An Mechatronics Coupling Design Approach for Aerostatic Bearing Spindles

Abstract

In this paper, a new design approach for aerostatic bearing spindles (ABS) is firstly proposed which takes into account of the interactions between the mechanical and the servo subsystems, including the integration of electromagnetic effects, static pressure characteristics, servo control and mechanical characteristics. According to the air bearing design principle, the geometry of the spindle rotor is designed. The fluid software is used to analyze the influence of the bearing capacity and stiffness on the stability of the spindle. The simulation shows when the air film thickness is 12 μm, the bearing has good load carrying capacity and rigidity. In addition, the influence of motor harmonics on the spindle shaft modes is considered to avoid the resonance of ABS, and to ensure ABS anti-interference capability, proper inertia of ABS is calculated and analyzed. Finally, ABS has a good follow-up effect on the servo control and machining performance through the experimental prototype. The electromechanical coupling design approach for ABS proposed in this paper, can achieve a peak value better than 0.8 μm (surface size: 9 mm × 9 mm) and a surface roughness better than 8 nm in end face turning experiments.