Research on Hydrodynamics Model Test for Deepsea Open-Framed Remotely Operated Vehicle

This paper presents the features of newly designed hydrodynamics test for the scaled model of 4500 m deepsea open-framed remotely operated vehicle （ROV）, which is being researched and developed by Shanghai Jiao Tong University. Accurate hydrodynamics coefficients measurement and spatial modeling of ROV are significant for the maneuverability and control algorithm. The scaled model of ROV was constructed by 1：1.6. Hydrodynamics coefficients were measured through VPMM and LAHPMM towing test. And dynamics model was derived as a set of equations, describing nonlinear and coupled 5-DOF spatial motions. Rotation control motion was simulated to verify spatial model proposed. Research and application of hydrodynamics coefficients are expected to enable ROV to overcome uncertainty and disturbances of deepsea environment, and accomplish some more challengeable and practical missions.

Modeling and Testing of Hydrodynamic Damping Model for a Complex-shaped Remotely-operated Vehicle for Control

在这份报纸，塑造建筑群的遥远地操作的车辆(ROV ) 的数字建模并且模型测试被显示出。纸强调了在塑造建筑群的 ROV 上用计算液体抑制动态软件 ANSYS-CFX 的水动力学的系统的建模，不是的一个惯例通常适用。为在发展阶段期间测试的起始的设计和原型，用一个免费腐烂的实验的小规模的测试被用来验证从 ANSYS-CFX 获得的理论模型，模拟结果被显示与试验性的测试与一致。建议方法能决定抑制 ROV 的系数的水动力学。

基于自适应S面算法的小型ROV艏向和深度运动控制研究

带缆遥控水下机器人(ROV)系统艏向与深度运动具有强非线性和运行环境不确定性等特点。针对ROV的运动特点,构建运动控制模型并进行化简,通过构建自适应S面控制法对艏向与深度进行控制,并利用Lyapunov的稳定性判据证明该控制法的稳定性,通过仿真验证了该控制法具有良好的稳定性和控制品质。同时,与S面控制法相比,自适应S面控制具有更好的动态性能与静态性能,调节速度快、稳定性强,能够准确控制ROV运动。

基于RBF神经网络补偿的ROV运动控制算法

针对作业型遥控水下航行器(ROV)在模型参数不确定和外部环境干扰下的运动控制问题,提出了一种基于径向基函数(RBF)神经网络的自适应双环滑模控制策略。首先,对于ROV外环位置控制采用改进趋近律的积分滑模控制方法,对于ROV内环速度控制采用指数趋近律的积分滑模控制方法;其次,为进一步改善滑模控制的抖振问题,引入双曲正切函数作为滑模切换项;然后,利用RBF神经网络控制技术对ROV模型的不确定参数和外部扰动进行估计与补偿;最后,利用李雅普诺夫稳定性理论证明了整个闭环系统的稳定性,并对作业型ROV的运动控制进行了数值仿真。仿真结果验证了所设计的控制器可以实现ROV航行的精确控制,并能够有效抑制模型不确定参数和外部扰动对ROV运动的影响。

基于改进混合运动麻雀搜索算法的水电站ROV路径规划

水下遥控机器人(ROV)路径规划是水电站水下巡检作业的关键。针对电站水库下复杂环境及现有路径规划算法存在规划时间长、算法稳定性差、易陷入局部最优及生成路径不平滑等问题,提出一种基于改进混合运动麻雀搜索算法的水电站ROV路径规划方法。首先,引入佳点集改进麻雀种群初始化方法,提高了种群多样性;其次,提出混合运动策略优化麻雀群体位置更新方式,提高了算法收敛精度及稳定性;然后,结合工程实际问题,考虑水库下水流速度大、强磁场、障碍物以及投入成本等因素,建立了包含时间成本、路径威胁、水流扰动和偏置函数的多元目标函数;最后,采用三次B样条插值得到最优光滑路径。仿真结果表明,相较于其他路径规划算法,所提方法在计算精度、收敛速度和稳定性方面表现更好,适用于水电站水下巡检任务。

