A hardware–software system for coordinated multi-axis control based on a non uniform rational B-splines interpolator applied to industrial computer numerically controlled machines

Abstract

Motion controllers are widely used in many mechatronic applications such as computer numerically controlled machine tools and robots. These applications demand the use of high performance controllers. Some desirable characteristics in motion controllers are coordinated multi-axis control, smooth movements, and advanced interpolation methods. An important manufacturing aspect involves the production of a workpiece in a free form or using the parametric surfaces in modern computer aided design/computer aided manufacturing systems. The use of parametric curves and surfaces has become standard due to their ability to represent objects having complex surfaces with less data. Another mandatory characteristic of motion controllers is the real-time operation. The contribution of the present work is the design and implementation of a hardware–software system for multi-axis motion control featuring non uniform rational B-splines interpolation. Advantages over other reported works are the hardware implementation which allows the application to real computer numerically controlled machines; also the parallel processing permits the incorporation of additional modules to form an integral system without dependence on external devices. Two experiments were carried out in a retrofitted-to-computer numeric control milling machine in order to show the efficiency of the developed system.