Kinematic Analysis and Application Research on a High-Speed Travelling Double Four-Rod Spatial Parallel Mechanism

2002 ◽  
Vol 19 (12) ◽  
pp. 873-878 ◽  
Author(s):  
K. Zhou ◽  
D. Mao ◽  
Z. Tao
2010 ◽  
Vol 4 (4) ◽  
pp. 364-371 ◽  
Author(s):  
Nobuyuki Iwatsuki ◽  
◽  
Norifumi Nishizaka ◽  
Koichi Morikawa ◽  
Koji Kondoh ◽  
...  

This paper describes the kinematic analysis and motion control of a hyper redundant robot built by serially connecting many units with a few DOF. Each unit of the manipulator is a spatial parallel mechanism with 3 DOF and is composed of 2 stages connected with 3 linear actuators, 7 spherical joints, and a center rod. The forward kinematic analysis of the manipulator based on the forward kinematics of each unit by numerical calculation was carried out. The inverse kinematic analysis, the iterative calculation so as to converge output error while output displacement is distributed into each unit with weighting coefficient, was proposed and formulated. Motion control of the robot was theoretically and experimentally examined based on the inverse kinematics. It was confirmed that a prototype with 3 units could generate the desired trajectories.


2019 ◽  
Vol 16 (5) ◽  
pp. 172988141987591 ◽  
Author(s):  
Xiulong Chen ◽  
Chenghao Sun

The parallel mechanism has advantages of the high speed, high precision, strong carrying capacity, and high structural rigidity. Most of the previous studies concerning the dynamic modeling focused on planar mechanisms with revolute clearance joints or spatial mechanisms with one spherical joint clearance, while few studies focused on spatial parallel mechanisms with multi-spherical joint clearances. In this article, a general dynamic modeling method for spatial parallel mechanism with multi-spherical joint clearances based on Lagrange multiplier method is proposed. Taking 4universal joint-prismatic joint-spherical joint/universal joint-prismatic joint- universal joint (4UPS-UPU) spatial parallel mechanism as an example, the constraint equations of common kinematic pairs in spatial parallel mechanism, such as universal joint, spherical joint, and prismatic joint, are derived in detail. The dynamic model of the parallel mechanism with two spherical joint clearances combining the Flores contact force model and the LuGre friction model is established. The correctness of model has also been verified by comparing the analysis results of MATLAB with those of ADAMS. It can be seen that dynamic model of spatial parallel mechanism with multi-spherical joint clearances could be easily established by this method, which provides a theoretical reference to establish the dynamic model of other parallel mechanism with multi-clearance in the future.


2021 ◽  
pp. 1-23
Author(s):  
Ganmin Zhu ◽  
Shimin Wei ◽  
Ying Zhang ◽  
Qizheng Liao

Abstract This paper demonstrates a novel geometric modeling and computational method of the family of spatial parallel mechanisms with 3-R(P)S structure for direct kinematic analysis based on the point pair relationship. The point pair relationship, which is derived from the framework of conformal geometric algebra (CGA), consists of the relationship between the point and the point pair and two point pairs. The first research is on the distance relationship between the point and the point pair. Secondly, the derivation of the distance relationship between two point pairs is based on the aforementioned result, which shows the mathematical homogeneity. Thirdly, two formulations for a point of the point pairs that satisfy the distance relationship between two point pairs are reduced. Fourthly, the point pair relationship is applied to solve the direct kinematic analysis of the spatial parallel mechanism with 3-R(P)S structure. Finally, four numerical examples are provided to verify the validity of the proposed algorithm. Overall, the proposed method can be generalized for the direct kinematics of a series of spatial parallel mechanisms with 3-R(P)S structure.


2013 ◽  
Vol 20 (10) ◽  
pp. 2676-2684 ◽  
Author(s):  
Xiu-long Chen ◽  
Wen-bin Li ◽  
Yu Deng ◽  
Yun-feng Li

Author(s):  
DU Hui ◽  
GAO Feng ◽  
PAN Yang

A novel 3-UP3R parallel mechanism with six degree of freedoms is proposed in this paper. One most important advantage of this mechanism is that the three translational and three rotational motions are partially decoupled: the end-effector position is only determined by three inputs, while the rotational angles are relative to all six inputs. The design methodology via GF set theory is brought out, using which the limb type can be determined. The mobility of the end-effector is analyzed. After that, the kinematic and velocity models are formulated. Then, workspace is studied, and since the robot is partially decoupled, the reachable workspace is also the dexterous workspace. In the end, both local and global performances are discussed using conditioning indexes. The experiment of real prototype shows that this mechanism works well and may be applied in many fields.


2013 ◽  
Vol 816-817 ◽  
pp. 821-824
Author(s):  
Xue Mei Niu ◽  
Guo Qin Gao ◽  
Zhi Da Bao

Kinematic analysis plays an important role in the research of parallel kinematic mechanism. This paper addresses a novel forward kinematic solution based on RBF neural network for a novel 2PRRR-PPRR redundantly actuated parallel mechanism. Simulation results illustrate the validity and feasibility of the kinematic analysis method.


2021 ◽  
Vol 18 (3) ◽  
pp. 172988142110177
Author(s):  
Jia Yonghao ◽  
Chen Xiulong

For spatial multibody systems, the dynamic equations of multibody systems with compound clearance joints have a high level of nonlinearity. The coupling between different types of clearance joints may lead to abundant dynamic behavior. At present, the dynamic response analysis of the spatial parallel mechanism considering the three-dimensional (3D) compound clearance joint has not been reported. This work proposes a modeling method to investigate the influence of the 3D compound clearance joint on the dynamics characteristics of the spatial parallel mechanism. For this purpose, 3D kinematic models of spherical clearance joint and revolute joint with radial and axial clearances are derived. Contact force is described as normal contact and tangential friction and later introduced into the nonlinear dynamics model, which is established by the Lagrange multiplier technique and Jacobian of constraint matrix. The influences of compound clearance joint and initial misalignment of bearing axes on the system are analyzed. Furthermore, validation of dynamics model is evaluated by ADAMS and Newton–Euler method. This work provides an essential theoretical basis for studying the influences of 3D clearance joints on dynamic responses and nonlinear behavior of parallel mechanisms.


Sign in / Sign up

Export Citation Format

Share Document