Research of Performance Comparison of Topology Structure of Cross-Spring Flexural Pivots

Cross-Spring Flexural Pivot (CSFP) has some advantages compared with rigid bearing. However, this kind of flexural pivot is limited in the field of precision positioning due to its small motion stroke, large axis drift, and sensitivity to temperature, etc. In this paper, topology structures of the CSFP were analyzed through defining different geometric parameters λ, spring crossing angle α, and spring number N. Characteristics of stiffness, axis drift, maximum stress, and temperature drift were compared and summarized by the Finite Element Analysis (FEA). Ultimately, a class of flexural pivots, called Inner and Outer Ring Flexural Pivots (IORFP), were selected for their excellent comprehensive performances. This type of flexural pivots has some significant advantages, such as large stroke, approximate zero axis drift and no temperature drift. Finally, the stiffness characteristic of IORFP with different geometrical parameters λ was compared by FEA, and law of stiffness variation was obtained. When λ is 0.1273, the IORFP has linear stiffness characteristics.