Two-phase discontinuous gaits for quadruped walking machines with a failed leg

A fault-tolerant gait of multi-legged robots with static walking is a gait which can maintain gait stability and continue its walking against an occurrence of a leg failure. This paper proposes two-phase discontinuous gaits as a new fault-tolerant gait for quadruped robots suffering from a locked joint failure, which prevents a joint of a leg from moving and makes it locked in a known place. By comparing with previously developed one-phase discontinuous gaits, it is shown that the proposed gait has great advantages in gait performance such as the stride length and terrain adaptability. As an application of the proposed gait, the gait algorithm for ditch crossing and avoidance of quadruped robots with a failed leg is presented and illustrated by simulated figures.