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6-DOF parallel manipulators with better dexterity, rotatability, or singularity-free workspace

Published online by Cambridge University Press:  01 July 2009

K. Y. Tsai*
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, 43 Keelung Road, Section 4, Taipei, Taiwan10672.
T. K. Lee
Affiliation:
Department of Mechanical Engineering, National Taiwan University of Science and Technology, 43 Keelung Road, Section 4, Taipei, Taiwan10672.
*
*Corresponding author. E-mail: [email protected]

Summary

Isotropic manipulators are generally considered as designs with optimum dexterity. Currently, many 6-DOF (degrees-of-freedom) isotropic parallel manipulators can be developed by numerical or analytical methods. At an isotropic configuration, a manipulator is equidistant from its neighboring singular points. The distance, however, can be very small, so an isotropic design might have relatively smaller singularity-free workspace. This paper presents methods to develop traditional 6-DOF parallel manipulators with better dexterity and larger singularity-free workspace. Some fully symmetric nontraditional designs are then proposed. The evaluation of kinematic properties shows that the fully symmetric designs have very good global dexterity, better rotatability, and relatively larger singularity-free workspace. The manipulators are suitable for some special tasks requiring higher precision, better rotatability, or larger workspace.

Type
Article
Copyright
Copyright © Cambridge University Press 2008

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References

1.Gosselin, C. M. and Angeles, J., “The optimum kinematic design of a planar three-degree-of freedom manipulator,” J. Mech. Trans. Automat. Design 110, 3541 (1988).CrossRefGoogle Scholar
2.Gosselin, C. M. and Angeles, J., “The optimum kinematic design of a spherical three-degree-of freedom manipulator,” J. Mech. Trans. Automat. Design 111, 202207 (1989).CrossRefGoogle Scholar
3.Gallant, M. and Boudreau, R., “The synthesis of planar parallel manipulators with prismatic joints for an optimum, singular-free workspace,” J. Rob. Syst. 19 (1), 1324 (2002).CrossRefGoogle Scholar
4.Hay, A. M. and Snyman, J. A., “Methodologies for the optimal design of parallel manipulators,” Int. J. Numer. Meth. Eng. 59 (3), 131152 (2004).CrossRefGoogle Scholar
5.Liu, X. J., Wang, J. and Pritschow, G., “A new family of 3-DoF fully-parallel manipulators with high rotational capability,” Mech. Mach. Theory 40, 475494 (2005).CrossRefGoogle Scholar
6.Pierrot, F., Reynaud, C. and Fournier, A., “DELTA: A simple and efficient parallel robot,” Robotica 8, 105109 (1990).CrossRefGoogle Scholar
7.Tsai, L. W. and Joshi, S., “Kinematics and optimization of a spatial 3-UPU parallel manipulator,” J. Mech. Design 122, 439446 (2000).CrossRefGoogle Scholar
8.Liu, X. J., Jeong, J. and Kim, J., “A three translational DoFs parallel cube-manipulator,” Robotica 21, 645653 (2003).CrossRefGoogle Scholar
9.Liu, X. J., Jin, Z. L. and Gao, F., “Optimum design of 3-DOF spherical parallel manipulators with respect to the conditioning and stiffness indices,” Mech. Mach. Theory 35, 12571267 (2000).CrossRefGoogle Scholar
10.Gregorio, R. Di, “A new family of spherical parallel manipulators,” Robotica 20, 353358 (2002).CrossRefGoogle Scholar
11.Pittens, K. H. and Podhorodeski, R. P., “A family of Stewart platforms with optimal dexterity,” J. Rob. Syst 10 (4), 463479 (1993).CrossRefGoogle Scholar
12.Stoughton, R. S. and Arai, T., “A modified Stewart platform manipulator with improved dexterity,” IEEE Trans. Rob. Automat. 9 (2), 166173 (1993).CrossRefGoogle Scholar
13.Zanganeh, K. E. and Angeles, J., “Kinematic isotropy and the optimum design of parallel manipulators,” Int. J. Rob. Res. 16 (2), 185196 (1997).CrossRefGoogle Scholar
14.Tsai, K. Y. and Huang, K. D., “The design of isotropic 6-DOF parallel manipulators using isotropy generators,” Mech. Mach. Theory 38 (11), 11991214 (2003).CrossRefGoogle Scholar
15.Tsai, K. Y. and Zhou, S. R., “The optimum design of 6-DOF isotropic parallel manipulators,” J. Rob. Syst. 22 (6), 333340 (2005).CrossRefGoogle Scholar
16.Angeles, J. and Lopez-Cajun, C. S., “Kinematic isotropy and the conditioning index of serial robotic manipulators,” Int. J. Rob. Res. 11 (6), 560571 (1992).CrossRefGoogle Scholar
17.Tsai, K. Y., Jang, Y. S. and Lee, T. K., “A new class of isotropic generators for developing 6-DOF isotropic manipulators,” To appear in Robotica, doi:10.1017/S0263574708004190, Published online by Cambridge University Press 10 March 2008.Google Scholar
18.Tsai, K. Y. and Wang, Z. W., “The design of redundant isotropic manipulators with special link parameters,” Robotica 23, 231237 (2005).CrossRefGoogle Scholar
19.Masory, O. and Wang, J., “Workspace evaluation of Stewart platform,” Adv. Rob. 9 (4), 443461 (1995).CrossRefGoogle Scholar
20.Bonev, I. A. and Ryu, J, “A new approach to orientation workspace analysis of 6-DOF parallel manipulators,” Mech. Mach. Theory 36 (1), 1528 (2001).CrossRefGoogle Scholar
21.Tsai, K. Y. and Lin, J. C., “Determining the compatible orientation workspace of Stewart-Gough parallel manipulators,” Mech. Mach. Theory 41 (10), 11681184 (2006).CrossRefGoogle Scholar
22.Tsai, K. Y.. Lee, T. K. and Huang, K. D., “Determining the workspace boundary of 6-DOF parallel manipulators,” Robotica 24, 605611 (2006).CrossRefGoogle Scholar