The frequency of human, manual adjustments in balancing an inverted pendulum is constrained by intrinsic physiological factors.
Ian D Loram, Peter J Gawthrop, Martin Lakie
The Journal of Physiology | Published : 2006
While standing naturally and when manually or pedally balancing an equivalent inverted pendulum, the load sways slowly (characteristic unidirectional duration approximately 1 s) and the controller, calf muscles or hand, makes more frequent adjustments (characteristic unidirectional duration 400 ms). Here we test the hypothesis that these durations reflect load properties rather than some intrinsic property of the human neuromuscular system. Using a specialized set-up mechanically analogous to real standing, subjects manually balanced inverted pendulums with different moments of inertia through a compliant spring representing the Achilles tendon. The spring bias was controlled by a sensitive ..View full abstract