Mechanics of Continuum Robots with External Loading and General Tendon Routing

Routing tendons in straight paths along an elastic backbone is a widely used method of actuation for continuum robots. Tendon routing paths which are general curves in space enable a much larger family of robots to be designed, with configuration spaces and workspaces that are unattainable with straight tendon routing. Harnessing general tendon routing to extend the capabilities of continuum robots requires a model for the kinematics and statics of the robot, which is the primary focus of this paper. Our approach is to couple the classical Cosserat theories of strings and rods using a geometrically exact derivation of the distributed loads that the tendons impose along the robot. Experiments demonstrate that the model accurately predicts tip position to 1.7% of the total arc length, on a prototype robot that includes both straight and helical tendon routing and is subject to both point and distributed loads.

[1]  Ricardo Baeza-Yates,et al.  Computer Science 2 , 1994 .

[2]  John Kenneth Salisbury,et al.  Mechanics Modeling of Tendon-Driven Continuum Manipulators , 2008, IEEE Transactions on Robotics.

[3]  S. Antman Nonlinear problems of elasticity , 1994 .

[4]  Christopher D. Rahn,et al.  Geometrically Exact Models for Soft Robotic Manipulators , 2008, IEEE Transactions on Robotics.

[5]  Gregory S. Chirikjian,et al.  Kinematically optimal hyper-redundant manipulator configurations , 1992, Proceedings 1992 IEEE International Conference on Robotics and Automation.

[6]  D. Caleb Rucker,et al.  A Geometrically Exact Model for Externally Loaded Concentric-Tube Continuum Robots , 2010, IEEE Transactions on Robotics.

[7]  J. H. Davis,et al.  A model for the embedded tendon control of a slender three-dimensional flexible robot link , 1994 .

[8]  Ian D. Walker,et al.  Large deflection dynamics and control for planar continuum robots , 2001 .

[9]  Richard M. Murray,et al.  A Mathematical Introduction to Robotic Manipulation , 1994 .

[10]  Kai Xu,et al.  Analytic Formulation for Kinematics, Statics, and Shape Restoration of Multibackbone Continuum Robots Via Elliptic Integrals , 2010 .

[11]  Ian D. Walker,et al.  Soft robotics: Biological inspiration, state of the art, and future research , 2008 .

[12]  Pierre E. Dupont,et al.  Quasistatic modeling of concentric tube robots with external loads , 2010, 2010 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[13]  J. Bruce C. Davies,et al.  Continuum robots - a state of the art , 1999, Proceedings 1999 IEEE International Conference on Robotics and Automation (Cat. No.99CH36288C).

[14]  Robert J. Webster,et al.  Design and Kinematic Modeling of Constant Curvature Continuum Robots: A Review , 2010, Int. J. Robotics Res..

[15]  Gregory S. Chirikjian,et al.  Hyper-redundant manipulator dynamics: a continuum approximation , 1994, Adv. Robotics.

[16]  J. F. Wilson,et al.  The mechanics and positioning of highly flexible manipulator limbs , 1989 .

[17]  Ian A. Gravagne,et al.  Manipulability, force, and compliance analysis for planar continuum manipulators , 2002, IEEE Trans. Robotics Autom..

[18]  Christopher D. Rahn,et al.  Design of Continuous Backbone, Cable-Driven Robots , 2002 .

[19]  Bryan A. Jones,et al.  Three dimensional statics for continuum robotics , 2009, 2009 IEEE/RSJ International Conference on Intelligent Robots and Systems.