Development for precise positioning of air bearing stages

In this paper, we propose control approaches for air bearing stages. First, we consider the case in which air bearing system is a linear stage. A control scheme incoporated with eddy current braking is proposed, where two control inputs are introduced to handle the nonlinear air bearing system. Secondly, we consider the case in which air bearing system is a spherical stage. The control scheme involves Kalman filter and optimal control designs. Finally, experimental results are given to further verify the effectiveness of the proposed methods.