Abstract
There have been many researches on the contouring control for machine tool feed drive systems. To the best of authors' knowledge, its effectiveness has been shown only by comparative experiments with industrial non-contouring (independent axial) controllers that are previously set up, or non-contouring controllers along with the contour error compensator such as the cross-coupling controller. Because the control performance largely depends on controller gains, such comparison remains some ambiguities to show the effectiveness of contouring control. In other words, a similar control performance may be achieved if the non-contouring controller gains are appropriately assigned. This paper discusses the effectiveness of contouring controller in both analytical and experimental manners. A basic formulation of a coordinate transformation based contouring controller and its effectiveness are shown. Because there exists an inherent contour error in the coordinate transformation approach, a method to reduce the inherent contour error is presented to enhance the effectiveness of contouring controller. The contouring controller is concluded to be effective, in that it provides a comparative performance to the non-contouring controller with less control input variance. This property seems to be useful for not damaging machine tool systems, and for saving required control energy.
