On acceleration/deceleration hybrid interpolation for multi-blocks of NURBS curves

In general, there are two types of acceleration/deceleration (Acc/Dec) motion planning architectures: Acc/Dec before interpolation (ADBI) and Acc/Dec after interpolation (ADAI). The ADBI approach will not generate command errors and the look-ahead function can be easily implemented. The ADAI approach can generate smooth velocity profiles even at sharp corners. In this paper, a novel Acc/Dec hybrid interpolation (ADHI) scheme is presented. The ADHI integrates the ADBI and ADAI techniques to deal with multiblocks of non-uniform rational B-spline (NURBS) curves. The feedrates for multi-blocks of NURBS curves are computed by utilizing the derived corner error equation. Simulations are performed to validate the ADHI approach. It is shown that the ADHI approach improves tracking and contour accuracies significantly compared to the hybrid multi-blocks look-ahead approach.