Free-form Two-dimensional Contour Error Estimation Based on NURBS Interpolation

Contouring control is in wide use in the manufacturing industry. To achieve accurate contouring control, accurate control error estimation is necessary. However, for free-form contours, there is a lack of effective algorithms for accurately estimating contour errors. This paper proposes a new algorithm for contour error estimation based on NURBS interpolation (CEEBNI). The reference input points closest to the current position is searched. Based on the NURBS interpolation, certain discrete reference input points are then used to reconstruct the NURBS curve. Finally, the contour error is estimated based on the minimum distance between the current position and this NURBS curve. Simulation results indicate that proposed algorithm gives excellent result in the estimation of the contour error.