Reconfiguration of a 3-(rR)PS Metamorphic Parallel Mechanism Based on Complete Workspace and Operation Mode Analysis

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Latifah Nurahmi ◽  
Dongming Gan
Keyword(s):  
Parallel Mechanism ◽  
Operation Mode ◽  
Mode Analysis ◽  
Finite Point ◽  
Constraint Equations ◽  
Revolute Joints ◽  
Operation Modes ◽  
Identification Approach ◽  
Moving Platform ◽  
Mode A

Abstract This paper focuses on the reconfiguration of a 3-(rR)PS metamorphic parallel mechanism based on complete workspace and operation mode analysis. The mechanism consists of three (rR)PS legs, and each (rR) joint is composed of two perpendicular revolute joints. One of the (rR) joint axes can be reconfigured continuously, which allows the mechanism to exhibit three distinct configurations. Initially, the constraint equations are derived by using algebraic geometry approach, and the primary decomposition is computed for the three configurations. It reveals that the 3-(rR)PS metamorphic parallel mechanism can exhibit one up to two operation modes among three configurations. When the second axes of the three (rR) joints intersect at a finite point and not coplanar, the 3-(rR)PS metamorphic parallel mechanism has only one operation mode. If the second axes of the three (rR) joints are coplanar, the 3-(rR)PS metamorphic parallel mechanism has two operation modes. It is shown that both operation modes have the same motion type, namely, 1T2R motion. However, to realize the same trajectories in both operation modes, the moving platform will have different orientations. Hence, the orientation workspaces of both operation modes are characterized and the axodes are used to compare the instantaneous motion of the moving platform when passing through the same trajectories. Based on these results, an identification approach is introduced to identify which operation mode a given mechanism pose belongs to and this provides a useful method for trajectory planning.

scholarly journals Reconfiguration Analysis of a 3-DOF Parallel Mechanism

Robotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 66
Author(s):  
Maurizio Ruggiu ◽  
Xianwen Kong
Keyword(s):  
Parallel Mechanism ◽  
Degrees Of Freedom ◽  
Operation Mode ◽  
Parallel Mechanisms ◽  
Universal Joint ◽  
Kinematic Chains ◽  
Constraint Equations ◽  
The Third ◽  
Equilateral Triangles ◽  
Moving Platform

This paper deals with the reconfiguration analysis of a 3-DOF (degrees-of-freedom) parallel manipulator (PM) which belongs to the cylindrical parallel mechanisms family. The PM is composed of a base and a moving platform shaped as equilateral triangles connected by three serial kinematic chains (legs). Two legs are composed of two universal (U) joints connected by a prismatic (P) joint. The third leg is composed of a revolute (R) joint connected to the base, a prismatic joint and universal joint in sequence. A set of constraint equations of the 1-RPU−2-UPU PM is derived and solved in terms of the Euler parameter quaternion (a.k.a. Euler-Rodrigues quaternion) representing the orientation of the moving platform and of the Cartesian coordinates of the reference point on the moving platform. It is found that the PM may undergo either the 3-DOF PPR or the 3-DOF planar operation mode only when the base and the moving platform are identical. The transition configuration between the operation modes is also identified.

Dynamic Analysis of the 3-RRPS Metamorphic Parallel Mechanism Based on Instantaneous Screw Axis

2019 ◽  
Author(s):  
Latifah Nurahmi ◽  
Dongming Gan
Keyword(s):  
Dynamic Analysis ◽  
Parallel Mechanism ◽  
Operation Mode ◽  
Translational Motion ◽  
Time Derivative ◽  
Screw Axis ◽  
Operation Modes ◽  
Instantaneous Screw Axis ◽  
Moving Platform ◽  
Instantaneous Screw

Abstract The 3-rRPS metamorphic parallel mechanism can change its configurations thanks to the reconfigurable (rR) joint. The analysis in this paper will focus on one specific configuration where the moving-platform is able to perform 2-dof coupled rotational motions and 1-dof translational motion, which is well-known as 1T2R motion. In this configuration, the mechanism has two types of operation modes, i.e. x0 = 0 and x3 = 0, which have been extensively studied by many researchers. However, the dynamic behaviours of the mechanism in those two operation modes have not been studied. Accordingly, this paper presents the dynamic analysis of the 3-rRPS metamorphic parallel mechanism in both operation modes based on the Instantaneous Screw Axis (ISA). The types of operation mode are initially characterized by means of Euler-Quaternion parameters. The time derivative of transformation matrix is performed in each operation mode and the ISA can be determined. By using the ISA, velocities and accelerations of all points on the moving-platform can be evaluated, which become the foundation of the dynamic analysis in this paper. This approach can be applied to parallel mechanisms having multiple operation modes of different mobility.

