Optimal Design and Development of a Decoupled A/B-Axis Tool Head with Parallel Kinematics

This paper is an attempt to design a decoupled A/B-axis tool head with parallel kinematics, due to the increasing demand for A/B-axis tool heads in industry, particularly in thin wall machining applications for structural aluminium aerospace components. In order to carry out further analysis, the method of orientation description based on the azimuth and tilt angles is introduced, which is a convenient method describing kinematics, parasitic motions, and orientation workspace. For the purpose of optimal design, three indices are defined to evaluate the force transmission performance of the tool head. They have obvious physical significance and are dependent of any coordinate system. Based on the indices and their performance atlases, the optimization process is presented in detail. The parasitic motions and orientation capability of the designed tool head are analyzed finally. The results show that the designed device is far from singularity, has good force transmissibility, and has very high tilting angle. The indices and analysis and design method used here should be said to be extended to other parallel robots.

[1]  Xin-Jun Liu,et al.  On the optimal kinematic design of the PRRRP 2-DoF parallel mechanism , 2006 .

[2]  Bernard Roth,et al.  A Transmission Index for Spatial Mechanisms , 1973 .

[3]  Hiroaki Funabashi,et al.  Development of Spatial In-Parallel Actuated Manipulators with Six Degrees of Freedom with High Motion Transmissibility. , 1997 .

[4]  Clément Gosselin,et al.  A Global Performance Index for the Kinematic Optimization of Robotic Manipulators , 1991 .

[5]  G. H Sutherland,et al.  Dimensional synthesis of linkages by multifactor optimization , 1974 .

[6]  Ron P. Podhorodeski,et al.  A family of stewart platforms with optimal dexterity , 1993, J. Field Robotics.

[7]  Damien Chablat,et al.  Architecture optimization of a 3-DOF translational parallel mechanism for machining applications, the orthoglide , 2003, IEEE Trans. Robotics Autom..

[8]  Ilian A. Bonev,et al.  Orientation Capability, Error Analysis, and Dimensional Optimization of Two Articulated Tool Heads With Parallel Kinematics , 2008 .

[9]  Satish Chand,et al.  Transmission angle in mechanisms (Triangle in mech) , 2002 .

[10]  T. P. Goodman,et al.  Kinematics and Linkage Design , 1986 .

[11]  J. T. Kimbrell,et al.  Kinematics Analysis and Synthesis , 1991 .

[12]  Philip A. Voglewede,et al.  Measuring "closeness" to singularities for parallel manipulators , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[13]  Damien Chablat,et al.  Workspace Analysis of the Orthoglide using Interval Analysis , 2007, ArXiv.

[14]  Ferdinand Freudenstein,et al.  Kinematic Synthesis of Linkages , 1965 .

[15]  C. Gosselin,et al.  The optimum kinematic design of a spherical three-degree-of-freedom parallel manipulator , 1988 .

[16]  J. Merlet.  Jacobian, Manipulability, Condition Number and Accuracy of Parallel Robots , 2005, ISRR.

[17]  Marco Ceccarelli,et al.  Optimal design of CaPaMan (Cassino Parallel Manipulator) with a specified orientation workspace , 2002, Robotica.

[18]  Xin-Jun Liu,et al.  A new methodology for optimal kinematic design of parallel mechanisms , 2007 .

[19]  Zexiang Li,et al.  Optimal design of parallel manipulators for maximum effective regular workspace , 2005, 2005 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[20]  Xin-Jun Liu.  Optimal kinematic design of a three translational DoFs parallel manipulator , 2006, Robotica.

[21]  D. C. Tao,et al.  Applied linkage synthesis , 1964 .

[22]  Kurt Hain.  Applied kinematics / Kurt Hain , 1967 .

[23]  Jinsong Wang,et al.  Kinematics, singularity and workspace of planar 5R symmetrical parallel mechanisms , 2006 .

[24]  Delbert Tesar,et al.  Link Length Bounds on the Four-Bar Chain , 1971 .

[25]  Tatsuo Arai,et al.  A modified Stewart platform manipulator with improved dexterity , 1993, IEEE Trans. Robotics Autom..