Oscillation-Based Locomotion of a Spherical Robot Driven by Flywheels With Low Control Torque

This paper presents a spherical robot driven by flywheels with low control torque, which combines terrain adaptability with flexible steering capability. The robot's center of mass is located below the sphere center, enabling sustained oscillations on the ground. Meanwhile, by periodically swinging its heading from side to side, the robot walks forward, eventually achieving locomotion along a zigzag trajectory. The robot can accumulate energy via oscillation under flywheel excitation, reducing the torque requirement and enabling a small actuator to drive a relatively heavy system. Experiments validate the robot's locomotion performance across various scenarios. The proposed actuation scheme demonstrates balanced performance while achieving lower torque demand under comparable normalized conditions.