Simulation Of Underwater Vehicle Research Articles

Design and Implementation of Autonomous Underwater Vehicle Simulation System Based on MOOS and Unreal Engine

An effective autonomous underwater vehicle (AUV) simulation system can greatly improve development efficiency and reduce the cost and risk of actual equipment operation. In this paper, a comprehensive simulation system is developed using Mission Oriented Operating Suite (MOOS) and Unreal Engine 4 (UE4). The former provides an open-source development framework and application components, which are widely used in the field of underwater robots. The latter is a well-known game development engine that has realistic effects and various plugins. As far as we know, there are few simulation systems based on MOOS and UE4. Moreover, a modular architecture for the simulation system is designed and implemented in the paper. The developed system consists of four subsystems, including the simulation editing and controlling subsystem, shore-based operation subsystem, simulation engine subsystem, and three-dimensional (3D) visualization subsystem. These subsystems have modular characteristics and independent functions and communicate with each other through network sockets. Through the system, users can customize simulation scenarios, send missions and control simulation progress from the graphic user interface. And the system can be used in operation training, software testing, algorithm verification of AUV, etc.

An Autonomous Underwater Vehicle Simulation With Fuzzy Sensor Fusion for Pipeline Inspection

Underwater pipeline inspection is an important topic in off-shore subsea operations. Remotely operated vehicles (ROVs) can play an important role in multiple application areas including military, ocean science, aquaculture, shipping, and energy. However, using ROVs for inspection is not cost-effective, and the fixed leak detection sensors mounted along the pipeline have limited precision. Although the cost can be significantly reduced by applying autonomous underwater vehicles (AUVs), the unstable current, low visibility, and loss of GPS signal make the navigation of AUVs underwater very challenging. Previous studies have been conducted on coordinate-based, vision-based, and fusion-based navigation algorithms. However, the coordinate-based algorithms suffered from the denial of GPS signals while the vision-based methods typically relied on terrain and landscape knowledge that required collection prior to the mission. As a result of these issues, a navigation system for an AUV that incorporates vision and sonar sensors is presented in this article. In a robot operating system (ROS)/Gazebo-based simulation environment, the AUV had the ability to find and navigate toward the pipeline and continuously traverse along its length. Additionally, with a chemical concentration sensor mounted on the AUV, the system demonstrated the capability of inspecting the pipeline and reporting the leak point with a resolution of 3 m along the pipeline.

Autonomous Underwater Environment Perceiving and Modeling: An Experimental Campaign With FeelHippo AUV for Forward Looking Sonar-Based Automatic Target Recognition and Data Association

Seabed inspection is one of the most sought-after applications for autonomous underwater vehicles (AUVs). Acoustical sensors, such as side-scan sonars and forward-looking sonars (FLSs), are commonly favored over optical cameras to carry out such a task. Indeed, sonars are not influenced by illumination conditions and can provide high-range data. However, due to the lack of features and low resolution, acoustical images are often hard to interpret with conventional automatic techniques, forcing human operators to analyze thousands of collected images to identify the so-called objects of potential interest (OPIs). In this article, we report the development of an automatic target recognition (ATR) methodology to identify and localize OPIs in FLS imagery. Such detections have been then exploited to realize a virtual world model with the probabilistic multiple hypothesis anchoring data association and model tracking algorithm. Distinct models of convolutional neural networks have been trained with a data set acquired in May 2019 at the Naval Support and Experimentation Centre (Centro di Supporto e Sperimentazione Navale—CSSN) basin in La Spezia, Italy. The ATR strategy has been successfully validated offline with the data gathered in October 2019 in the same site where the seabed targets were replaced and relocated. As regards the world modeling technique, it has been preliminarily tested on a simulated scenario built upon unmanned underwater vehicle Simulator. Finally, both the ATR and world modeling systems were on-field tested in October 2020 at the CSSN basin in a multivehicle architecture by employing an acoustical channel between FeelHippo AUV and an autonomous moving buoy.

