Some aspects of the application of closed loop servo systems to machine tool control

The paper discusses the combined design of machine tool and control equipment with particular reference to a two-axis profile follower system. The power requirements of the feeds are reviewed and in particular the effects of calling for excessive power on motor size and on motor torque/inertia ratio and hence overall servo system performance. The associated problems of ¿backlash¿ and ¿stiction¿ and the effects of these factors on the performance of the system as a whole are considered. The effects of the general rigidity of the machine tool itself, questions of vibration and of dragging of the stylus on the model of template are also examined. To illustrate the effects of the various mechanical factors on system performance, typical electronic copying systems are briefly described.