Development of a Humanoid Dual Arm System for a Single Spherical Wheeled Balancing Mobile Robot

This paper presents a new 14-DoF dual manipulation system for the CMU ballbot. The result is a new type of robot that combines smooth omnidirectional motion with the capability to interact with objects and the environment through manipulation. The system includes a pair of 7-DoF arms. Each arm weighs 12.9 kg, with a reach of 0.815 m, and a maximum payload of 10 kg at full extension. The ballbot's arms have a larger payload-to-weight ratio than commercial cobot arms with similar or greater payload. Design features include highly integrated sensor-actuator-control units in each joint, lightweight exoskeleton structure, and anthropomorphic kinematics. The integration of the arms with the CMU ballbot is demonstrated through heavy payload carrying and balancing experiments.