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Research On Task Driven Tracking Control Method For Dynamic Positioning Vessel

Posted on:2015-05-14Degree:DoctorType:Dissertation
Country:ChinaCandidate:A H ZhangFull Text:PDF
GTID:1312330518472870Subject:Control theory and control engineering
Abstract/Summary:PDF Full Text Request
Because of excellent mobility,flexibility and freedom from the ocean depth limit,dynamic positioning(DP)vessels have more and more widely used in marine engineering.And as the basic function of the DP control system,the tracking control mainly include four tracking tasks,they are low speed path tracking,high speed path tracking,target tracking,special tracking.DP vessels will appear different dynamic performance for different tracking tasks,so that a fixed controller is difficult to ensure good response to all of tracking tasks.However,and most of the literature published abroad only studied for one or two tasks at present,they failed to consider the dynamic responses of a DP vessel in the course of performing different tasks.Form the perspective of improving resource utilization,increasing adaptability and improving the level of automation,the work of the tracking control strategy which can deal with requirements of tracking tasks set for DP vessel automatically is neccassary,and has important theoretical significance and engineering value.The tracking control problem for DP vessels is studied deeply in this paper,and takes the tracking control decision making into account for the first time.We establish the hierarchical task driven Petri nets model of DP vessels tracking control system through proposing a concept called task driven tracking control,mathematical description of the tracking control process is given,which is a basis for deep study of guide algorithms and control algorithms in the real time control layer of the Petri net model.The main work includes following aspects:Firstly,the dynamic positioning vessel tracking control is divided into low speed path tracking,high speed path tracking,target tracking and special tracking.Through the layer division of the tracking control system and the analysis of different tasks goals,tracking control system is a typical hybrid system is known,and by using vessel operational condition(VOC)method,the concept of task driven for the tracking control problem of DP vessel is given,the task driven hierarchical Petri net model is established by analysis of the mapping logic between discrete task layer and real time control layer.Then,on the basis of open loop guidances algorithm,for low speed path tracking control,by considering both infections from nonlinear damping and Coriolis centripetal forces,and using a semi-global exponential stability observer to estimate unmeasured state variables,we propose a semi-globally uniformly exponentially stable observer control algorithm to solve the problem that only the heading and position information is available in controller design.Then to avoid calculate inflation in backstepping,and deal with the uncertainty activized by operation equipments in the special tracking task,an adaptive dynamic surface control algorithm is proposed by using the desired values from the proposed relative distance guidance algorithm,and uniformly asymptotically bounded of the controller is proved.And,on the basis of research on the role of Line of Sight(LOS)guidance algorithm for DP vessels tracking control,to get the desired surge speed and heading for the high speed path tracking task,SFLOS closed loop guidance algorithm is designed.An adaptive backstepping controller without restriction of fully actuated character and underactuated character is designed for high speed path tracking,and by integrating closed loop guidance algorithms,on the basis of SFLOS,the closed loop cascaded guided control algorithm is proposed for high speed path tracking task of DP vessels.Finally,to deal with target tracking task with only the current positon and heading of the target known,the Constant Bearing(CB)closed loop guidance algorithm is designed to get the desired desired surge speed and heading,and the closed loop cascaded guided control algorithm is designed for high speed target tracking.To ensure the stability of switching process between underactuated tracking and fully actuated tracking,a globally stable switching control algorithm for target tracking task is proposed by introducing a speed switching function,.Meanwhile,simulation study of the control algorithms are carried out,and based on these control algorithms desgined in this paper,the correctness of task driven Petri net model of DP vessel tracking control is verifed by simulation results.
Keywords/Search Tags:dynamic positioning vessel, tracking task, task driven, Petri net, guided control, observer control
PDF Full Text Request
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