New Riccati Velocity Controller of the Spherical Robot

For the spherical robot, an efficient and precise velocity controller suitable for different terrains is crucial. In this paper, a new Riccati controller with feedforward compensation based on Kalman observer (FKO-Riccati controller) with better control performance and stronger robustness is proposed for velocity control of the spherical robot. An accurate dynamic model of the robot is established. Based on the model, a Riccati controller with velocity tracking performance and a Kalman velocity observer are proposed, and the output is feedforward compensated. To verify the effectiveness of the proposed controller, a series of experiments were conducted using a spherical robot named Rotunbot. The simulations and experimental results show that no matter what terrain the robot was in, compared with the traditional PID controller, the FKO-Riccati controller had better control performance and stronger robustness, whether it was going straight or turning.