Dynamic analysis of a gas bearing support guide way through simplified beam model

This paper presents a dynamic analysis of ultra precision gas bearing linear motion system through a simplified spring-spring support beam subject to force and toque excitation. H type ultra precision position gas bearing linear motion stage with 2DOF is one type of extensive use ultra precision position stage, its X glide way is support by two air bearing at two end and support a payload stage through linear motor. Due to the center of gravity and the center of drive force can’t be on line precisely, X glide and payload stage will vibrate when acceleration or deceleration, that’s will harm to the control system. In order to solve this problem, this glide way is be simplified to a spring-spring support Euler-Bernoulli beam, pitch of payload is be simplified to a torque, free vibration analysis and forced response of torque excitation of beam are proceeded on the basis of mechanics of elasticity. Then the solution of spring-spring beam with concentrated damping and distributed damping is given, some numerical results are shown to present the effects of different support stiffness and section dimensions.