SERVO-DRIVE SYSTEMS FOR MILLING MACHINE RETROFIT APPLICATION

The objective of this paper is to describe how to retrofit a tradition al milling machine, which has the hand wheel-manipulated ladder lead s crew transmission system, with a d.c. servo-drive system. In this rese arch, a d.c. servomotor is used as the actuator instead of the hand wh eel to operate a milling machine table. A PC/AT is used to handle the data acquisition and the control signal calculation for various types of motion condition. The control laws are designed and written as C la nguage software programs. In order to reduce the cost of the approach given in this study, the new type of low-cost PWM motor driver, and po sition and velocity feedback circuits are all designed and implemented . Additionally, a classical PID control method with relay adjustment i s used to design the controller for this converted system in order to verify the approach availability. Finally, the system output response and the controller performance are investigated based upon the experim ental data of this milling machine system operating in different speci fied motion situations.