Study on Modeling Method of the Precision Machined Surface Geometry form Error Based on Bi-Cubic B-Spline

For precision mechanical system, the different 3d spatial distribution of form error causes different assembly contact state. Since 3d spatial distribution of form error is not taken account in modeling and evaluation method of geometric form error and it is hard to quantitatively analyze the relationship between form error and assembly accuracy of precision mechanical system, a modeling method of machined surface form error based on bi-cubic B-spline surface reconstruction is proposed. Firstly, a reconstruction algorithm of CMM date based on bi-cubic B-spline is proposed, so the mathematical model of the surface form error is established. Then, the data transaction method between Matlab and Pro/E is proposed, and the 3D solid model of parts is established, which has the surface form error. Finally, the validity and reliability of the proposed method is validated by the establishment of the typical mating surfaces form error model.