Abstract: There are a series of technical problems in the application of the aerostatic motorized spindle to meet the requirements of ultra-high speed and ultra-precision machining, such as electromagnetic losses of high frequency motor, eccentric electromagnetic excitation, high harmonic excitation, thermal effects and inertial effects caused by motor high speed running. Therefore, it is necessary to make systematic analysis and intensive review on the factors which influence the dynamic characteristics of aerostatic motorized spindle. The retrospection of the development history and status of the aerostatic motorized spindle is presented. The effects of critical factors on the stability of high speed motorized spindles are analyzed and commented from the aspects of aerostatic bearing structure, gas flow forms, eccentric electromagnetic excitation and unbalance response, then the influences of bearing type, bearing parameters optimization, surface roughness and journal inclination on the system stiffness are summarized. The effects of critical speed, speed-torque characteristics on the high speed performance and its byproducts of thermal effects and gas inertia are analyzed in detail. The principle factors that influence the rotation accuracy, the mechanism of rotation erro informaticion, the accuracy text and error separating technique are commented. Finally the development tendency of the aerostatic motorized spindle technology is predicted.

Key words: Aerostatic bearing, High speed spindle, Motorized spindle, Ultra-high precision