Intermittent trot gait of a quadruped walking machine dynamic stability control of an omnidirectional walk

This paper discusses an algorithm to make a quadruped machine walk dynamically and omnidirectionally following a real-time command from an operator. To produce a smooth body motion at high speed locomotion, we introduced a new gait, named the “intermittent trot gait”, in which a four-leg-supporting phase and a two-diagonal-leg-supporting phase appear in orders. In this gait, the pitching and rolling motion of the body is suppressed to a lower level than that of the other gaits because the dynamic effects of the swinging legs almost cancel each other. To realize the intermittent trot gait, new algorithms to plan a landing point and body motion are discussed. A landing point is decided by considering an operator command and conversion to the standard leg formation. A body motion is planned to produce dynamic stability and to follow speed and direction commands. By using these algorithms, a mechanical vehicle TITAN VI can walk omnidirectionally, smoothly following a real-time operator command. The top speed is 1 m/sec on flat terrain and 125 mm/sec on 105 mm up and down over rough terrain