Type Synthesis of Variable Degrees-of-Freedom Parallel Manipulators With Both Planar and 3T1R Operation Modes

2012 ◽  
Author(s):  
Xianwen Kong
Keyword(s):  
Degrees Of Freedom ◽  
Operation Mode ◽  
Parallel Manipulators ◽  
Type Synthesis ◽  
Operation Modes ◽  
Moving Platform ◽  
Multiple Operation ◽  
Schönflies Motion

Parallel manipulators (PMs) with multiple operation modes are novel reconfigurable PMs which use less number of actuators and can be reconfigured without disassembly. Although several classes of PMs with multiple operation modes that have the same DOF (degrees-of-freedom) in all the operation modes have been proposed, only one class of variable-DOF PMs with multiple operation modes — PMs with multiple operation modes that do not have the same DOF in all the operation modes — have been proposed so far. This paper deals with the type synthesis of variable-DOF PMs with both planar and 3T1R (or Schönflies motion which has three translational DOF and 1 rotational DOF) operation modes. The axes of rotation of the moving platform in the planar operation mode are not parallel to the axes of rotation of the moving platform in the 3T1R operation mode. At first, an approach to the type synthesis of PMs with multiple operation modes is recalled. Based on the results on the type synthesis of planar PMs and 3T1R PMs, the types of variable-DOF PMs with both planar and 3T1R operation modes are then obtained. This work can be extended to the type synthesis of other classes of PMs with multiple operation modes.

Forward displacement analysis of a new 1CCC–5SPS parallel mechanism using Gröbner theory

2009 ◽  
Vol 223 (5) ◽  
pp. 1233-1241 ◽  
Author(s):  
D Gan ◽  
Q Liao ◽  
J S Dai ◽  
S Wei ◽  
L D Seneviratne
Keyword(s):  
Parallel Mechanism ◽  
Polynomial Equation ◽  
Polynomial Equations ◽  
Geometrical Constraint ◽  
Degree Polynomial ◽  
Forward Displacement ◽  
Constraint Equations ◽  
Moving Platform ◽  
Forward Kinematic ◽  
Forward Displacement Analysis

A new parallel mechanism 1CCC–5SPS which has distance and angle constraints is introduced in this article. Degree of freedom and forward kinematic analysis of this new parallel mechanism are presented, in which four equivalent polynomial equations are obtained from the original six geometrical constraint equations. The Gröbner basis theory is used with the four equations and the problem of forward displacement is reduced to a 40th degree polynomial equation in a single unknown from a constructed 10 × 10 Sylvester's matrix which is small in size, from which 40 different locations of the moving platform can be derived. A numerical example confirms the efficiency of the procedure.

Dynamic Modeling and Analysis of a 3 PRS Parallel Mechanism Using Constrained Robotic Approach

2010 ◽  
Author(s):  
Meng-Shiun Tsai ◽  
Wei-Hsiung Yuan
Keyword(s):  
Parallel Mechanism ◽  
Driving Forces ◽  
Robotic Approach ◽  
Constraint Forces ◽  
Modeling And Analysis ◽  
Constraint Equations ◽  
Reaction Forces ◽  
Internal Forces ◽  
Moving Platform ◽  
Novel Model

In this paper, a novel model is developed to analyze a 3-PRS parallel mechanism. The 3-PRS mechanism consists of a moving platform which is manipulated by three actuated fingers. Since the fingertips are constrained by the moving platform, three holonomic constraint equations are derived and the associated constraint forces are studied based on the theory of differential geometry. The developed model could be utilized to separate the dynamics of the fingers and that of the moving platform such that the coupling behaviors of the fingers can be investigated. It is found that the reaction forces applied at the fingertips of the parallel manipulator include not only the driving forces to the moving platform but also the constraint forces. Besides, the constraint forces are determined to be internal forces which would not generate a net force or torque to drive the moving platform. Simulations are performed to study the dynamic behavior of the reaction forces and it is found that the constraint forces have significant effect on the actuated fingers.

Geometric Constraint-based Reconfiguration and Self-motions of a 4-CRU Parallel Mechanism

2021 ◽  
pp. 1-21
Author(s):  
Latifah Nurahmi ◽  
Pradiktio Putrayudanto ◽  
Guowu Wei ◽  
Sunil K. Agrawal
Keyword(s):  
Parallel Mechanism ◽  
New Technology ◽  
Operation Mode ◽  
Geometric Constraints ◽  
Geometric Constraint ◽  
Primary Decomposition ◽  
Sustainable Housing ◽  
Additional Mode ◽  
Moving Platform ◽  
Self Motion

Abstract This paper aims to investigate the reconfiguration and self-motions of a 4-CRU parallel mechanism based on the mechanism geometric constraints. The targeted application of such mechanism in this research is for 3D-printing buildings of multi-directional nozzle as a new technology for constructing sustainable housing. By using primary decomposition, four geometric constraints are identified and the reconfiguration analysis is carried out in each of these. It reveals that each geometric constraint will have three distinct operation modes, namely Schoenflies mode, reversed Schoenflies mode and an additional mode. The additional mode can be either 4-DOF mode or it degenerates into 3-DOF mode, depending on the type of the geometric constraint. By taking into account the actuation and constraint singularities, the workspace of each operation mode is analysed and geometrically illustrated. It allows us to determine the regions in which the reconfiguration takes place. Furthermore, the moving-platform can still perform at least 1-DOF self-motion. It occurs at two specific actuated leg lengths. Demonstration of reconfiguration process and self-motions are also provided through a mock-up prototype.

