Design and Control Approaches for a Novel Planar Biped With Nearly Linear Dynamics

In this paper, we propose the design of a planar biped for which the model is nearly linear, i.e., the inertia matrix is a constant and the gravity terms in the equations of motion are still nonlinear, but simplified. The legs are designed such that the inertia matrix is independent of the joint variables. As a result, the nonlinear terms in the centrifugal and Coriolis terms disappear. In this design, each leg has two links that are connected by a revolute joint at the knee. The two legs are connected to each other at the hip. The center of mass (COM) of each leg is located at the hip using counterweights. We assume that the stance leg is locked at the knee during the support phase. For this system, the dynamic model for the swing phase is considered. The stability of these designs is analysed by considering these as linear systems with nonvanishing perturbations. The paper discusses issues of ultimate stability bounds of the system and tracking of desired trajectories.Copyright © 2005 by ASME

[1]  Jorge Angeles,et al.  Fundamentals of Robotic Mechanical Systems: Theory, Methods, and Algorithms , 1995 .

[2]  Arthur D Kuo,et al.  Energetics of actively powered locomotion using the simplest walking model. , 2002, Journal of biomechanical engineering.

[3]  Yildirim Hurmuzlu,et al.  Passively walking five-link robot , 2004, Autom..

[4]  H. Sebastian Seung,et al.  Actuating a simple 3D passive dynamic walker , 2004, IEEE International Conference on Robotics and Automation, 2004. Proceedings. ICRA '04. 2004.

[5]  Mark W. Spong,et al.  Further results on control of the compass gait biped , 2003, Proceedings 2003 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2003) (Cat. No.03CH37453).

[6]  Benoit Thuilot,et al.  Compass-Like Biped Robot Part I : Stability and Bifurcation of Passive Gaits , 1996 .

[7]  Russ Tedrake,et al.  Efficient Bipedal Robots Based on Passive-Dynamic Walkers , 2005, Science.

[8]  Zhiwei Luo,et al.  A novel gait generation for biped walking robots based on mechanical energy constraint , 2004, IEEE Trans. Robotics.

[9]  M. Coleman,et al.  The simplest walking model: stability, complexity, and scaling. , 1998, Journal of biomechanical engineering.

[10]  Franck Plestan,et al.  Stable walking of a 7-DOF biped robot , 2003, IEEE Trans. Robotics Autom..

[11]  Tad McGeer,et al.  Passive Dynamic Walking , 1990, Int. J. Robotics Res..

[12]  Bernard Espiau,et al.  Limit cycles and their stability in a passive bipedal gait , 1996, Proceedings of IEEE International Conference on Robotics and Automation.

[13]  Werner Schiehlen Energy-Optimal Design of Walking Machines , 2005 .