Workspace Analysis of a Three DOF Cable-Driven Mechanism

A cable-driven mechanism based on the idea of BetaBot (2005, "A New Cable-Based Parallel Robot With Three Degrees of Freedom, " Multibody Syst. Dyn., 13, pp. 371-383) is analyzed and geometrical description of its workspace boundary is found. In this mechanism, the cable arrangement eliminates the rotational motions leaving the moving platform with three translational motions. The mechanism has potentials for large scale manipulation and robotics in harsh environments. A detailed analysis of the tensionable workspace of the mechanism is presented. The mechanism, in a tensionable position, can develop tensile forces in all cables to maintain its rigidity under arbitrary external loading. A set of conditions on the geometry of the mechanism is proposed for which the tensionable workspace becomes a well defined convex polyhedron. The geometrical shape of the workspace is then described and the tensionability of the mechanism inside the workspace is proved. The proof is quite general and based on a geometrical approach.

[1]  A. Ming,et al.  Study on multiple degree-of-freedom positioning mechanism using wires. I: Concept, design and control , 1994 .

[2]  Roger V. Bostelman,et al.  Applications of the NIST ROBOCRANE. , 1994 .

[3]  Manfred Hiller,et al.  Workspace, Stiffness, Singularities and Classification of Tendon-Driven Stewart Platforms , 1998 .

[4]  Mustafa Shabbir Kurbanhusen,et al.  Force-closure workspace analysis of cable-driven parallel mechanisms , 2006 .

[5]  Sadao Kawamura,et al.  High-speed manipulation by using parallel wire-driven robots , 2000, Robotica.

[6]  L. W. Tsai,et al.  Robot Analysis: The Mechanics of Serial and Parallel Ma-nipulators , 1999 .

[7]  Imme Ebert-Uphoff,et al.  Wrench-feasible workspace generation for cable-driven robots , 2006, IEEE Transactions on Robotics.

[8]  Leila Notash,et al.  CAT4 (Cable Actuated Truss - 4 Degrees of Freedom): A Novel 4 DOF Cable Actuated Parallel Manipulator , 2002, J. Field Robotics.

[9]  Clément Gosselin,et al.  On the Properties and the Determination of the Wrench-Closure Workspace of Planar Parallel Cable-Driven Mechanisms , 2004 .

[10]  Robert L. Williams,et al.  Cable-suspended robotic contour crafting system , 2007 .

[11]  Vijay R. Kumar,et al.  Workspaces of Cable-Actuated Parallel Manipulators , 2006 .

[12]  Jie Liu,et al.  A New Wire-Driven Three Degree-of-Freedom Parallel Manipulator , 2006 .

[13]  Imme Ebert-Uphoff,et al.  Wrench-based analysis of cable-driven robots , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[14]  Philip A. Voglewede,et al.  On the connections between cable-driven robots, parallel manipulators and grasping , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[15]  Imme Ebert-Uphoff,et al.  Force-feasible workspace analysis for underconstrained, point-mass cable robots , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[16]  Yuxin Su,et al.  Development of a large parallel-cable manipulator for the feed-supporting system of a next-generation large radio telescope , 2001, J. Field Robotics.

[17]  R. Clavel.  Conception d'un robot parallèle rapide à 4 degrés de liberté , 1991 .

[18]  Clément Gosselin,et al.  Analysis of the wrench-closure workspace of planar parallel cable-driven mechanisms , 2006, IEEE Transactions on Robotics.

[19]  James S. Albus,et al.  The NIST robocrane , 1993, J. Field Robotics.

[20]  Manfred Hiller,et al.  Estimating the Controllable Workspace of Tendon-Based Stewart Platforms , 2000 .

[21]  Saeed Behzadipour,et al.  A New Cable-Based Parallel Robot with Three Degrees of Freedom , 2005 .