Dynamic compliance attenuation in ball screw drives through model-based active damping of multiple vibration modes

Abstract

This paper presents a new control structure for ball screw drives (BSDs), which achieves position tracking through an outer loop, and active vibration damping for dynamic stiffness enhancement through an inner loop based on H2-synthesis. As an advancement over earlier BSD control methods with active damping, the proposed technique is able to consider multiple vibration modes simultaneously, rather than only the most dominant (axial) vibration mode. The end result is 2–3 times reduced dynamic compliance over a wide frequency range, compared to approaches like P-PI position-velocity cascade control (industry standard) and pole-placement control (PPC), and comparable or better tracking accuracy.