Kinematics analysis of a novel 2R1T 3-PUU parallel mechanism with multiple rotation centers

摘要

In this paper, we present a novel three-degree-of-freedom (3-DOF) 3-PUU parallel mechanism (PM) with multiple rotation centers. Having two rotational DOFs and one translational DOF, the 3-PUU parallel robot consists of a fixed platform, a movable platform, and three identical PUU branches. Each PUU branch is composed of one prismatic(P) joint and two universal(U) joints. The mobility of initial configuration of the 3-PUU PM is analyzed using the reciprocal screw theory. Analysis of the 3-PUU PM's mobility of general configuration is performed based on its geometrical characteristics. The movable platform of the 3-PUU PM is demonstrated to be capable of rotating around multiple points. The singularities of 3-PUU PM are discussed. Using the inverse kinematics method, the workspace is obtained. Numerical examples are provided to illustrate the motion characteristics of the 3-PUU PM as a mechanism with multiple rotation centers. (C) 2020 Elsevier Ltd. All rights reserved.