A control method, executed by a control device, controlling a robot comprising a wheel leg portion and a base portion, the wheel leg portion and the base portion comprising a plurality of joints, the method including obtaining motion information of the robot and motion information of a sphere placed on the base portion of the robot, determining, based on the motion information of the robot and the motion information of the sphere when passivity based control is performed on the sphere and the base portion, base control information for controlling the base portion and balancing the sphere on the base portion, determining, based on the base control information, a control torque for controlling each joint of the plurality of joints, and controlling each joint based on the corresponding control torque.

An electric trailer with regenerative braking is adaptive to both EV and ICE tractors, extending towing range of such vehicles, coordinating with performance characteristics of a tractor for maximum tractor-trailer efficiency. Differential electrical control of wheel drives provides enhanced performance safety and driving control. Embodiments optimize performance using real-time road conditions and terrain information. The trailer provides fail-safe operation in the event of system malfunction.