On Finite-time Coordination Control Of Uncertain Heterogeneous Multiple-AUV Systems

With the development of science and technology and the increasing focus on ocean resources,the research on Autonomous Underwater Vehicle(AUV)system has made great progress in recent years,and has been widely applied in various fields such as data collec-tion,ocean detection and target tracking.When faced with the complexity and diversity of ocean missions,it is increasingly difficult for a single AUV system to meet the increas-ing mission demands.However,the multiple AUV systems can carry out different spatial location distribution and task allocation,and complete the task through the coordination and cooperation between each other,which has the advantages of high efficiency,strong robustness,wide range of tasks and others.Therefore,the cooperative control technology of multiple AUV system has become the research hotspot of relevant researchers in recent years.In addition,how to ensure that the system can quickly converge to the required accuracy within finite time is also a challenge for multiple AUV systems in engineering practice.In this dissertation,a series of research works are carried out to solve the cooper-ative control problems of multiple AUV systems include finite time rendezvous,tracking,formation and circumnavigation under the conditions of uncertain parameters,intermittent communication and unavailability of partial state information,etc.,including:1.The finite-time position tracking control algorithm of uncertain heterogeneous multiple AUV system with and without velocity information are studied.A distributed reduced-order observer is proposed to estimate the state of the leader when only partial follower AUVs can directly obtain the information of the leader.Aiming at the uncertain model parameters of AUV system,an adaptive algorithm is designed to estimate the model parameters.Furthermore,when considering the unavailability of the velocity information of the AUV system,an observer relying only on the position information is proposed to estimate all the state information of the AUV in a finite time.Then,a distributed finite time position tracking control protocol based on the above estimates is designed for the available and unavailable velocity information of the AUV system.The stability of the system is proved by Lyapunov theory,sliding mode control method and finite time stability theory,and numerical simulation experiments are carried out.2.The finite-time velocity-free rendezvous control algorithm and trajectory tracking control algorithm of heterogeneous multiple AUV system under intermittent communica-tion is studied.For the rendezvous control problem,a distributed observer is proposed for each follower AUV to estimate its own state information.Then,a finite time rendezvous control protocol is designed based on observer.For the trajectory tracking control prob-lem,two distributed observers based on intermittent communication are proposed for each follower AUV to estimate the state information of leader and its own.Then,an observer-based finite-time trajectory tracking control protocol is designed.The stability of the sys-tem is proved by Lyapunov theory,intermittent communication mechanism and finite time stability theory,and numerical simulation experiments are carried out.3.The finite-time formation-circumnavigation switching control algorithm of hetero-geneous multiple AUV system under intermittent communication is studied.A distributed finite time observer based on intermittent communication is designed to estimate the state information of the target when only partial AUVs can obtain the target information in-termittently.Then,an observer-based finite-time formation-circumnavigation switching control protocol is designed.The effectiveness of the algorithm is proved by Lyapunov theory,intermittent communication mechanism and finite time stability theory,and nu-merical simulations are carried out.4.The finite-time multiple circles formation-circumnavigation switching control algorithm of heterogeneous multiple AUV system with an intermittent communication mechanism among partial individuals is studied.Aiming at the multiple circle orbit prob-lem of multiple AUV system,the clustering idea is introduced to divide all AUVs into groups.Then,a distributed observer under intermittent communication is proposed for each cluster leader to estimate the information of the target,and another observer is pro-posed for each cluster follower to estimate the state of leader.Finally,the observer-based finite-time multiple circles formation-circumnavigation switching control protocol is de-signed.The effectiveness of the algorithm is proved by Lyapunov theory,intermittent communication mechanism and finite time stability theory,and numerical simulations are carried out.