Simu2VITA: A General Purpose Underwater Vehicle Simulator.

This article presents an Unmanned Underwater Vehicle simulator named Simu2VITA, which was designed to be rapid to set up, easy to use, and simple to modify the vehicle’s parameters. Simulation of the vehicle dynamics is divided into three main Modules: the Actuator Module, the Allocation Module and the Dynamics Model. The Actuator Module is responsible for the simulation of actuators such as propellers and fins, the Allocation Module translates the action of the actuators into forces and torques acting on the vehicle and the Dynamics Module implements the dynamics equations of the vehicle. Simu2VITA implements the dynamics of the actuators and of the rigid body of the vehicle using the MATLAB/Simulink® framework. To show the usefulness of the Simu2VITA simulator, simulation results are presented for an unmanned underwater vehicle navigating inside a fully flooded tunnel and then compared with sensor data collected when the real vehicle performed the same mission using the controllers designed employing the simulator.

The conception and exploration of the underwater vehicle simulator

In this paper, a new type of underwater vehicle simulator is proposed. The underwater vehicle simulator adopts capsule prefabrication structure and can be carried on UUV Each UUV can be loaded with multiple underwater vehicle simulator capsules. After sailing to the predetermined location, long-distance delivery is carried out. After the underwater vehicle simulator is fully charged and expanded, the underwater vehicle simulator cluster is formed to achieve tactical purposes such as confusing and inducing enemies in quantity, orientation and deployment. The technology can be applied to the new generation of underwater vehicle safety defense system, and can be popularized and applied to other weapon systems. It has great military, political and national defense significance and has broad application prospects.

Research on UE4 - based Visualization Simulation of Underwater Vehicle Polar Region Sailing

With the continuous exploration of polar sea areas, the reliability and safety of polar navigation have become the top priority. Due to various influencing factors in the polar region, including sea ice, ocean currents, geomagnetism, gravity, etc., navigation equipment in the polar region cannot achieve the performance of the mid-low latitude region. Because of the limitation of the actual ship entering the polar region, the performance of navigation system in polar region cannot be fully verified. It is difficult to verify the performance of equipment on a real ship. In order to reduce the cost of the experiment while ensuring the accuracy of the verification and making the simulation training system available at the same time. Based on UE4(Unreal Engine4) to design a virtual 3D visual simulation platform of underwater vehicle that is able to simulate the six-degree-of-freedom(6-dof) motion of the underwater vehicle and verify the performance of navigation equipment in polar region. Verify the virtual simulation platform is able to simulate the movement of underwater vehicle in the virtual polar sea and realize the operation training simulation of underwater vehicle.

G1500402 水中ロボットの数値シミュレーションに関する研究

G1500402 水中ロボットの数値シミュレーションに関する研究

Study of autonomous underwater vehicle wave disturbance rejection in the diving plane

Autonomous underwater vehicles operating near the sea surface are subject to wave disturbances in their motion, which can affect severely the data acquisition during the vehicle motion. Bathymetric maps, for example, may suffer a big loss in quality due to such kind of disturbances that can impose oscillations in the vehicle depth and attitude. This article describes a controller structure for compensating the wave disturbances in the vertical plane for a torpedo-like autonomous underwater vehicle, based on a modified version of the linear quadratic Gaussian with loop transfer recovery control combined with a wave filter. The proposed methodology uses additional to the classic linear quadratic Gaussian with loop transfer recovery design the measurement of non-controlled states, such as the pitch rate and heave velocity, in the control action. The wave disturbances were filtered away by a shaping filter fitted to the sea spectrum, and the sensor signals were integrated by an extended Kalman filter. The proposed control methodology was tested against the classical linear quadratic Gaussian with loop transfer recovery controller in a 6-degree-of-freedom non-linear autonomous underwater vehicle simulator, producing a better performance in most demanding conditions such high wave crests. The tests also revealed the impact of the hydroplane geometry on the controller performance, which should not be underestimated by the autopilot designer.

