Modeling of Autonomous Underwater Vehicles with Multi-Propellers Based on Maximum Likelihood Method

Abstract

The hydrodynamic characteristics of multi-propeller autonomous underwater vehicles (AUV) is usually complicated and it is difficult to obtain an accurate mathematical model. A modeling method based on CFD calculation and maximum likelihood identification algorithm is proposed for this problem. Firstly, rough hydrodynamic parameters of AUV hull are obtained by CFD calculation. Secondly, on the basis of rough parameters, a maximum likelihood identification algorithm is proposed to adjust the parameters and improve the model precision. Besides, the method to improve the convergence of identification algorithm is analyzed by considering the characteristics of AUV model structure. Finally, the identification algorithm and identification results were validated with experimental data. It was found that this method has good convergence and adaptability. In particular, the identification results of turning force and torque parameters are highly consistent in different identification experiments, which indicates that this method can well extract the maneuvering characteristics of AUVs, thus contributing to the controller design of AUVs. The research of this paper has potential application for the modeling and control of multi-propeller AUVs.

Research on the Heading Control of Underwater Vehicle Under Hover Condition

“…In previous research [24], we found that additive uncertainty was suitable for describing steering dynamic in hover state.…”

“…(36) Due to the influence of water velocity, wake coefficient and thrust reduction coefficient, it is difficult to obtain accurate mathematical model. In our previous study, CFD calculation and parameter identification were used to obtain the parameters [24]. It was found that there were obvious differences in calculated parameters within different experimental samples.…”

“…(2) In our previous study [24] , it was found that the complex flow field around underwater vehicle during turning motion under hover condition, which affected the operation efficiency of the propeller, and it was difficult to obtain accurate mathematical model, thus affecting the performance of the control algorithm.…”

Use of a nonlinear controller with dynamic couplings in gains for simulation test of an underwater vehicle model

“…Problems concerning the modeling of marine vehicles have been considered in many works, among others in the literature. 1,[31][32][33][34] Since the aim of this article is to show usefulness of the equations of motion expressed in the GVC, the model should be general but also simplified enough to be suitable for the design of vehicle controller. In the proposed approach, the analysis of the dynamics and the influence of couplings are performed using the description in quasivelocities, which are obtained from the decomposition of the inertia matrix.…”

Mini-AUV Hydrodynamic Parameters Identification via CFD Simulations and Their Application on Control Performance Evaluation

“…Recent publications provide evidence of the efforts to improve hydrodynamic parameters estimation techniques, emphasizing the increasing importance of the implementation of computational resources. In [ 18 ], a maximum likelihood identification algorithm in conjunction with CFD calculations is proposed and validated via experimentation. On the other hand, the hydrodynamic parameters are treated as a function of the angular position in the performance of sharp maneuvers, as exposed in [ 19 , 20 ].…”