Jixie chuandong (Dec 2020)
Kinematics and Workspace Analysis of 3-UU/UPU+2P Hybrid Mechanism
Abstract
A new 3-UU/UPU+2P double-layer hybrid mechanism is proposed in view of the characteristics of the hybrid mechanism having both the advantages of the serial and parallel mechanisms. Firstly,the structural characteristics of the mechanism are described in detail,and a dynamic and static coordinate system is constructed. Secondly,the degree of freedom of the mechanism is analyzed based on the spiral theory,and the degree of freedom is verified by using the modified G-K formula. It is concluded that the mechanism has 3 degrees of freedom and belongs to a non-transient mechanism. Then,based on the kinematic characteristics of the mechanism,the forward and inverse solution models of the kinematics of the mechanism are established,and the differential solution method of symbolic operation is used to analyze the forward and velocity solutions of the mechanism. The change curves of kinematics model are obtained through specific numerical examples,and the theoretical calculation results are compared with Adams simulation results to verify the correctness of the kinematics model. Finally,the workspace of the mechanism is analyzed based on Monte Carlo method,which provides theoretical basis for the configuration design and practical application of the mechanism. The research results show that the mechanism has a large continuous and symmetrical workspace.