Automated Ballast Tank Control System for Autonomous Underwater Vehicles

Autonomous underwater vehicles (AUVs) are frequently used for deep-water ocean applications such as surveying and cable laying, where accurate control of vehicle depth and attitude is needed. The water level in the onboard ballast tanks is typically manually set for neutral buoyancy before each mission, while the vehicle is on the surface. The ballast tank contents are not normally adjusted to control vehicle depth and orientation while the AUV is in operation. As a result, vehicle trajectory and orientation is exclusively controlled using the vehicle's control surfaces during a mission. The challenges with controlling the depth and trim of an underwater vehicle include nonlinear hydrodynamic forces, as well as inherent time delays (latencies) associated with water tank level changes and valve adjustments. Furthermore, small changes in the location of the vehicle's center of gravity (i.e., due to the deployment of the AUV's payload equipment) can reduce the control authority of the AUV's control surfaces. To meet these challenges, this paper proposes two unique variable ballast system (VBS) control approaches. The first proposed VBS controller changes the weight of the AUV to help control vehicle depth and vertical (inertial) velocity. The second proposed VBS controller attempts to shift the center of gravity <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sup> <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">G</i> along the body-fixed <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</i> -(longitudinal)-axis to reduce depth and pitch angle error while restoring control authority to the bowplane and sternplane deflection fins. The ballasting system consists of two water tanks positioned aft and forward of amidships. The ballast tanks are then automatically filled or emptied of ocean water as desired. Numerical simulations have been carried out on a 2-D underwater vehicle simulator to test and compare the performance of the proposed ballast and fin deflection control systems. The simulation results show that, for the assumptions and conditions tested, the proposed controllers are capable of achieving a setpoint depth and pitch angle with minimal error by effectively utilizing the ballast tanks and deflection fins. As a result, the work presented in this paper helps increase the autonomy of large AUVs on long-duration missions.

Maneuvering control simulation of underwater vehicle based on combined discrete-event and discrete-time modeling

When designing or acquiring underwater vehicles such as submarines and torpedoes, it is necessary to predict their performance precisely and perform tests repeatedly using modeling and simulation at both the engineering level and the tactical engagement level. For simulation performed for analysis purposes at the engineering level, which requires a considerable amount of computation power, a discrete-time system simulation that computes significant values at every single unit time using the established mathematical model or engineering model is mainly employed. To simulate a complex or complicated task such as a traffic analysis or tactical measure of effectiveness (MOE) analysis at the engagement level, it is appropriate to use a discrete-event system simulation that causes transition between model states through the triggering of events on the basis of the passing of messages between simplified mathematical models coupled in various ways. In this paper, we studied a maneuvering control of underwater vehicle from the perspective of a combined discrete-event and discrete-time system simulation; the simulation model is established on the basis of discrete-event system specification (DEVS) formalism, which is a representative modeling formalism of a discrete-event system simulation. In detail, the simulation includes DEVS modeling implementations of simulation execution time control and discrete-time step size control in real time at the time of performing a discrete-time system simulation for the purpose of three-dimensional visualization or carrying out a performance analysis using the DEVS model. This hybrid approach makes possible to build a simulation-based expert system which supports the decision making for the acquisition of an underwater vehicle.

Torpedo evasion simulation of underwater vehicle using fuzzy-logic-based tactical decision making in script tactics manager