基于迁移学习的ROV水下建筑物缺陷识别方法

水下建筑物缺陷检测是保障电厂长期安全稳定运行的关键。为解决检测任务繁重危险,提高检测效率,降低人工检测成本,提出一种基于水下机器人(ROV)的水下建筑物缺陷识别方法。针对水下成像环境复杂、噪声大、检测流程冗长等问题,设计了一种基于迁移学习的图像识别模型。首先,通过图像数据处理算法,提高水下缺陷图像质量,并对图像进行二值化处理,突出缺陷特征;然后通过卷积核提取图像中的突出特征,引入注意力机制对特征重要程度进行计算分配,提高模型特征提取效率;最后在训练过程中引入迁移学习,解决实际缺陷数据不足的问题,提高模型训练效率。结果表明,设计的迁移学习图像识别模型在标准数据集和实测缺陷数据集上准确率达到90%~95%,且迭代次数在30代以内,能够精确高效识别水下建筑物缺陷特征。

OBLIQUE TOWING TEST AND MANEUVER SIMULATION AT LOW SPEED AND LARGE DRIFT ANGLE FOR DEEP SEA OPEN-FRAMED REMOTELY OPERATED VEHICLE

This article presents the newly designed oblique towing test in the horizontal plane for the scaled model of 4 500 m deep sea open-framed Remotely Operated Vehicle （ROV）,which is being researched and developed by Shanghai Jiao Tong University.Accurate hydrodynamics coefficients measurement is significant for the maneuverability and control system design.The scaled model of ROV was constructed by 1：1.6.Hydrodynamics tests of large drift angle were conducted through Large Amplitude Horizontal Planar Motion Mechanism （LAHPMM） under low speed.Multiple regression method is adopted to process the test data and obtain the related hydrodynamic coefficients.Simulations were designed for the horizontal plane motion of large drift angle to verify the coefficients calculated.And the results show that the data can satisfy with the design requirements of the ROV developed.

Automatic analysis of deep-water remotely operated vehicle footage for estimation of Norway lobster abundance

Underwater imaging is being used increasingly by marine biologists as a means to assess the abundance of marine resources and their biodiversity. Previously, we developed the first automatic approach for estimating the abundance of Norway lobsters and counting their burrows in video sequences captured using a monochrome camera mounted on trawling gear. In this paper, an alternative framework is proposed and tested using deep-water video sequences acquired via a remotely operated vehicle. The proposed framework consists of four modules:(1) preprocessing,(2) object detection and classification,(3) object-tracking, and(4) quantification. Encouraging results were obtained from available test videos for the automatic video-based abundance estimation in comparison with manual counts by human experts(ground truth). For the available test set, the proposed system achieved 100%precision and recall for lobster counting, and around 83% precision and recall for burrow detection.

基于改进YOLOv5s的桥墩缺陷检测ROV设计应用

针对桥墩附近乱流现象严重和桥墩表面光滑难以吸附的问题,采用浮游加抱臂爬行方式,利用复合控制技术设计了一款桥墩缺陷检测ROV。首先,ROV本体结构采用8矢量推进器布局方案,实现了机器人浮游状态全向运动,提高了ROV抗扰能力;其次,抱臂夹持机构采用绳传动方式,以机械简单联动为ROV爬行状态下的稳定检测提供了可靠平台;最后,采用基于注意力机制改进的YOLOv5s网络识别桥墩缺陷,通过引入ASPP、IAAM等结构,提升了缺陷检测的实时性与精度。真实水域试验结果表明,所设计的ROV具有很好的适用性和有效性,在复杂水域环境下取得了较好的桥墩缺陷检测应用效果,可代替潜水员完成桥墩缺陷采集工作。

Using Unmanned Underwater Vehicles as Research Platforms in Coastal Ocean Studies

The advantages of using unmanned underwater vehicles in coastal ocean studies are emphasized. Two types of representative vehicles, remotely operated vehicle (ROV) and autonomous underwater vehicle (AUV) from University of South Florida, are discussed. Two individual modular sensor packages designed and tested for these platforms and field measurement results are also presented. The bottom classification and albedo package, BCAP, provides fast and accurate estimates of bottom albedos, along with other parameters such as in-water remote sensing reflectance. The real-time ocean bottom optical topographer, ROBOT, reveals high-resolution 3-dimentional bottom topography for target identification. Field data and results from recent Coastal Benthic Optical Properties field campaign, 1999 and 2000, are presented. Advantages and limitations of these vehicles and applications of modular sensor packages are compared and discussed.

