A floor shape estimation system for a legged mobile robot, in particular a biped
walking robot, which estimates a foot-to-foot floor inclination difference based
on at least a control error of the total floor reaction force's moment and corrects
a feet compensating angle based on the estimated value. Further, the system estimates
a foot floor inclination difference based on at least a control error of the foot
floor reaction force about a desired foot floor reaction force central point and
corrects a foot compensating angle based on the estimated value. Furthermore, it
determines whether it is in a situation where the accuracy of estimation is liable
to degrade based on at least a time of the gait of the robot and when it is in
the situation, the system interrupts the estimation. With this, the system can
accurately estimate the shape of floor with which the robot is in contact.