scholarly journals Classification of a 3-RER Parallel Manipulator Based on the Type and Number of Operation Modes

2020 ◽  
pp. 1-17
Author(s):  
Xianwen Kong
Keyword(s):  
Parallel Manipulator ◽  
Operation Mode ◽  
Mode Analysis ◽  
Type Number ◽  
Systematic Classification ◽  
Operation Modes ◽  
Solid Foundation ◽  
And Control ◽  
The Impact

Abstract The type/number of operation modes of a parallel manipulator (PM) may vary with the link parameters of the PM. This paper presents a systematic classification of a 3-RER PM based on the type/number of operation modes. The 3-RER PM was proposed as a 4-DOF (degree-of-freedom) 3T1R PM in the literature. Using the proposed method, the classification of a PM based on the type/number of operation modes can be carried out in four steps, including formulation of constraint equations of the PM, preliminary classification of the PM using Gröbner Cover, operation mode analysis of all the types of PMs using primary decomposition of ideals, and identification redundant types of PMs. Classification of the 3-RER PM shows that it has 19 types. Besides the two 4-DOF 3T1R operation modes, different types of 3-RER PMs may have up to two more 3-DOF or other types of 4- DOF operation modes. This work is the first systematic study on the impact of link parameters on the operation modes of the 3-RER PM and provide a solid foundation for further research on the design and control of 3-RER PMs and other multi-mode (or reconfigurable) PMs.

scholarly journals Form and Operation Mode Analysis of a Novel Solar-Driven Cogeneration System with Various Collector Types

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Haofei Zhang ◽  
Bo Lei ◽  
Tao Yu ◽  
Zhida Zhao
Keyword(s):  
Operation Mode ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Mode Analysis ◽  
Solar Collectors ◽  
Operating Modes ◽  
Operation Modes ◽  
Cogeneration System ◽  
Heating Load ◽  
Evacuated Tube Collectors

In this study, the form and operation modes of a novel solar-driven cogeneration system consisted of various solar collectors (flat plat collectors (FPC), evacuated tube collectors (ETC), and parabolic trough collectors (PTC)) and ORC (organic Rankine cycle) based on building heating load are analyzed. This paper mainly obtains the fitting formula of thermal efficiency of the ORC power generation device and determines the form and operation mode of the cogeneration system. The form is the same, but the operation modes are different for PTC and FPC or ETC. There are six operating modes, respectively, based on the size relationship between the heating load of buildings and the effective heat collection of the solar collector subsystem when the solar collectors are PTC or FPC and ETC.

Type Synthesis of 3-DOF Parallel Manipulators With Both Planar and Translational Operation Modes

2011 ◽  
Author(s):  
Xianwen Kong
Keyword(s):  
Operation Mode ◽  
Parallel Manipulators ◽  
Planar Motion ◽  
Type Synthesis ◽  
Recent Advances ◽  
Operation Modes ◽  
Open Issue ◽  
Moving Platform ◽  
Multiple Operation ◽  
Planar Parallel Manipulators

Despite recent advances in the type synthesis of parallel manipulators with a mono-operation mode, such as translational parallel manipulators and spherical parallel manipulators, the type synthesis of parallel manipulators with multiple operation modes is still an open issue. This paper deals with the type synthesis of 3-DOF parallel manipulators with both planar and translational operation modes. The type synthesis of planar parallel manipulators, which refer to parallel manipulators in which the moving platform undergoes planar motion, is first dealt with using the virtual chain approach. Then, the types of 3-DOF parallel manipulators with both planar and translational operation modes are obtained. This work can be extended to the type synthesis of other classes of parallel manipulators with multiple operation modes.

Type Synthesis of 3-DOF Parallel Manipulators With Both a Planar Operation Mode and a Spatial Translational Operation Mode1

2013 ◽  
Vol 5 (4) ◽  
Author(s):  
Xianwen Kong
Keyword(s):  
Operation Mode ◽  
Parallel Manipulators ◽  
Planar Motion ◽  
Type Synthesis ◽  
Revolute Joints ◽  
Reconfigurable Mechanisms ◽  
Open Issue ◽  
Moving Platform ◽  
Multiple Operation ◽  
Planar Parallel Manipulators

Type synthesis of multimode parallel manipulators (PMs) (also parallel manipulators with multiple operation modes) is an open issue in the research on reconfigurable mechanisms and robots. This paper deals with the type synthesis of 3-DOF (degree-of-freedom) parallel manipulators with both a planar operation mode and a spatial translational operation mode. The type synthesis of planar parallel manipulators, which refer to parallel manipulators in which the moving platform undergoes planar motion, is first dealt with using the virtual-chain approach. Types of planar parallel manipulators, including those involving Bennett compositional unit (CU), are obtained. Then, the types of 3-DOF parallel manipulators with both a planar operation mode and a translational operation mode are obtained. This paper focuses on 3-DOF parallel manipulators composed of only revolute joints. This work contributes to the type synthesis of parallel manipulators and can be extended to the type synthesis of other classes of multimode parallel manipulators.

Sign in / Sign up

Export Citation Format

Share Document