Design of motion control of dam safety inspection underwater vehicle

Plenty of dams in China are in danger while there are few effective methods for underwater dam inspections of hidden problems such as conduits,cracks and inanitions.The dam safety inspection remotely operated vehicle(DSIROV) is designed to solve these problems which can be equipped with many advanced sensors such as acoustical,optical and electrical sensors for underwater dam inspection.A least-square parameter estimation method is utilized to estimate the hydrodynamic coefficients of DSIROV,and a four degree-of-freedom(DOF) simulation system is constructed.The architecture of DSIROV's motion control system is introduced,which includes hardware and software structures.The hardware based on PC104 BUS,uses AMD ELAN520 as the controller's embedded CPU and all control modules work in VxWorks real-time operating system.Information flow of the motion system of DSIROV,automatic control of dam scanning and dead-reckoning algorithm for navigation are also discussed.The reliability of DSIROV's control system can be verified and the control system can fulfill the motion control mission because embankment checking can be demonstrated by the lake trials.

Remote Operation SW for USV: Part II. Simulation Development

For contingencies occurring in a complex marine environment, Unmanned Surface Vehicle (USV) has to recognize the situation and decide behaviors,?and?plan the following actions through the Integrated Mission Planning Process. Therefore, researches are actively being carried out about it. However, since it is difficult to test the actual USV with the mission planning process, it is necessary to develop a virtual experimental environment based on Modeling?&?Simulation (M&S). In this study, we developed an integrated simulation environment capable of simulating and analyzing the overall mission of USV. In Part?I, we modelled the USV Integrated Mission Planning Process and in Part?II, we developed an experimental framework and interface for loading them. In addition, we verified the suitability of this model through scenarios and defined the Mission of Effectiveness (MOE) concept for USV mission analysis.

Remote Operation SW for USV: Part I. Integrated Mission Planning System

The integrated Mission Planning System?(MPS) of Unmanned Surface Vehicle?(USV) refers to the process which can recognize, decide, plan situations and carry out missions, such as human beings, for all incidental or complex events occurring at sea. In the actual operating environment, it is necessary to develop a simulation software environment and analyze, verify it in advance so as to make an appropriate mission plan considering equipment, sensor, fuel, and other available resources. The existing USV mission planning process methodology has several limitations in the analysis of USV missions because the scenario to be tested is limited and autonomy of USV is not considered sufficiently. To overcome these problems, we constructed a process that considers various missions and is more autonomous, and an integrated environment in which to experiment. In this study, we designed a multi-agent based USV Integrated Mission Planning System and modeled each component. In addition, we constructed the USV remote operation S/W based on M&S that user can experiment with the modeled process and verified the usefulness of the developed system through simulations.

An approach to operational risk modeling and estimation of safety levels for deep water work class remotely operated vehicle-A case study with reference to ROSUB 6000

This paper presents a quantitative approach to operational risk modeling and estimation of safety integrity levels,required for the deep water electric work class remotely operated vehicle with reference to ROSUB6000 developed by the National Institute of Ocean Technology,India.ROSUB6000 is used for carrying out bathymetric surveys,gas hydrate surveys,poly-metallic nodule exploration,salvage operations,and meeting emergency response situations.The system is expected to be in operation for a period of 300 h per year,and has to be extremely safe and reliable.Methods and models for the quantitative assessment of operational safety and estimation of safety integrity levels for ROV are seldom available in the deep water intervention industry.The safety instrumented functions implemented in the ROV should be able to meet the SIL requirements of specific mission.This study indicates that the required safety factors are implemented into the design of the state-of-the-art ROV ROSUB 6000,considering IEC 61508/61511 recommendations on Health,Safety and Environment and it is found that the system is able to meet the required SIL for seven identified functions.This paper gives the design and safety engineers in the ROV industry,an overview of the numerical operational risk assessment methods and safety-centered ROV engineering.