An underwater vehicle such as a submarine or a torpedo is a complex and complicated weapon system composed of various systems and subsystems. Usually, it takes around 10years, a substantial amount of money, and many research and development resources to complete the development of an underwater vehicle, right from the concept design to the mass production. Recently, in order to reduce the number of trial-and-error instances required for verifying the operation of an underwater vehicle, modeling and simulation (M&S) has been investigated and applied to an engineering-level simulation to analyze the performance of a system and a subsystem and to an engagement-level simulation to analyze the tactical and operational effectiveness. In this paper, we introduce a method for applying fuzzy logic to the tactical decision making of an underwater vehicle in an engagement-level simulation. In the scenario of an engagement between a light torpedo pursuing a submarine and the submarine attempting to evade the attack, the evasion methods for the submarine are modeled in fuzzy logic after tacticalization. For the simulation, we modeled a light torpedo and a submarine on the basis of DEVS (Discrete Event System Specification). Further, when a tactical decision had to be taken, the submarine model calls the tactics manager implemented outside of the model and passes its own state variables, which are necessary for tactical decision making, to the tactics manager. The tactics manager used in the tactical decision making process supports Lua and the Python scripting languages and is self-implemented. The tactics description of the submarine was implemented using Python scripting grammar and stored as a Python file (∗.py) to be inputted to the tactics manager. As the simulation results, we present the implemented fuzzy Python tactic description file of the submarine evasion tactics and the possibilities of submarine survival according to the tactics as a comparison. Finally, as the fundamental research on the application of artificial intelligence to the tactical decision making method of the model used in the engagement-level simulation, this work suggests the fuzzy-based tactics description method and presents the detailed procedures for the various actions, and their adopting effectiveness.

Numerical Simulation of the Overall Flow Field for Underwater Vehicle with Pump Jet Thruster

The flow field numerical simulation of underwater vehicle with pump jet thruster was performed using the commercially available CFD software FLUENT based on the Reynolds averaged Navier Stokes Equations and k-epsilon RNG turbulence model. Multiple reference frames (MRF) was used to associate the interior flow field of the pump jet thruster and exterior flow field of the underwater vehicle. Validity of the CFD model is verified using data from experiment. Characteristic of the overall flow field was obtained and pressure distribution of the propulsion was also given. The simulation results could be regarded as an important reference in the optimal design of pump jet thruster and the hydrodynamic characteristics of underwater vehicle.

An Underwater Vehicle Simulator with Immersive Interface using X3D and HLA

Training war fighters how to maneuver a submarine is very important, but the use of real submarines in such training is expensive and hindered by regional and temporal limitations. Modeling and simulation (M&amp;S) can be a good alternative to costly training. However, the use of existing M&amp;S for submarines has limitations. For instance, the commercial software and hardware need to be kept in a secure place. Depending on the location of the protected software, war fighters may travel far and take a considerable amount of time to get to these places. Long-distance travel also means they have a limited amount of time to train on the M&amp;S machines. Furthermore, many types of M&amp;S have only a one-channel display system, which reduces immersiveness. Another problem is that few heterogeneous simulators can be used as an integrated system. One solution to these problems involves the use of extensible 3D (X3D) graphics, a platform-independent and open standard graphic file format, which can be used with general purpose PCs. The immersiveness is increased by means of a multichannel display system and a motion chair. Finally, the individual components of a simulator can be integrated with the high level architecture and run time infrastructure (HLA/RTI). We demonstrate the proposed method through experiments with an underwater vehicle simulator.

Automatic dynamic modeling and simulation of underwater vehicles for virtual prototyping

AbstractThis article describes the theoretical foundations of a software intended for the virtual prototyping of underwater vehicles (UV). The software called Voyager, has a powerful graphics interface for generating the model and subsequently visualizing the results of the simulations. It is written in C++, using the OpenGL graphics engine.. © 2007 wiley Periodicals, Inc. Comput Appl Eng Educ 15: 340–346, 2007; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20139

AEROSIM for modelling, simulation and analysis of aerospace and underwater vehicles

This paper summarises the work done in the development of a flight simulation software package called AEROSIM by Rapid Data Ltd. The objective of this work is to use simulation and analysis facilities to reduce the development time and costs involved in aerospace vehicle modelling by providing a generic and extendible model combined with a user‐friendly graphical interface. Large parts of six degrees of freedom simulation models are common to all vehicles and AEROSIM exploits this by providing these parts ready written and developed. As a result the users have only to concern themselves with the specific details of their vehicle. AEROSIM generates a non‐linear model for aircraft, missile, airship, parafoil and underwater vehicle simulation.