Voice coil motor nano stage with an eddy current damper

This paper presents a nano positioning mechanism with flexure hinge and damper. The nano stage represented in this paper consists of a leaf spring guides and the voice coil motor (VCM) since it provides long working range and the control is easy. However, when the leaf spring is used alone, mechanism has very small damping, which reduces the system stability and causes mechanical vibration in positioning. Especially, in measurement system, since the excessive vibration leads the reduction of the system bandwidth, the elimination of the mechanical vibration is very important. In this paper, the simple eddy current brake system is used as a damper. With a proper damping ratio, the transient response is improved and the settling time of the nano stage is shortened. Numerical and experimental results show the validity of the proposed damped flexure hinge stage.