كنترل پيش بيني براي ربات زير آبي خودگردان با استفاده از رويتگر اختلال

چكيده انگليسي :

Model Predictive Control for Autonomous Underwater Vehicle by using Disturbance Observer Mohammad Falahatian m falahatian@ec iut ac ir Date of Submission Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan Iran Degree M Sc Language FarsiSupervisors Javad Askari j askari@cc iut ac ir Yadollah Zakeri yzakeri@cc iut ac irAbstract Nowadays underwater vehicles are important part of shore and offshore industries These vehicles havesignificant role in scientific research commercial and military applications such as submarineobservations structural inspection inspection of underwater pipelines and cables mapping drillingoperations and etc Although remotely operated vehicles ROV have been employed for detection andtracking their range of operation is constrained by the length of the tether Furthermore the need for asupport vessel and an ROV operator adds to the cost of monitoring operation One way to circumvent theseproblems is to render the autonomous underwater vehicles AUV that is they execute the task withminimal human intervention It is obvious that the operation of these robots depends on good performanceof their control and guidance system There are some problems to design the control system of these robotssuch as nonlinearity and interaction of motion equations in different directions and disturbances fromenvironment In this thesis a control system in directions of heading and depth is designed for autonomousunderwater vehicle with nonlinear model predictive control based on disturbance observer Therefore inbeginning nonlinear and multivariable dynamic equations of robot motion in six degree of freedom forREMUS model are presented Dynamic equations are converted into two single input single outputsubsystems to design the control system This conversion can be done by this assumption that theinterferences between movements in other directions are disturbance On this basis nonlinear modelpredictive control is designed by assumption that the states and the disturbance created from interferencesbetween movements in other directions is available The prediction model used in the controller design iscarried out via Taylor series expansion In order to estimate disturbance two disturbance observers areintroduced separately A basic idea in the design of the first observer estimator is to modify the estimationby the difference between the estimated output and the actual output But second observer is based onsliding mode observer In this observer disturbance is estimated by using estimation the state In fact thenonlinear model predictive controller with the sliding mode observer uses partial state feedback The abilityof this controller to track reference heading and depth in each subsystem and also the ability of twoobservers to estimate the disturbance are shown by simulation Also the performance of this controller tocontrol the six degree of freedom equations is shown Guidance through waypoints is common for smallautonomous marine vehicles Guidance by the line of sight the basic waypoint guidance algorithm is verysimple computationally inexpensive and flexible to sudden changes in the desired path specification Eventually in order to track the waypoints in surface by autonomous underwater vehicle a guidancealgoritm is presented Nonlinear model predictive controller with disturbance observer is used to track thereference commands generated by the guidance algorithm Combination of mention guidance andcontroller in order to track the waypoints is tested in six degree of freedom equations by simulation Keywords

فلاحتيان، محمد

كنترل پيش بيني براي ربات زير آبي خودگردان با استفاده از رويتگر اختلال

ديناميك , كنترل سمت و عمق , رويتگر اغتشاش , سيستم هدايت