Automatic Generation of Humanoid's Geometric Model Parameters

This paper describes a procedure that automatically gen-erates parameters for the geometric modeling of kinematic chains. Theconvention of modeling used is the Denavit Hartenberg convention mod-ified by Khalil Kleinfinger, noted DHKK. The procedure proposed herehas two advantages. First the user does not need to calculate the geo-metric parameters by himself. He simply has to give the directions of thesuccessive joint axes, and for each joint axis, a point that belongs to theaxis. The second advantage deals with the use of model-generic matricesfor the beginning and the end of the kinematic chains, and not only forthe joint axes. This prevents the user from doing specific calculation toconnect the joint matrices derived from the model with the initial andthe final coordinate frames of the chain. Due to its unified formalism,the procedure allows to save time when the kinematics of the robot hasto be changed. This paper includes the application of this procedure tothe geometric modeling of legs and arms of two versions of the NAOhumanoid robot, the one used in the RoboCup 3D Simulation League,and the other one used in the RoboCup Standard Platform League.