Xian Yang, Jing Yan, Tianming Chen, Xiaoyuan Luo, Xinping Guan
Human-on-the-loop (HOTL) systems are recognized as a practical tool for enabling underwater vehicles to track reference trajectories effectively. However, communication constraints inherent in underwater environments make it challenging to accomplish this tracking task. This article addresses the event-triggered tracking issue for an underwater underactuated vehicle (UUV) in the presence of communication constraints. First, a single event-triggered transmission policy is designed to transmit the collected UUV state information to a control center. Based on this policy, a nonlinear tracking controller is developed to drive the UUV toward the desired trajectory. To further enlarge the triggering interval and reduce communication energy consumption, a hybrid event-triggered transmission policy is also proposed. Subsequently, a nonlinear tracking controller is developed using feedback linearization. For both developed tracking controllers, a hybrid network technique is employed to establish the event-triggered conditions during the communication process. Additionally, the closed-loop stability of the tracking controllers is analyzed in terms of both jump and flow dynamics. Finally, simulation and experimental results are presented to validate the effectiveness of the proposed approach. It is demonstrated that the developed tracking solution ensures system stability while reducing energy consumption.