Kinematic modeling and optimization of a new reconfigurable parallel mechanism

Abstract

This paper investigates a new reconfigurable parallel mechanism consisting of three SvPS kinematic limbs. Induced by phase changes of a metamorphic spherical variable-axis joint (Sv), the SvPS limb is capable of changing to two typical configurations, of which one exerts no constraint and the other exerts a constraint force to the moving platform. Reconfiguration of the three limbs enables the 3-SvPS parallel mechanism to have four distinct configurations with degrees of freedom (DOF) varying from 3 to 6. Analytical model of position and workspace analysis of the reconfigurable parallel mechanism are first investigated. In terms of the screw theory, a unified Jacobian matrix covering all the mobility configurations is established and utilized for analyzing singularity of the parallel mechanism in different configurations. Further, performance analysis and optimization are explored using the motion/force transmission method. The 3-SvPS parallel mechanism can be used as structure of reconfigurable robotic machine center with adaptability to changing task requirements.

Constraint and Mobility Change Analysis of Rubik’s Cube-inspired Reconfigurable Joints and Corresponding Parallel Mechanisms

“…The motion screws are reciprocal to S r and the basis of screw system can be calculated from Eq. (19), that is Hence, the 3(rA-4)P(rA-3) parallel mechanism has pure rational DOF.…”

“…A new type of reconfigurable modular parallel robot was proposed by Carbonari et al [16], which is equipped with a locking system to fix one of the revolute joints and is able to perform different types of motion, especially pure translation and pure rotation. Ye et al [17][18][19] proposed a family of reconfigurable parallel mechanism with reconfigurable hybrid limbs based on diamond kinematic chain. The reconfigurable parallel mechanism has ability to perform variable motion modes, such as 3T, 2T1R, 2R1T and 3R.…”

On the Study of Configuration and Kinematics of a 3-DOF Generalized Spherical Parallel Mechanism for Ankle Rehabilitation

“…In addition, all the actuators of the parallel mechanism are prismatic pairs, and the direction of the real unit of the $ Ti is consistent with the direction of the ith actuator. According to the reciprocity product theory, $ T1  $ 13 , $ T2  $ 23 and $ T3  $ 41 are always equal to 1. So, the parallel mechanism has no inverse singularity.…”

Neural Network and Performance Analysis for a Novel Reconfigurable Parallel Manipulator Based on the Spatial Multiloop Overconstrained Mechanism

“…In this case, the reconfigurable parallel mechanisms have been the hot area in the parallel mechanism field. In order to obtain a novel reconfigurable parallel mechanism, researchers presented many ways, like modularity [5][6][7], metamorphic link or joint [8][9][10], and reconfigurable link [11,12] or mechanism [2]. The initial reconfigurable parallel mechanisms are proposed using the modularization, which can change their configuration by adding or locking some modular components.…”