Functions of Proprioceptive Inputs in Normal and Perturbed Walking

摘要

The goal of our project is to incorporate principles of design and regulation ofwalking by biological sense organs into sensors for legged robots. Both animals and robots must utilize information from sensors in the limbs to adapt walking patterns to variations in the environment. During our last funding period we have: (1) examined how patterns of muscle activities and joint movements are changed when animals walk on surfaces in which the orientation of the gravitational vector is altered and (2) characterized the activities and effects of leg sensors that monitor the transition between the stance (foot on ground) and swing (foot lifted) phases of walking. These studies have shown that animals discretely adapt some elements of the walking pattern when the effect of the gravitational vector is changed. These adaptations most probably occur by using specific inputs from sense organs that detect load when a leg is placed on the ground. Further, the walking system uses inputs and local reflex mechanisms of joint angle receptors to insure that a stable base of support is maintained when a leg is lifted from the walking surface in swing. The latter types of sensory inputs may also be important in adjusting walking when the leg slips on an uneven or unstable substrate. These studies are forming the basis for our collaborative efforts with the group at Case Western Reserve University to incorporate our results into a functional controller for a robot leg.