Optimal design of a micro-positioning Scott-Russell mechanism by Taguchi method

In this paper, main features in kinematics of a micro-positioning Scott-Russell (SR) mechanism associated with two flexure hinges are its displacement amplification and straight-line motion, which are widely needed in practical industries. Without increasing the radial displacement, the SR mechanism is optimally designed by Taguchi method to obtain a maximum amplification of a small displacement driven by a lead zirconate titanate (PZT) actuator. According to kinematic characteristics of the SR mechanism the control factors include the direction, radius, width and offset of flexure hinges. It is found that the directions and offsets of flexure hinges have obvious effects on the amplifying factor and linearity ratio. The software ANSYS is utilized to obtain the numerical simulations, which are compared with the experimental results for the SR mechanism with and without offset of flexible hinges. Finally, some conclusions about the effects of control factors on the performance of the SR mechanism are drawn.