Research Of USV Parameter Identification Method

Unmanned Surface Vessel(USV)is one of the tools for searching and investigating ocean information.In recent years it is becoming gradually valued by various maritime powers.The USV needs to overcome outside interferences not known in advance and complete the tasks independently,which requires good Maneuverability,The Maneuverability Prediction becomes the premise that must be paid attention to in early design.In this article I have done the modeling using the method of system parameter identification attached with experiment data.First,I simplified the mathematical model of USV,ignoring the effect of heaving,Pitching and rolling motion.Only the forward movement,transverse drift and yaw motion are considered.The motion of the vessel is simplified to a horizontal plane motion with only three degrees of freedom and the K-T equation is deduced.We have performed real ship experiment on the ocean and extracted data sample from the experiment.We used three system identification methods to model the USV: First,determine the value of parameter K using rotation experiment.Then,the value of parameter T is calculated through Z-shape experiment and the known value of K.Finally,first order linear response model is obtained;The second method performed the parameter identification of first order and second order Response model to the USV based on Support vector regression.In this section,through optimizing an improved SVR with the regularization parameters and insensitive parameters,we use this SVR identification modeling and comparative analysis with the unmodified SVR;The third method performed parameter identification of first order and second order response model based on least squares support vector machines.Here I have also optimized the regularization parameters.According to the identification results of those methods,I selected one of the heading control models,then identified the rolling model based on the rolling data collected from the experiment.The vector propulsion anti rolling controller based on heading and rolling is designed with the combination of two kinds of identification models.Simulation test in wave disturbance conditions is performed under different conditions,the comparison results are given in the article.