Collision-Free Connectivity Topology Switching and Maintenance for Autonomous Underwater Vehicles

In the collaborative application of multiple autonomous underwater vehicles (AUVs), collision avoidance is essential for ensuring the physical safety of AUVs, while a specific connectivity topology is required for information exchange. This dual requirement presents challenges for controller synthesis. Thus, this study focuses on collision-free connectivity topology switching and maintenance during collaborative missions. For the primary control goal of reaching predefined locations, a backstepping-based controller is designed to ensure system stability. Collision avoidance is achieved through the application of high-order zeroing control barrier functions (ZCBFs), which guarantee the forward invariance of the desired safety set. To facilitate high-bandwidth information exchange, establishing a specific connectivity topology within an effective range is necessary. High-order finite-time convergence control barrier functions (FCBFs) are employed to form new topologies within finite time and then maintain the forward invariance of the desired set. The controller is synthesized using quadratic programming optimization, incorporating collision-free topological constraints and minimally modifying the backstepping-based controller. Numerical simulations and field experimental results demonstrate the effectiveness of the proposed controller, showing that topology switches faster than in existing studies while ensuring collision avoidance under disturbances.