Most multimode parallel robots can change operation modes by passing through constraint singularities. This paper deals with a comprehensive kinematic study of a three degrees-of-freedom (DOF) multimode three-PRPiR parallel robot developed at Heriot-watt University. This robot is able to reach several operation modes without crossing any constraint singularity by using lockable Pi and R joints. Here, a Pi joint may act as a 1DOF planar parallelogram if its lockable P (prismatic) joint is locked or a 2DOF RR serial chain if its lockable P joint is released. The operation modes of the robot include a 3T operation mode and four 2T1R operation modes with two different directions of the rotation axis of the moving platform. The inverse kinematics and forward kinematics of the robot in each operation mode are dealt with in detail. The joint space and workspace analysis of the robot allow us to know the regions of the workspace that the robot can reach in each operation mode. It is shown that the robot is able to change assembly mode in one operation mode by passing through another operation mode.

References

1.
Fanghella
,
P.
,
Galletti
,
C.
, and
Gianotti
,
E.
,
2006
, “
Parallel Robots That Change Their Group of Motion
,”
Advances in Robot Kinematics
,
Springer
,
Dordrecht The Netherlands
, pp.
49
56
.
2.
Refaat
,
S.
,
Hervé
,
J. M.
,
Nahavandi
,
S.
, and
Trinh
,
H.
,
2007
, “
Two-Mode Overconstrained Three-DOFs Rotational-Translational Linear-Motor-Based Parallel Kinematics Mechanism for Machine Tool Applications
,”
Robotica
,
25
(
4
), pp.
461
466
.
3.
Kong
,
X.
,
Gosselin
,
C.
, and
Richard
,
P. L.
,
2007
, “
Type Synthesis of Parallel Mechanisms With Multiple Operation Modes
,”
ASME J. Mech. Des.
,
129
(
6
), pp.
595
601
.
4.
Li
,
Q.
, and
Hervé
,
J. M.
,
2009
, “
Parallel Mechanisms With Bifurcation of Schoenflies Motion
,”
IEEE Trans. Rob.
,
25
(
1
), pp.
pp. 158
164
.
5.
Gogu
,
G.
,
2011
, “
Maximally Regular T2R1-Type Parallel Manipulators With Bifurcated Spatial Motion
,”
ASME J. Mech. Rob.
,
3
(
1
), p.
011010
.
6.
Ruggiu
,
M.
, and
Kong
,
X.
,
2012
, “
Mobility and Kinematic Analysis of a Parallel Mechanism With Both PPR and Planar Operation Modes
,”
Mech. Mach. Theory
,
55
, pp.
77
90
.
7.
Kong
,
X.
,
2012
, “Type Synthesis of Variable Degrees-of-Freedom Parallel Manipulators With Both Planar and 3T1R Operation Modes,”
ASME
Paper No. DETC2012-70621.
8.
Kong
,
X.
,
2013
, “
Type Synthesis of 3-DOF Parallel Manipulators With Both a Planar Operation Mode and a Spatial Translational Operation Mode
,”
ASME J. Mech. Rob.
,
5
(
4
), p.
041015
.
9.
Kong
,
X.
, and
Yu
,
J.
,
2015
, “
Type Synthesis of Two-Degrees-of-Freedom 3-4R Parallel Mechanisms With Both Spherical Translation Mode and Sphere-on-Sphere Rolling Mode
,”
ASME J. Mech. Rob.
,
7
(
4
), p.
041018
.
10.
Gan
,
D.
, and
Dai
,
J. S.
,
2013
, “
Geometry Constraint and Branch Motion Evolution of 3-PUP Parallel Mechanisms With Bifurcated Motion
,”
Mech. Mach. Theory
,
61
, pp.
168
183
.
11.
Zeng
,
Q.
, and
Ehmann
,
K. F.
,
2014
, “
Design of Parallel Hybrid-Loop Manipulators With Kinematotropic Property and Deployability
,”
Mech. Mach. Theory
,
71
, pp.
1
26
.
12.
Ye
,
W.
,
Fang
,
Y.
,
Zhang
,
K.
, and
Guo
,
S.
,
2014
, “
A New Family of Reconfigurable Parallel Mechanisms With Diamond Kinematotropic Chain
,”
Mech. Mach. Theory
,
74
, pp.
1
9
.
13.
Ding
,
X.
,
Kong
,
X.
