Tracking Control of Flexible Ball Screw Drives With Runout Effect Compensation

Most machine tools rely on precision ball screw drives to accurately position the workpiece relative to the tool. In terms of the performance of such machines, tracking is one of the most important aspects that significantly affects the machining outcomes. Minimizing tracking errors of a flexible ball screw drive in the presence of runout phenomenon is explained in this paper. To achieve small tracking errors, the flexibility and runout are modeled by a linear parameter varying system. Based on the derived model, gain scheduling tracking controllers with parameter-dependent Lyapunov functions are designed. The efficiency of the designed controllers in minimizing the tracking error, as well as the importance of the runout modeling, is demonstrated on a ball screw drive experimental setup.