Reflexive responses to slipping in bipedal running robots

Many robot applications require traversing uneven or unmodeled terrain. This paper explores strategies for one class of difficult terrain: slippery surfaces. We evaluate several reflexive responses to a slip using a dynamically simulated, three-dimensional, bipedal robot. We explore two kinds of reaction strategies. One strategy continues the step, in which the slip occurred. The other lifts the slipping foot and repositions the legs for another attempt. The most successful strategy positions the legs in a fixed triangular configuration on the step following a slip.