Nonlinear deformation behavior of a beam-based flexural pivot with monolithic arrangement

Manufacturing the cross-spring pivot is not an easy task because of the non-monolithic arrangement. This problem can be resolved by moving the intersection point of the pivot to a remote position. However, the in-plane configuration leads to nonlinear behavior for the monolithic flexural pivot. In this paper, the nonlinear models of stiffness and center shift are developed for parametric insight of the large deformation behavior. The influences of both two drive loads (the horizontal force and bending moment) on the rotational stiffness are characterized, and the load stiffening effect induced by the payload is analyzed. Meanwhile, the nonlinear relationships between center shift and angular displacement are investigated to provide reference for combination of the building blocks. In addition, the effect of loads on the center shift is also evaluated, which is an important consideration in the design of compliant mechanisms. Finally, the nonlinear characteristics, revealed by the analysis model, are validated by finite element analysis (FEA).