Kinematic And Dynamic Analysis Of Planar Two Degree Of Freedom Redundantly Actuated Parallel Mechanism

Redundant parallel mechanism is an important branch of the parallel mechanism,the redundancy mechanism can completely or partially eliminate the singularity,optimal and distribute driving force, the parallel mechanism has high bearing capacity, high precision and good dynamic characteristics. Therefore, it is of great theoretical and practical significance to carry out the research of redundant actuation parallel mechanism. In this paper, the planar 2-DOF redundant actuation parallel mechanism is studied,and the kinematics,statics and dynamics of the mechanism are analyzed. The main contents of this paper are as follows:Firstly,two kinds of planar 2-DOF redundant actuation parallel mechanisms are proposed, which are 5RRP-RP and 6RRP-UPU. The mathematical models of inverse kinematics of two mechanisms are established. The expressions of the parasitic motion and the kinematic error of the 5RRP-RP parallel mechanism are derived. The influence of structural parameters on the kinematic characteristics of 5RRP-RP parallel mechanism is analyzed. Through the comparison of MATLAB software and ADAMS virtual prototype simulation software, the correctness of the inverse kinematics model of two mechanisms is verified.Secondly,the statics of 5RRP-RP redundantly actuated parallel mechanism is analyzed. The static equilibrium equation of the moving platform is established, and the static transfer matrix of the mechanism is obtained under the two modes of non-redundancy and redundancy. Driving force optimization scheme is established by using Lagrange multiplier method. The expression of driving force on each rod is solved. By using MATLAB software for example analysis,the driving force curves of parallel mechanisms are obtained under the condition of non-redundant and redundant actuation.Finally, the dynamic analysis of 5RRP-RP redundant actuation parallel mechanism is carried out. The generalized coordinates are selected and the kinetic expressions of each member are listed,the dynamic mathematical model of 5RRP-RP redundant actuation parallel mechanism is established by using Lagrange equation. The generalized force and driving force expressions are derived. The MATLAB software is used to solve the driving force curve of redundantly actuated parallel mechanism.