Design and Analysis of a New Non-Parasitic Parallel Mechanism for 2T1R Motion

Abstract

Two-limb parallel mechanisms (PMs) can have several advantages, such as avoidance of mechanical collision, fairly simple architecture, easy assembly, and large workspace. The paper presents a novel two-limb three-degree-of-freedom (DOF) PM with two translations and one-rotation (2T1R) that are actuated by two sliders. The manipulator runs with decoupled position and orientation with forward position solution without parasitic motions. The main topological characteristics of the PM such as position and orientation characteristic (POC), DOF, and coupling degree are analyzed. Second, using the kinematic modeling method based on topological characteristics, the unified symbolic forward and inverse position solutions of the two configurations of the PM (I and II) are derived together with the workspace, rotational capacity, and singularity. Finally, a comparative analysis regarding the kinematics of two configurations (I and II) is carried out to find an optimal design configuration I of a PM for 2T1R motion.