High speed contouring enhanced with C2 PH quintic spline curves

This paper presents a c2 pythagorean-hodograph (ph) spline curve interpolator for high speedcontouring applications. with the knot vector and control points given, the c2 ph quintic spline curveis a ``good'' interpolant to the nodal points of the cubic b-spline curve, with the same knot vectorand control points. to generate the c2 ph quintic spline curves, a uniform knot sequence is employed.the s-curve motion planning architecture, with variable feedrate for a planar c2 ph quintic spline curve,is also developed. in particular, c1 cubic feed acceleration/deceleration is imposed on the first and lastph quintic spline segments. several closed c2 ph quintic spline curve contouring tasks, along with asimple position loop controller, were conducted to verify the effectiveness of the proposed interpolationalgorithm. the experimental results were analyzed and discussed. it is found that the proposed cncinterpolator is not only feasible for machining the complicated parametric curves represented in the c2ph quintic spline form, but also yields a satisfactory contouring performance for variable feedrate control.