A novel reconfigurable parallel mechanism constructed with spatial metamorphic four-link mechanism

Abstract

In this paper, a spatial metamorphic four-link mechanism (SMM) based on the metamorphic universal joint is proposed. By adjusting the axis position of the universal joint, three kinds of SMMs are constructed. Each kind of SMM has different bifurcation and metamorphic characteristics. Starting from the motion characteristics of each phase of SMM based on the screw theory, a reconfigurable hybrid limb is constructed by combining it with the series branch which can provide a constraint force and a constraint couple. The constraint changes of metamorphic hybrid limbs corresponding to different phases of SMM are analyzed. This leads to the design of a new type of reconfigurable parallel mechanism (RPM), in which the platform is connected to the base by three reconfigurable hybrid limbs. The results show that the performance of the RPM can be changed from 6 degrees of freedom (DOFs) to 5, 4, and 3 DOFs.

CGA-based approach for direct kinematics of a novel reconfigurable parallel mechanism

“…Ye et al [4] extracted the common parts of C-limbs and F-limbs and named them FClimbs. Combining an FC-limb with a kinematotropic linkage, a hybrid kinematics chain with variable constraints was obtained and then used to synthesize a class of reconfigurable PMs, and similar approaches are also found in the works of Jia et al [5]. They are expected to be applied in the field of additive-subtractive hybrid manufacturing, but their direct kinematics problems(DKPs) have not been thoroughly solved yet.…”

Reconfiguration Analysis and Characteristics of a Novel 8-Link Variable-DOF Planar Mechanism with Five Motion Modes

“…Considerable progress has been made in the type synthesis and reconfiguration analysis of variable-DOF mechanisms, including singleloop spatial mechanisms [5,7,12], parallel mechanisms [11,[13][14][15][16][17][18][19][20], multi-mode mobile parallel mechanisms [21], and multi-loop mechanisms [4,5,[22][23][24][25][26][27][28][29]. It should be noted that variable-DOF mechanisms are composed of conventional kinematic joints and do not involve variable kinematic joints [30], reconfigurable kinematic joints [31] or metamorphic kinematic joints [32].…”