A 2T-2R, 4-DOF Parallel Manipulator

From the first ideas of parallel manipulator proposed by Gough and Stewart, parallel manipulators have been found in many industrial applications. In the past two decades, a number of interesting mechanical devices and design methods have been extensively studied. However, most efforts are dedicated to six degrees of freedom (6-DOF) or 3-DOF manipulators. There is a need for equipment providing more than 3 DOFs arranged in parallel and based on simpler arrangements than 6-DOF arrangements in application. This paper presents a novel 4-DOF parallel platform manipulator with base mounted prismatic actuators. The movable platform of the manipulator can translate along two directions and rotate around two axes respectively (2T-2R). The kinematics model is formulated, which describes the inverse and forward kinematics transformation. The singularity analysis of this new 2T-2R, 4-DOF parallel manipulator is introduced.