Antidisturbance Containment Maneuvering And Safe Collision Avoidance Of Multiple Underactuated Autonomous Surface Vehicles

The ocean harbors a vast amount of natural resources.The efficient exploration,exploitation,and protection of the ocean can provide a solid guarantee for the sustainable development of mankind.As a new kind of tool,autonomous surface vehicles(ASVs)can undertake a variety of ocean operations.In particular,the cooperation of multiple ASVs is able to significantly improve the efficiency,reduce operation cost,improve fault tolerance ability,and can find various valuable application in military and civil fields.In the key technology field of multiple ASVs,the cooperative control of multiple ASVs is one of hot and cutting-edge topics in recent years and attracts increasing attention.This thesis investigates the antidisturbance containment maneuvering and safe collision avoidance for multiple underactuated ASVs.The main works of this thesis are as follows:First,this thesis investigates the containment maneuvering control of multiple underactuated ASVs subject to model uncertainties and time-varying disturbances induced by wind,waves and ocean currents under fixed topology.Containment maneuvering controllers with a guidance-control structure are proposed.In the guidance level,a containment control scheme and an auxiliary variable method are employed to develop formation-containment maneuvering guidance laws such that a temporal-spatial decoupling formation-containment formation pattern is achieved,overcoming the challenge caused by the underactuation.Formation deviations are introduced in the distributed path parameter update law design such that preassigned formation patterns among multiple virtual leaders are achieved.In the control level,a strong command tracking antidisturbance kinetic control law based on a second-order extended state observer(ESO)is proposed to improve the antidisturbance performance of the containment maneuvering control.Based on the stability analysis,it is proven that the closedloop system is input-to-state stable,and all error signals are uniformly ultimately bounded.Simulation results verify the effectiveness of the proposed antidisturbance containment maneuvering controllers for multiple underactuated ASVs.Next,this thesis addresses the containment maneuvering control of multiple underactuated ASVs subject to fully unknown model parameters and time-varying disturbances under switching topologies.Containment maneuvering controllers with a communication-guidancecontrol structure under switching topologies are proposed.In the communication level,multipath-guided distributed containment motion generators are first proposed for generating reference points according to the underlying switching topologies.In the guidance level,guiding-vector-field-based guidance laws are designed such that the smooth switching of containment maneuvering control under switching topologies can be achieved.In the control level,a data-driven adaptive ESO by utilizing historical data is developed to estimate the unknown kinetics and unknown control input gains simultaneously.By using the proposed controllers,multiple underactuated ASVs are able to converge to the convex hull spanned by multiple virtual leaders under switching topologies regardless of fully unknown model parameters.Based on the stability analysis,it is proven that the closed-loop control system is input-to-state stable and the tracking errors are uniformly ultimately bounded.Simulation results verify the effectiveness of the proposed containment maneuvering controllers under switching topologies.Then,this thesis investigates the containment maneuvering control and safe collision avoidance of multiple underactuated ASVs with model uncertainties,time-varying disturbances,and stationary obstacle constraints in the absence of velocity sensors.Observer-based finitetime containment maneuvering and safe collision avoidance controllers with a guidance-control structure are proposed.In the guidance level,distributed finite-time guidance laws are designed based on an auxiliary variable method and artificial potential fields such that the collisions between ASVs and between ASVs and obstacles are avoided.In the control level,a third-order finite-time ESO is designed to estimate the unmeasured velocities and unknown kinetics.Then,finite-time antidisturbance kinetic control laws are devised based on the finite-time convergent observers and nonlinear tracking differentiators.It is proven that all error signals in the closedloop system are bounded,and the distributed containment maneuvering control is achieved in a finite time when ASVs are outside the collision avoidance region.Simulation results substantiate the effectiveness of the proposed observer-based finite-time containment maneuvering and safe collision avoidance controllers.Finally,this thesis addresses the containment maneuvering control and safe collision avoidance of multiple underactuated ASVs subject to stationary/moving obstacle constraints,input constraints,model uncertainties,and time-varying disturbances.Safety-critical antidisturbance containment maneuvering controllers with a nominee-optimization-control structure are proposed.In the nominal level,a fixed-time ESO is employed for estimating unknown kinetics,and nominal containment maneuvering control laws are proposed in a NorthEast-Down reference frame such that a containment maneuvering pattern is achieved.In the optimization level,input constraints and stationary/moving obstacle constraints are integrated into the optimized control law design,and a distributed quadratic optimization problem based on input-to-state safe control barrier functions(ISSf-CBFs)is formulated.A recurrent neural network based neurodynamic optimization approach is adopted to solve the optimization problem and optimal control laws are obtained in a finite time.In the control level,optimal control inputs are computed based on the optimal control laws,such that the collisions between multiple ASVs and between ASVs and stationary/moving obstacles are avoided.It is proven that the error signals in the closed-loop system are uniformly ultimately bounded,and the closed-loop multiple underactuated ASVs system is guaranteed for input-to-state safety.Simulation results are elaborated to substantiate the effectiveness of the proposed safety-critical antidisturbance containment maneuvering controllers.