Abstract: As a new kind of mechanisms, the compliant mechanism accomplishes the transmission or transformation of motion, force and energy by the elastic deformation of component itself. It is an advanced aspect in the study of the mechanisms. A new dynamic model of compliant links with different loads (end moment or vertical force) is proposed based on 2R pseudo-rigid-body model (PRBM). The kinetic energy and deformation energy are obtained based on the new dynamic model. The dynamic equations of compliant links are derived via Lagrange equation. Compared with the 1R pseudo-rigid-body dynamic model (PRBDM), the equation property and dynamic response of each pseudo-rigid-body dynamic model are analyzed. The superiority of the 2R pseudo-rigid-body dynamic model is presented. The validity of the new model is verified in the example of a planar compliant parallel-guiding mechanism. The numerical results indicate that not only the motion trend but also the internal local deformation of compliant links are described in the 2R pseudo-rigid-body dynamic model. The 2R pseudo-rigid-body dynamic model can be used to show the dynamic behavior of compliant mechanisms and is suitable for the dynamics analysis and design of compliant mechanisms.

Key words: 2R pseudo-rigid-body model, Compliant mechanisms, Dynamics