Direction and Trajectory Tracking Control for Nonholonomic Spherical Robot by Combining Sliding Mode Controller and Model Prediction Controller

TL;DR

This paper presents a novel control framework combining a hierarchical sliding mode controller and model predictive control for precise direction and trajectory tracking of nonholonomic spherical robots, validated through hardware experiments.

Contribution

The study introduces a new hierarchical sliding mode controller and an integrated control framework for spherical robots, enhancing stability and response speed.

Findings

The proposed controllers achieve quick response and strong stability.

Hardware experiments confirm the effectiveness of the control framework.

The framework eliminates the need for stability and dynamic constraints in MPC.

Abstract

Spherical robot is a nonlinear, nonholonomic and unstable system which increases the difficulty of the direction and trajectory tracking problem. In this study, we propose a new direction controller HTSMC, an instruction planning controller MPC, and a trajectory tracking framework MHH. The HTSMC is designed by integrating a fast terminal algorithm, a hierarchical method, the motion features of a spherical robot, and its dynamics. In addition, the new direction controller has an excellent control effect with a quick response speed and strong stability. MPC can obtain optimal commands that are then transmitted to the velocity and direction controller. Since the two torque controllers in MHH are all Lyapunov-based sliding mode controllers, the MHH framework may achieve optimal control performance while assuring stability. Finally, the two controllers eliminate the requirement for MPC's stability and dynamic constraints. Finally, hardware experiments demonstrate the efficacy of the HTSMC, MPC, and MHH.