,an evaluation algorithm of sphericity error by using the minimum circumscribed sphere(MCS) is introduced.In order to evaluate sphericity error accurately,a 3D model of measuring and computing based on cartesian coordinates is established,and geometric curved surface character of circumscribed sphere is studied.As a result,the theory of using geometrical symmetry of intersecting chord to quickly evaluate sphericity error is obtained.The evaluation entia of "2+1","3+1","4+1"modes for MCS by intersecting chord relation is constructed.The virtual center location produced through intersecting chord twice can determine the position of evaluation point accurately,which means making the evaluation more accurate and reliable.The analysis data and results indicate that the algorithm has high computing speed and evaluating precision,thus providing a new strategy and means for sphericity form error evaluation.更多还原