, and
Dai
,
J. S.
,
2016
,
Advances in Reconfigurable Mechanisms and Robots II
,
Springer International Publishing
, London.
14.
Coste
,
M.
, and
Demdah
,
K. M.
,
2015
, “
Extra Modes of Operation and Self Motions in Manipulators Designed for Schoenflies Motion
,”
ASME J. Mech. Rob.
,
7
(
4
), p.
041020
.
15.
Nurahmi
,
L.
,
Caro
,
S.
,
Wenger
,
P.
,
Schadlbauer
,
J.
, and
Husty
,
M.
,
2016
, “
Reconfiguration Analysis of a 4-RUU Parallel Manipulator
,”
Mech. Mach. Theory
,
96
(
Pt. 2
), pp.
269
289
.
16.
Gan
,
D.
,
Dai
,
J. S.
, and
Liao
,
Q.
,
2009
, “
Mobility Change in Two Types of Metamorphic Parallel Mechanisms
,”
ASME J. Mech. Rob.
,
1
(
4
), p.
041007
.
17.
Zhang
,
K. T.
,
Dai
,
J. S.
, and
Fang
,
Y. F.
,
2012
, “
Geometric Constraint and Mobility Variation of Two 3-SPS Metamorphic Parallel Mechanisms
,”
ASME J. Mech. Rob.
,
135
(
1
), p.
011001
.
18.
Kong
,
X.
, and
Jin
,
Y.
,
2016
, “
Type Synthesis of 3-DOF Multi-Mode Translational/Spherical Parallel Mechanisms With Lockable Joints
,”
Mech. Mach. Theory
,
96
(Pt. 2), pp.
323
333
.
19.
Carbonari
,
L.
,
Callegari
,
M.
,
Palmieri
,
G.
, and
Palpacelli
,
M.-C.
,
2014
, “
A New Class of Reconfigurable Parallel Kinematic Machines
,”
Mech. Mach. Theory
,
79
, pp.
173
183
.
20.
Walter
,
D. R.
,
Husty
,
M. L.
, and
Pfurner
,
M.
,
2009
, “
Chapter A: Complete Kinematic Analysis of the SNU 3-UPU Parallel Manipulator
,”
Contemporary Mathematics
, Vol.
496
,
American Mathematical Society
,
Providence, RI
, pp.
331
346
.
21.
Kong
,
X.
,
2014
, “
Reconfiguration Analysis of a 3-DOF Parallel Mechanism Using Euler Parameter Quaternions and Algebraic Geometry Method
,”
Mech. Mach. Theory
,
74
, pp.
188
201
.
22.
Kong
,
X.
,
2016
, “
Reconfiguration Analysis of a 4-DOF 3-RER Parallel Manipulator With Equilateral Triangular Base and Moving Platform
,”
Mech. Mach. Theory
,
98
, pp.
180
189
.
23.
Kong
,
X.
,
2016
, “Reconfiguration Analysis of a Variable Degrees-of-Freedom Parallel Manipulator With Both 3-DOF Planar and 4-DOF 3T1R Operation Modes,”
ASME
Paper No. DETC2016-59203.
24.
Chablat
,
D.
,
Jha
,
R.
,
Rouillier
,
F.
, and
Moroz
,
G.
,
2014
, “
Non-Singular Assembly Mode Changing Trajectories in the Workspace for the 3-RPS Parallel Robot
,”
Advances in Robot Kinematics
, Springer International Publishing, Cham, Switzerland, pp.
149
159
.
25.
Chablat
,
D.
,
Jha
,
R.
,
Rouillier
,
F.
, and
Moroz
,
G.
,
2014
, “Workspace and Joint Space Analysis of the 3-RPS Parallel Robot,”
ASME
Paper No. DETC2014-34593.
26.
Zhang
,
C.
,
2015
, “Improvement of a Disassembly-Free Reconfigurable Parallel Manipulator,”
M.Sc. dissertation
, Heriot-Watt University, Edinburgh, UK.
27.
Nenchez
,
D. N.
, and
Uchiyama
,
M.
,
1995
, “
Singularity-Consistent Path Tracking: A Null Space Based Approach
,”
IEEE
International Conference on Robotics and Automation
, Nagoya, Japan, May 21–27, pp.
2482
2489
.
28.
Innocenti
,
C.
, and
Parenti-Castelli
,
V.
