The adaptive control for retrofit traditional milling machine

One-step-ahead adaptive control with an input nonlinearity strategy is proposed to control the converted system of a traditional milling machine table with a lead screw transmission system. The control plant is a traditional lead screw actuated milling machine table which has been retrofitted with DC servomotor control. This old-fashioned machining table has nonlinear time-varying behavior due to the effects of irregular Coulomb friction of sliding surface and obvious backlash. Experimental results show that the control method has reasonable performance in terms of stability, transient response, tracking, and robustness under the influence of time delay of the simple motor driver and 1 mm backlash of each axis. This controller can overcome the nonlinear effect due to Coulomb friction and construct a stable closed-loop system.< >