Walking robot and method for controlling posture thereof

摘要

A walking robot having joints which move using a torque servo, a posture of the robot being stably controlled, and a method of controlling a posture of the robot. It is possible to maintain a stable angle of the upper body while keeping an erect posture and balance using the COG of the robot and the inclination and the direction of the upper body and the pelvis of the robot, even in an external variation including external force or an inclination angle of the ground. Even in a state in which terrain information is not known in advance, the robot may keep an erect posture in a direction of gravity. Even when a plane where the robot stands is gradually inclined, the postures of the upper body and the legs of the robot may be kept while actively changing the angle of the ankle joint.

主权项

1. A method for controlling a posture of a robot including an upper body, a pelvis link connected to a lower side of the upper body, a plurality of hip joint portions connected to a lower side of the pelvis link, a plurality of legs respectively connected to the plurality of hip joint portions, and a plurality of feet respectively provided for the plurality of legs, the method comprising:
computing, by a computer, a position of a current Center of Gravity (COG) of the robot; setting a position of a desired COG of the robot; computing, by a computer, an error between the set position of the desired COG and the computed position of the current COG; computing, by a computer, a force to be compensated for keeping balance of the robot using the computed error; distributing the computed force to the plurality of legs; computing, by a computer, joint torque of each of the legs in accordance with the distributed, computed force; and performing torque servo control using the computed joint torque, wherein the distributing of the computed force includes: computing distances between a point of the current COG of the robot projected on the ground and the plurality of feet; and enabling a leg closer to the point of the current COG of the robot projected on the ground to have a larger value, based on the computed distances.