P-PI and super twisting sliding mode control schemes comparison for high-precision CNC machining

Abstract

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On the sliding mode control for precision machining

“…The first one is a typical control loop implemented in a state of the art of commercial CNC (Fig. 4(b)), and the second one is the P-PD cascaded control loop [16] (Fig. 5).…”

“…Super-twisting SMC control algorithm coping with high-precision machining processes was first proposed and addressed by the authors in a previous paper [16]. Later on, the work [17] applied successfully the algorithm to high precision machining in conventional processes in order to deal with friction of the process using rotatory DC motors.…”