Modeling, Identification and Compensation of Friction in Solo12 Quadruped Robot

The accuracy of the dynamic model of a robot plays an important role for robots performing highly dynamic tasks. Quadruped robots are often performing highly dynamic tasks and in order to be able to do that, fine and precise control of all joints is necessary. Friction compensation can play an important role in accomplishing this. A friction identification procedure for quadruped legged robots is presented in this paper. The procedure consists of a predefined joint motion that minimizes the joint coupling and collects the necessary data for friction estimation. Using the identified friction terms, a PD torque controller with friction compensation was implemented. The identification procedure and the torque controller are tested on a Solo12 quadruped robot using MuJoCo simulation software and on the real robot.