Algorithm for NURBS Interpolation Based on Piecewise Feed-Rate Planning

In order to improve efficiency of parameter curve or surface machining, NURBS interpolation algorithm is proposed based on piecewise feed-rate planning. NURBS curve is initially dispersed into micro lines segmentations by uniform error method. With constraint of kinematic characters of machine tool, NURBS curve is divided into curve segmentations and feed-rates are planned in these segmentations, then feed-rate transitions of discrete points of adjacent segmentations are processed and interpolation points are determined according to feed-rates of discrete points, interpolation cycle and chord error. Based on these, NURBS curve interpolation based on piecewise feed-rate planning is implemented. Experimental result indicates that the proposed algorithm is feasible and effective.