The stability of attitude of a robot can be recovered by an ambulation
control apparatus and an ambulation control method according to the
invention if it is lost in the course of a gesture for which the upper
limbs take a major role. The apparatus and the method obtain the pattern
of movement of the entire body for walking by deriving the pattern of
movement of the loins from an arbitrarily selected pattern of movement of
the feet, the trajectory of the ZMP, the pattern of movement of the trunk
and that of the upper limbs. Therefore, according to the invention, a
robot can determine the gait of the lower limbs so as to realize a stable
walk regardless if the robot is standing upright or walking.
Particularly, if the robot is made to gesture, using the upper body half
including the upper limbs and the trunk while standing upright, it can
determine the gait of the lower limbs so as to make a stable walk in
response to such a gait of the upper body half.