Method for Force Analysis of the Overconstrained Parallel Mechanism Considering the Link’s Spatial Composite Elastic Deformations

This paper provides an approach to model the reaction force of origami mechanisms when they are deformed. In this approach, an origami structure is taken as an equivalent redundantly actuated mechanism, making it possible to apply the forward-force analysis to calculating the reaction force of the origami structure. Theoretical background is provided in the framework of screw theory, where the repelling screw is introduced to integrate the resistive torques of folded creases into the reaction-force of the whole origami mechanism. Two representative origami structures are then selected to implement the developed modeling approach, as the widely used waterbomb base and the waterbomb-based integrated parallel mechanism. With the proposed kinematic equivalent, their reaction forces are obtained and validated, presenting a ground for force analysis of origami-inspired mechanisms.

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Dynamics Analysis of 3-PPR Planar Parallel Mechanism Including Friction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1006-1007.265 ◽

2014 ◽

Vol 1006-1007 ◽

pp. 265-270

Author(s):

Ying Mei ◽

Xiao Xue Gao ◽

Jie Song

Keyword(s):

Mechanical Model ◽

Parallel Mechanism ◽

Dynamics Analysis ◽

Kinematic Pair ◽

Force Analysis

In order to obtain actual dynamics equation of 3-PPR planar parallel mechanism, established mechanical model of kinematic pair including friction, carried on force analysis of 3-PPR planar parallel mechanism including friction. Then according to the Kane equation established the dynamics equation of 3-PPR planar parallel mechanism including friction.

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Stiffness Analysis and Design of a Compact Modified Delta Parallel Mechanism

Robotica ◽

10.1017/s0263574704000050 ◽

2004 ◽

Vol 22 (4) ◽

pp. 463-475 ◽

Cited By ~ 36

Author(s):

Woo-Keun Yoon ◽

Takashi Suehiro ◽

Yuichi Tsumaki ◽

Masaru Uchiyama

Keyword(s):

Parallel Mechanism ◽

Rotation Axis ◽

Haptic Interface ◽

Structural Stiffness ◽

Parallel Mechanisms ◽

Simple Method ◽

Elastic Deformations ◽

Stiffness Analysis ◽

Analysis And Design ◽

Parallel Link

In our previous work, we developed a compact 6-DOF haptic interface as a master device which achieved an effective manual teleoperation. The haptic interface contains a modified Delta parallel-link positioning mechanism. Parallel mechanisms are usually characterized by a high stiffness, which, however, is reduced by elastic deformations of both parts and bearings. Therefore, to design such a parallel mechanism, we should analyze its structural stiffness, including elastic deformations of both parts and bearings. Then we propose a simple method to analyze structural stiffness in a parallel mechanism using bearings. Our method is based on standard concepts such as static elastic deformations. However, the important aspect of our method is the manner in which we combine these concepts and how we obtain the value of the elasticity coefficient of a rotation axis in a bearing. Finally, we design a modified Delta mechanism, with a well-balanced stiffness, based on our method of stiffness analysis.

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Stiffness Design, Analysis and Validation of a Parallel-Mechanism Equivalent Suspension System

Volume 5B: 39th Mechanisms and Robotics Conference ◽

10.1115/detc2015-46641 ◽

2015 ◽

Author(s):

Chen Qiu ◽

Ketao Zhang ◽

Jing Shan Zhao ◽

Jian S. Dai

Keyword(s):

Parallel Mechanism ◽

Optimization Design ◽

Screw Theory ◽

Suspension System ◽

Force Analysis ◽

Design Constraint ◽

Kinematic Design ◽

Simulation Validation ◽

Element Simulation ◽

Stiffness Design

This paper provides a systematic approach to design a vehicle’s independent suspension system. In this approach, multi-link type suspension is selected. By treating it as a parallel mechanism, both the kinematic design and force analysis are conducted in the same framework of screw theory. Regarding the kinematic design, constraint-based approach is used to find suitable layouts of constraint limbs in accordance with desired degree of freedom. In the force analysis, stiffness matrix of the suspension mechanism is developed, leading to the deformation and stress analysis under various critical loads. The developed formulae are further utilized to design suitable suspension mechanism, followed by finite-element-simulation validation as well as optimization design to reduce the resulted maximum stresses.

