Kinematic and dynamic calibration methods for legged robots with force-controlled joints

A robot with kinematic calibration, comprising:

• a body comprising a plurality of links and force-controlled joints, wherein the links include a pelvis link and the joints include a pair of ankle joints each positioning a foot;
• an angle sensor associated with each of the joints;
• an inertial measurement unit (IMU) provided on the pelvis link;
• and
• a processor running a kinematic calibration module,
• wherein the kinematic calibration module processes angle measurements provided by the angle sensors and data generated by the IMU, wherein the angle measurements and IMU data is collected during movement of the body through a number of poses,
• wherein the feet are flat and in contact with a planar support surface during each of the poses to enforce a kinematic constraint during data collection,
• wherein the kinematic calibration determines an angle offset value for each of the joints based on the IMU data and the kinematic constraint, and
• wherein the kinematic constraint further includes aligning the feet such that the feet are side-by-side and parallel or arranged toe-to-heel during each of the poses.

A system for calibrating a humanoid robot, comprising:

• memory storing angle measurements from a set of joints of a humanoid robot, the angle measurements being provided by angle measurement sensors mounted on the humanoid robot operating during movement of the humanoid robot through a plurality of poses while enforcing a kinematic constraint, wherein the humanoid robot has two feet and the kinematic constraint comprises maintaining soles of the feet in contact with a horizontal planar surface;
• memory storing data output from an IMU mounted on the humanoid robot, the IMU data being output from the IMU being collected during the movement of the humanoid robot;
• and
• a processor performing kinematic calibration by processing the angle measurements and the IMU data to identify angle offset values for each of the joints.