Floor shape deducing device for legged mobile robot

A system for controlling a legged mobile robot having at least a body and a plurality of legs each connected to the body through a first joint and having a foot connected to its distal end through a second joint, the system having a compliance mechanism which deforms in response to a floor reaction force acting from a floor with which the foot is in contact and joint displacement means which displacing the first and second joints such that the foot follows a desired position and/or posture, comprising:

• a. inclination detection means for detecting an inclination of the body relative to a vertical direction;
• b. walking environment foot position and/or posture calculating means for calculating a position and/or posture of the foot in a walking environment including the floor with which the foot is in contact, based on an actual and/or desired position and/or posture of the foot and the detected inclination;
• c. deformed foot position/posture calculating means for calculating the position and/or posture of the foot with deformation of the mechanism in response to the floor reaction force acting from the floor in the walking environment using a mechanism compliance model which models the compliance mechanism;
• and
• d. floor shape estimation value calculating means for calculating a floor shape estimation value indicative of shape of surface of the floor with which each foot is in contact and indicative of a relationships therebetween;
• wherein the floor shape estimation value calculating means includes:
• e. estimation interrupting means for determining whether it is in a situation where the calculation of the floor shape estimation value should be interrupted, and for continuing the calculation of the floor shape estimated value when it determines that it is not in the situation.