Simulation and computer-aided design of spherical parallel manipulators

The determination of workspace is an essential step in the development of parallel manipulators. By extending the virtual-chain (VC) approach to the type synthesis of parallel manipulators, this technical brief proposes a VC approach to the workspace analysis of parallel manipulators. This method is first outlined before being illustrated by the production of a three-dimensional (3D) computer-aided-design (CAD) model of a 3-RPS parallel manipulator and evaluating it for the workspace of the manipulator. Here, R, P and S denote revolute, prismatic and spherical joints respectively. The VC represents the motion capability of moving platform of a manipulator and is shown to be very useful in the production of a graphical representation of the workspace. Using this approach, the link interferences and certain transmission indices can be easily taken into consideration in determining the workspace of a parallel manipulator.

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Solving reachable workspace of some parallel manipulators by computer-aided design variation geometry

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/09544062jmes1069 ◽

2008 ◽

Vol 222 (9) ◽

pp. 1773-1781 ◽

Cited By ~ 20

Author(s):

Y Lu ◽

Y Shi ◽

B Hu

Keyword(s):

Computer Aided Design ◽

Degrees Of Freedom ◽

Parallel Manipulators ◽

Six Degrees Of Freedom ◽

Reachable Workspace ◽

Spline Curves ◽

Computer Aided ◽

Design Variation ◽

Aided Design ◽

The Given

To shape the workspace of some novel parallel manipulators (PMs) is significant. A novel computer-aided design (CAD) variation geometry approach is proposed to shape and solve the reachable workspace of some PMs with three to six degrees of freedom (DOFs). Some basic techniques are described for designing the simulation mechanism and solving the reachable workspace. The simulation mechanisms of some PMs with three to six DOFs are created. When varying the driving dimensions of the active legs in the given extent, the simulation mechanisms vary correspondingly, and the position components of the moving platform are solved automatically. By transferring the position solutions into spatial spline curves in the simulation mechanism, all the boundary surfaces of the workspace can be created and visualized dynamically. Comparing with analytic approaches for solving workspace, the CAD variation geometry approach is simple, straightforward, accurate, and repeatable.

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Performance atlases of the workspace for planar 3-DOF parallel manipulators

Robotica ◽

10.1017/s0263574700002678 ◽

2000 ◽

Vol 18 (5) ◽

pp. 563-568 ◽

Cited By ~ 34

Author(s):

Xin-Jun Liu ◽

Jinsong Wang ◽

Feng Gao

Keyword(s):

Physical Model ◽

Optimum Design ◽

Computer Aided Design ◽

Solution Space ◽

Parallel Manipulators ◽

Performance Characteristics ◽

Performance Criteria ◽

Computer Aided ◽

Aided Design

The design of the robotic mechanisms is most important because they determine the performance characteristics of the robots. This paper concerns the issue of computer-aided design (CAD) for planar 3-DOF parallel robotic mechanisms by means of the physical model of the solution space, which can be used systematically to express the relationships between the performance criteria and all link lengths of one type of the robtic mechanism. The performance atlases of the workspace volume for the manipulators are plotted in the physical model of the solution space. The characteristics of the distribution of the workspace shapes in the physical model of the solution space are presented. The results are useful for the optimum design of the robotic mechanisms. This paper proposes a new way for robotic CAD.

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WORKSPACE ANALYSIS AND OPTIMIZATION OF THE PARALLEL ROBOTS BASED ON COMPUTER-AIDED DESIGN APPROACH

Facta Universitatis Series Mechanical Engineering ◽

10.22190/fume190428006a ◽

2020 ◽

Vol 18 (1) ◽

pp. 079

Author(s):

Badreddine Aboulissane ◽

Larbi El Bakkali ◽

Jalal El Bahaoui

Keyword(s):

Computer Aided Design ◽

Three Dimensional ◽

Kinematic Chain ◽

Parallel Manipulators ◽

Parallel Robots ◽

Design Parameters ◽

Reachable Workspace ◽

Design Variables ◽

Computer Aided ◽

Aided Design

This paper provides workspace determination and analysis based on the graphical technique of both spatial and planar parallel manipulators. The computation and analysis of workspaces will be carried out using the parameterization and three-dimensional representation of the workspace. This technique is implemented in CAD (Computer Aided Design) Software CATIA workbenches. In order to determine the workspace of the proposed manipulators, the reachable region by each kinematic chain is created as a volume/area; afterwards, the full reachable workspace is obtained by the application of a Boolean intersection function on the previously generated volumes/areas. Finally, the relations between the total workspace and the design parameters are simulated, and the Product Engineering Optimizer workbench is used to optimize the design variables in order to obtain a maximized workspace volume. Simulated annealing (SA) and Conjugate Gradient (CG) are considered in this study as optimization tools.

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Solving elastic deformation of some parallel manipulators with linear active legs using computer-aided design variation geometry

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406213478374 ◽

2013 ◽

Vol 227 (12) ◽

pp. 2810-2824 ◽

Cited By ~ 1

Author(s):

Yi Lu ◽

Cong Cong ◽

Chen Liwei ◽

Peng Wang

Keyword(s):

Elastic Deformation ◽

Computer Aided Design ◽

Parallel Manipulator ◽

Parallel Manipulators ◽

Elastic Deformations ◽

Deformation Equation ◽

Computer Aided ◽

Force Transformation ◽

Design Variation ◽

Aided Design

It has been a significant and challenging issue to determine the elastic deformation of parallel manipulators for their precision analysis and control. A new method is proposed and studied for solving the elastic deformation of some parallel manipulators with linear active legs using computer-aided design variation geometry. First, an original simulation mechanism of a parallel manipulator is constructed; each of the vectors in the force transformation matrix of the parallel manipulators is constructed by this simulation mechanism. The active/constrained wrench and their pose are determined based on the Newton–Euler formulation. Second, the elastic deformed dimensions of the active legs are determined based on the elastic deformation equation and the active/constrained wrench. Third, a new simulation mechanism of this parallel manipulator is constructed by replacing the original dimensions of active legs with the deformed dimensions of active legs and the elastic deformations of parallel manipulators are solved using the pose difference between the original and new simulation mechanisms. Finally, two parallel manipulators are illustrated and their elastic deformations are solved and verified by both analytic approach and finite element method.

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