A new methodology for developing flexure-hinged displacement amplifiers with micro-vibration suppression for a giant magnetostrictive micro drive system

Abstract

Flexure-hinged displacement amplifiers play an important part in ultra-precision engineering due to their advantages of no friction, no backlash, compactness, high resolution and so on. In fact, the flexure-hinged displacement amplifier is initially proposed for addressing the travel shortcoming of piezoelectric or magnetostrictive actuators. However, some new challenges such as micro-vibration isolation and long service life, etc., arouse attentions especially when working in the harsh environment. Therefore, a new methodology for designing amplifier which could handle such issues is proposed and discussed in this paper. The focus of this study is on the design, theory analysis, and optimization of amplifiers, not only with the purpose of providing a larger displacement output, but also achieving micro-vibration isolation in desired frequency band. First, a generalized model for flexure hinges, the largest principal tensile stress and fatigue safety factor are formulated mathematically under combined tension and bending loads. Then the applied loads acting on each flexure hinge is calculated according to pseudo-rigid-body model. The equivalent dynamic model is established by Lagrange method. Whereafter, the procedure of the methodology is summarized and a different optimization strategy is implemented. Finally, a prototype is fabricated and tested. The experiments and simulation results confirm that the amplifier can achieve the desired amplification ratio and passive vibration isolation, which validate the effectiveness of this methodology.