Patent ID: 8473102
Filing Date: 2013-06-25
Classification: B62D

Abstract:
1. A robot controller that drives joints of a robot having a plurality of legs to make the robot walk, the robot controller being configured to: determine a permissible range for a trunk vertical position of the robot based on measured environmental parameters, the measured environmental parameters being information of an environment around the robot; and make the robot walk based on measured posture parameters representing a posture of the robot so that the trunk vertical position remains within the permissible range, wherein in order to adjust the trunk vertical position within the permissible range, a trunk vertical position reference input, which is a target value of the trunk vertical position of the robot, is set to the lower bound when the trunk vertical position calculated based on the measured posture parameters is smaller than a lower bound of the permissible range, whereas the trunk vertical position reference input is set to the upper bound when the trunk vertical position is larger than an upper bound of the permissible range, and wherein the measured posture parameters include a thigh angle, a knee angle, and an idling-leg angle of the robot, wherein a target value of a knee absolute angle, which is a sum of a thigh angle and a knee angle of the robot, is used as a knee absolute angle reference input, and the knee absolute angle reference input is a function of the thigh angle of the robot, and the robot controller being further configured to: obtain the knee absolute angle reference input by subtracting a product of a thigh length and the thigh angle of the robot from the trunk vertical position reference input; divide the subtracted value by a shank length; and apply arccosine function to the divided value.