,
1998
, “
Singularity-Free Evolution From One Configuration to Another in Serial and Fully-Parallel Manipulators
,”
ASME J. Mech. Des.
,
120
(
1
), pp.
73
79
.
29.
Zein
,
M.
,
Wenger
,
P.
, and
Chablat
,
D.
,
2008
, “
Non-Singular Assembly-Mode Changing Motions for 3-RPR Parallel Manipulators
,”
Mech. Mach. Theory
,
43
(
4
), pp.
480
490
.
30.
Chablat
,
D.
, and
Wenger
,
P.
,
1998
, “
Working Modes and Aspects in Fully-Parallel Manipulator
,”
IEEE
International Conference on Robotics and Automation
, Leuven, Belgium, May 16–20, pp.
1964
1969
.
31.
Company
,
O.
, and
Pierrot
,
F.
,
2002
, “
Modelling and Design Issues of a 3-Axis Parallel Machine-Tool
,”
Mech. Mach. Theory
,
37
(
11
), pp.
1325
1345
.
32.
Chablat
,
D.
, and
Wenger
,
P.
,
2003
, “
Architecture Optimization of a 3-DOF Parallel Mechanism for Machining Applications, the Orthoglide
,”
IEEE Trans. Rob. Autom.
,
19
(
3
), pp.
403
410
.
33.
Chablat
,
D.
,
Wenger
,
P.
,
Majou
,
F.
, and
Merlet
,
J. P.
,
2004
, “
An Interval Analysis Based Study for the Design and the Comparison of 3-DOF Parallel Kinematic Machines
,”
Int. J. Rob. Res.
,
23
(
6
), pp.
615
624
.
34.
Kong
,
X.
, and
Gosselin
,
C. M.
,
2005
, “
Type Synthesis of 3-DOF PPR-Equivalent Parallel Manipulators Based on Screw Theory and the Concept of Virtual Chain
,”
ASME J. Mech. Des.
,
127
(
6
), pp.
1113
1121
.
35.
Chablat
,
D.
,
Kong
,
X.
, and
Zhang
,
C.
,
2017
, “Kinematics, Workspace and Singularity Analysis of a Multi-Mode Parallel Robot,”
ASME
Paper No. DETC2017-67284.
36.
Pashkevich
,
A.
,
Chablat
,
D.
, and
Wenger
,
P.
,
2006
, “
Kinematics and Workspace Analysis of a Three-Axis Parallel Manipulator: The Orthoglide
,”
Robotica
,
24
(
1
), pp.
39
49
.
37.
Gosselin
,
C.
, and
Angeles
,
J.
,
1990
, “
Singularity Analysis of Closed-Loop Kinematic Chains
,”
IEEE Trans. Rob. Autom.
,
6
(
3
), pp.
281
290
.
38.
Wenger
,
P.
, and
Chablat
,
D.
,
1997
, “
Definition Sets for the Direct Kinematics of Parallel Manipulators
,”
Eighth International Conference in Advanced Robotics
(
ICAR
), Monterey, CA, July 7–9, pp.
859
864
.
39.
Siropa
, 2010, “A Library for Manipulator Singularities Analysis,” INRIA/CNRS, Paris, France, accessed, Jan. 30, 2018, http://siropa.gforge.inria.fr/doc/files/Siropa/modeling-mpl.html
40.
Pashkevich
,
A.
,
Wenger
,
P.
, and
Chablat
,
D.
,
2005
, “
Design Strategies for the Geometric Synthesis of Orthoglide-Type Mechanisms
,”
Mech. Mach. Theory
,
40
(
8
), pp.
907
930
.
41.
Collins
,
G. E.
,
1975
,
Quantifier Elimination for Real Closed Fields by Cylindrical Algebraic Decomposition
,
Springer, Berlin
.
42.
Manubens
,
M.
,
Moroz
,
G.
,
Chablat
,
D.
,
Wenger
,
P.
, and
Rouiller
,
F.
,
2012
, “
Cusp Points in the Parameter Space of Degenerate 3-RPR Planar Parallel Manipulators
,”
ASME J. Mech. Rob.
,
4
(
4
), p. 041003.
43.
Lazard
,
D.
, and
Rouillier
,
F.
,
2007
, “
Solving Parametric Polynomial Systems
,”
J. Symbolic Comput.
,
42
(
6
), pp.
636
667
.
You do not currently have access to this content.