The problem of biped locomotion at steady speeds is discussed through a
Lagrangian formulation developed for velocity-dependent, body driving forces.
Human walking on a level surface is analyzed in terms of the data on the
resultant ground-reaction force and the external work. It is shown that the
trajectory of the center of mass is due to a superposition of its rectilinear
motion with a given speed and a backward rotation along a shortened
hypocycloid. A stiff-to-compliant crossover between walking gaits is described
and the maximum speed for human walking, given by an instability of the
trajectory, is predicted.
Key words: locomotion, integrative biology, muscles, bipedalism, human
walking, biomechanics.Comment: 9 pages, 4 figure