DYNAMIC MODELING AND ANALYSIS OF FLEXIBLE PLANAR PARALLEL ROBOTS

摘要

This paper presents a simple and efficient method based on finite element theory for dynamic modeling of planar flexible-link parallel robots. The constraint conditions of elastic displacements of flexible parallel robots are presented for the first time. The relation between elastic deformations of links and elastic-rigid coupling effects are investigated. The Kineto-Elastodynamics theory in conjunction with Timoshenko beam theory is employed to derive the equations of motion, considering the effects of distributed mass, lumped mass, rotary inertia, shear deformation, bending deformation, lateral deformations and all the dynamic coupling terms. The dynamic behavior resulting from flexibility of links is well illustrated through the numerical simulation. Compared with the results of SAMCEF software simulation, the numerical simulation results show good coherence and confirm the advantages of the method. The links' flexibility is demonstrated to have significant impact on the system performance and stability. The method presented here is applicable to model spatial parallel robots with various kinds of kinematic pairs.