Deterministic Design and Dynamic Characteristics of Two Rotational Guide Mechanism for High Precision Applications

摘要

In this paper, we present the mechanical design and dynamic characteristics of a compliant mechanism based two in-plane rotational guide mechanism (2RGM). The devised mechanism is compact and achieves fast steering of a 25 mm aperture mirror. A general routine for configuration design of 2RGM is presented based on the graphical approach. Deterministic design of the guide mechanism comprises in-plane flexure plate with beam flexures accompanied in parallel with an axial flexure. To enhance the dynamic characteristics, optimum flexure plate parameters are acquired via the minimax algorithm. Further, based on finite element analysis natural frequencies and mode shapes are determined. A prototype of the guide mechanism is manufactured using wire electrical discharge machining (EDM). Experiments on the assembled prototype are conducted using hammer tests about both in-plane rotational axes. Comparison of simulation and experimental results give a satisfactory performance and authenticates the design methodology. The key feature of the mechanism is its bandwidth higher than 1000 Hz. Proposed design methodology enables the devised mechanism with excellent in-plane rotational compliance while constraining the remaining degrees of freedom.