Passive quadrupedal bounding with a segmented flexible torso

This paper examines the effect of torso flexibility on the dynamics of quadrupedal running with a bounding gait. A reduced-order passive and conservative model with a segmented flexible torso and compliant legs is introduced to study torso-leg coordination. Numerical return map studies reveal that a large variety of cyclic bounding motions can be realized passively, as a natural mode of the system. Despite the simplicity of the model, the resulting motions correspond to torso bending movements that resemble those in galloping mammals without explicit reliance on the fine structural and morphological details. This way, the proposed model offers a unifying description of the task-level locomotion behavior, and can be used to inform feedback control synthesis by serving as a behavioral target for the control system.

[1]  M. Hildebrand.  Motions of the Running Cheetah and Horse , 1959 .

[2]  N. Schilling,et al.  Sagittal spine movements of small therian mammals during asymmetrical gaits , 2006, Journal of Experimental Biology.

[3]  Qinghua Liang,et al.  Quasi passive bounding of a quadruped model with articulated spine , 2012 .

[4]  Kenneth J. Waldron,et al.  The Mechanics of Quadrupedal Galloping and the Future of Legged Vehicles , 1999, Int. J. Robotics Res..

[5]  Fumiya Iida,et al.  New Robotics: Design Principles for Intelligent Systems , 2005, Artificial Life.

[6]  Luther R. Palmer,et al.  System Design of a Quadrupedal Galloping Machine , 2004, Int. J. Robotics Res..

[7]  Martin Buehler,et al.  Modeling and Experiments of Untethered Quadrupedal Running with a Bounding Gait: The Scout II Robot , 2005, Int. J. Robotics Res..

[8]  R. F. Ker,et al.  Elastic structures in the back and their rôle in galloping in some mammals , 2009 .

[9]  P. J. Holmes,et al.  Nonlinear Oscillations, Dynamical Systems, and Bifurcations of Vector Fields , 1983, Applied Mathematical Sciences.

[10]  Hugh M. Herr,et al.  A Galloping Horse Model , 2001, Int. J. Robotics Res..

[11]  Evangelos Papadopoulos,et al.  Self-stabilising quadrupedal running by mechanical design , 2009 .

[12]  George A. Bekey,et al.  Gait Adaptation in a Quadruped Robot , 2002, Auton. Robots.

[13]  Fumiya Iida,et al.  "Cheap" Rapid Locomotion of a Quadruped Robot: Self-Stabilization of Bounding Gait , 2004 .

[14]  Philip Holmes,et al.  Stability Analysis of Legged Locomotion Models by Symmetry-Factored Return Maps , 2004, Int. J. Robotics Res..

[15]  Martin S. Fischer,et al.  Mechanical self-stabilization, a working hypothesis for the study of the evolution of body proportions in terrestrial mammals? , 2006 .

[16]  David E. Orin,et al.  Intelligent control of quadruped gallops , 2003 .

[17]  Yasuhiro Fukuoka,et al.  Stable quadrupedal running based spring-loaded two-segment legged on a model , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[18]  Kevin Blankespoor,et al.  BigDog, the Rough-Terrain Quadruped Robot , 2008 .

[19]  Utku Culha,et al.  Quadrupedal bounding with an actuated spinal joint , 2011, 2011 IEEE International Conference on Robotics and Automation.

[20]  Marc H. Raibert,et al.  Legged Robots That Balance , 1986, IEEE Expert.

[21]  P. Holmes,et al.  Nonlinear Oscillations, Dynamical Systems, and Bifurcations of Vector Fields , 1983, Applied Mathematical Sciences.