2.5 Body lengths per
second. Rough Terrain. Here, the servos at the hips of a tripod of
legs are made to swing as the pistons are extended.
An impressive 2.5 body lengths per second is achieved and fairly
robust performance over obstacles that are the same height as the
"stomach" clearance is obtained.
This is mainly attributed to the swinging of the legs as well as
increased foot traction gained by padding the track and obstacles
with high-friction materials. The issues of foot traction is
raised: Cockroaches can achieve high traction due to their small
size and intricate leg design. Will our scaled-up robots be able
to do the same? Will they be able to operate with the same
magnitude of horizontal forces without slipping? Will they get
stuck in upward slopes?
Though the speed achieved is impressive, the behavior is still too
"hoppy" and not very "Groucho-like" [McMahon, et al. 1987]. Minisprawl is
observed to bottom-out, or crash, during the gait.
Playing the videos in slow motion (or one
frame at a time as one can do by using the arrow keys in Movie Player) one
can see that there is a galloping or bounding quality to the motion.