Biomechanics Research Today is a free monthly online journal that collates and summarizes the latest research about Biomechanics, including details on mechanics of living organisms, movement, locomotion, prosthetic limbs.

Dynamics and stability of lateral plane locomotion on inclines.

Schmitt J, Bonnono S

School of Mechanical, Industrial and Manufacturing Engineering, Oregon State University, Rogers 204, Corvallis, OR 97331, USA. schmitjo@engr.orst.edu

An actuated, lateral leg spring model is developed to investigate lateral plane locomotion dynamics and stability on inclines. A single actuation input, the force-free leg length, is varied in a feedforward fashion to explicitly and implicitly match prescribed lateral and fore-aft force profiles, respectively. Forward dynamic simulations incorporating the prescribed leg actuation are employed to identify periodic orbits for gaits in which the leg acts to either push the body away from or pull the body towards the foot placement point. Gait stability and robustness to external perturbation are found to vary significantly as a function of slope and velocity for each type of leg function. Results of these analyses suggest that the switch in leg function from pushing to pulling is governed by gait robustness, and occurs at increasing inclines for increasing velocities.

Published 6 November 2009 in J Theor Biol, 261(4): 598-609.
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