Error compensation of free-form surface with critical area based on T-spline surface reconstruction

In this study, a novel method for error compensation of free-form surface with critical area is investigated. With the proposed method, the machining accuracy of the surface can vary from area to area according to the precision requirement. The local refinement of the T-spline surface is used to set more sampling points in the critical area. A compensate surface is constructed according to the on-machine measurement data to improve the machining accuracy of the surface. Simulation result shows that the T-spline surface has better fitting accuracy compared with the NURBS surface, given the same coordinates information of the surface. Verification experiments showed that the mean machining error of the normal area is improved by 62.1%, while the mean machining error of the critical area is improved by 73.9%.