Novel leg adjustment approach for hopping and running

The ability to perform efficient and robust locomotion is crucial condition for real-world legged robots. Unlike running and walking [1], stable hopping cannot be achieved with a fixed angle of attack with respect to ground. Also, the region of attraction for stable running is quite small with fixed angle of attack. This drawback and sensitivity to running velocity and control parameters exist in common leg adjustment methods. In this study, the superiority of the new method regarding aforementioned concerns is shown for running and hopping SLIP model. Its similarity to human hopping strategy to cope with perturbation was shown in [2]. The presented method, called VBLA (Velocity Based Leg Adjustment) can achieve dead beat response for perturbed hopping. With this approach, running in a large range of velocities can be obtained.

[1]  Reinhard Blickhan,et al.  Compliant leg behaviour explains basic dynamics of walking and running , 2006, Proceedings of the Royal Society B: Biological Sciences.

[2]  Andre Seyfarth,et al.  Human leg adjustment in perturbed hopping , 2013 .

[3]  Majid Nili Ahmadabadi,et al.  Controllers for robust hopping with upright trunk based on the Virtual Pendulum concept , 2012, 2012 IEEE/RSJ International Conference on Intelligent Robots and Systems.

[4]  André Seyfarth,et al.  Leg-adjustment strategies for stable running in three dimensions , 2012, Bioinspiration & biomimetics.

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