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A method for force analysis of the overconstrained lower mobility parallel mechanism

Mechanism and Machine Theory ◽

10.1016/j.mechmachtheory.2015.01.004 ◽

2015 ◽

Vol 88 ◽

pp. 31-48 ◽

Cited By ~ 27

Author(s):

Yundou Xu ◽

Wenlan Liu ◽

Jiantao Yao ◽

Yongsheng Zhao

Keyword(s):

Parallel Mechanism ◽

Force Analysis ◽

Lower Mobility

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A force analysis of a 3-RPS parallel mechanism by using screw theory

Robotica ◽

10.1017/s0263574711000129 ◽

2011 ◽

Vol 29 (7) ◽

pp. 959-965 ◽

Cited By ~ 11

Author(s):

Y. Zhao ◽

J. F. Liu ◽

Z. Huang

Keyword(s):

Parallel Mechanism ◽

Screw Theory ◽

Mechanical Design ◽

Parallel Manipulators ◽

Simultaneous Equations ◽

Force Analysis ◽

New Approach ◽

Numerical Example ◽

And Control

SUMMARYThe force analysis of parallel manipulators is one of the important issues for mechanical design and control, but it is quite difficult often because of the excessive unknowns. A new approach using screw theory for a 3-RPS parallel mechanism is proposed in this paper. It is able to markedly reduce the number of unknowns and even make the number of simultaneous equations to solve not more than six each time, which may be called force decoupling. With this method, first the main-pair reactions need to be solved for, and then, the active forces and constraint reactions of all other kinematic pairs can be simultaneously obtained by analyzing the equilibrium of each body one by one. Finally, a numerical example and a discussion are given.

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A method for analyzing parallel mechanism stiffness including elastic deformations in the structure

IEEE/RSJ International Conference on Intelligent Robots and System ◽

10.1109/irds.2002.1041707 ◽

2003 ◽

Cited By ~ 6

Author(s):

Woo-Keun Yoon ◽

T. Suehiro ◽

Y. Tsumaki ◽

M. Uchiyama

Keyword(s):

Parallel Mechanism ◽

Elastic Deformations

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Kinematic, Workspace and Force Analysis of a five-DOF Hybrid Manipulator R(2RPR)R/SP+RR

10.21203/rs.3.rs-624423/v1 ◽

2021 ◽

Author(s):

Yundou Xu ◽

Fan Yang ◽

Youen Mei ◽

Dongsheng Zhang ◽

Yulin Zhou ◽

...

Keyword(s):

Parallel Mechanism ◽

Structure Optimization ◽

Force Analysis ◽

Body Model ◽

Hybrid Manipulator ◽

Simulation Based ◽

Processing Ability ◽

Cutting Experiment ◽

Position Solution ◽

Is Design

Abstract In the present study, the over-constrained hybrid manipulator R(2RPR)R/SP + RR is considered as the research objective. In this paper, kinematics of the hybrid manipulator, including the forward and inverse position, are analyzed. Then, the workspace is checked based on the inverse position solution to evaluate whether the workspace of the hybrid manipulator meets the requirements, and the actual workspace of the hybrid robot is analyzed. After that, the force analysis of the over-constrained parallel mechanism is carried out, and an ADAMS-ANSYS rigid-flexible hybrid body model is established to verify the simulation. Based on the obtained results from the force analysis, the manipulator structure is design. Then, the structure optimization is carried out to improve the robot stiffness. Finally, calibration and workspace verification experiments are performed on the prototype, cutting experiment of an S-shaped aluminum alloy workpiece is completed, and the experiment verifies the processing ability of the prototype and proves that the prototype has good application prospects.

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Principle of Force Analysis of Overconstrained Parallel Mechanisms Considering Link Weight

Robotica ◽

10.1017/s0263574719000109 ◽

2019 ◽

Vol 37 (9) ◽

pp. 1533-1544

Author(s):

Yundou Xu ◽

Ling Lu ◽

Wenlan Liu ◽

Jinwei Guo ◽

Jiantao Yao ◽

...

Keyword(s):

The Other ◽

Parallel Mechanisms ◽

Additional Component ◽

Force Analysis ◽

Elastic Deformations ◽

Link Weight ◽

Limb Stiffness ◽

Fundamental Cause ◽

Deformation Compatibility ◽

Component Force

SummaryThe fundamental cause for the statically indeterminate problem in the force analysis of overconstrained parallel mechanisms (PMs) is found to be the presence of the linearly dependent overconstrained wrenches. Based on the fundamental cause, a unified expression of the solution for the magnitudes of the constraint wrenches of both the limb stiffness decoupled and limb stiffness coupled overconstrained PMs is derived. When the weight of each link is considered, depending on whether additional component forces are generated along the axes of the overconstrained wrenches, two different situations should be considered. One situation is that no additional component force is generated along the axes of the overconstrained wrenches under the weight of the links in the corresponding limb. In this case, the added constraint wrenches at the limb’s end can be calculated directly, and used as a part of the generalized external wrench. The other situation is that additional component forces are generated. In this case, the elastic deformations in the axes of the overconstrained wrenches generated by those component forces should be considered, and the deformation compatibility equations between the overconstrained wrenches are reformulated.

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