推力受限的ROV预设性能精准跟踪控制

[目的]针对有缆水下机器人(ROV)推进器推力/力矩受限的现实情况,研究面向三维轨迹跟踪的预设性能精准控制问题,同时考虑系统不确定性、水下环境干扰等未知因素,提出基于有限时间扩张状态观测器和预设性能变换的精准跟踪控制方案,确保轨迹跟踪误差快速镇定。[方法]首先,针对推进器饱和约束,设计补偿系统消除输入饱和限制;其次,设计有限时间扩张状态观测器,对外界扰动和未知系统动态进行集总观测和补偿;进而,基于预设性能函数和误差转换函数,将受预设性能限制的跟踪误差转换成非受限的跟踪误差并构造积分滑动模态,采用快速幂次趋近律和边界层减缓执行器抖振;最后,采用Lyapunov理论证明所提出算法的整体稳定性。[结果]仿真结果验证了所设计控制方法的有效性和优越性。[结论]该控制方案可为解决集总扰动下推力受限的ROV轨迹跟踪预设性能精准控制问题提供一种新的解决方案。

基于ROV的TSS440探测系统在井场调查中的应用

该文描述在中国某海域井场海缆调查中,采用ROV搭载TSS440系统,通过设计测线,对井场内的疑似海缆进行调查,ROV搭载吹泥工具对发现的海缆进行除泥,以确认海缆及其路由的情况。研究结果表明,TSS440便于ROV搭载和安装,通过TSS440的调查结果以及除泥后海缆的确认,确定井场中海缆的存在和路由信息,调查结果可靠,为后期的钻井活动提供宝贵的参考信息。

ROV在沿海核电站取排水管廊检查中的应用

探讨小型无人遥控潜水器(Remotely Operated Vehicle,ROV)在沿海核电站排水管廊检查中的应用及关键技术。首先,阐述ROV在海洋工程领域的研究和应用现状,分析其在海底工程中的应用优势。其次,分析ROV在沿海核电站取排水管廊检查中应用的可行性、可靠性、优越性和作业流程,进一步探讨ROV搭载各种功能的工具、设备、仪表解决不同工况需求。最后,研究和总结已有ROV在秦山核电站排水管廊检查中的应用案例,验证该技术在核电领域的可行性和有效性。

Bi-criteria Optimal Fault-Tolerable Control for SY-II Remote Operated Vehicle

This paper proposed a bi-criteria weighting approach for fault tolerant control(FTC)of SY-II remote operated vehicle(ROV).This approach integrates the minimum kinetic energy(2-norm optimal)approach with the infinity-norm approach through a weighting coefcient,on the basis of SY-II ROV force allocation model.For the realization of fault tolerable control,this approach converts a quadratic programming problem into primaldual neural network.From the motion control simulations and experiments,bi-criteria optimization approach outperforms minimum kinetic energy optimization in FTC,SY-II ROV can realize 2-degree of freedom(DOF)horizontal fault tolerant control with one main thruster and any of horizontal ones.Therefore,this scheme is proved to be of superiority and computational efciency,both the reliability and safety for ROV have been improved.

“海马”号ROV在天然气水合物勘查中的应用

天然气水合物作为未来的战略性新型能源矿产,在我国南海成功实现了试开采,对推动新的清洁能源生产具有重要而深远的影响。文中介绍了由我国自主研制的首套大深度作业型ROV系统("海马"号)的组成和结构特点,详细阐述了充分利用"海马"号ROV的灵活、全面、立体的作业性能,有针对性的配置了三视角高清摄像、机械手专用工具、海水温度、甲烷含量测量、声呐、定位信标等设备工具,进行了搜索、详查、观测、触探、取样、实验等水合物勘查作业,发现了海底"冷泉"活动以及与天然气水合物赋存相关的微地貌特征等,"海马"号的应用极大地推进了我国天然气水合物的研究和开发进展,未来将在天然气水合物勘查和科学研究中发挥重要作用。

Detecting large-scale underwater cracks based on remote operated vehicle and graph convolutional neural network

It is of great significance to quickly detect underwater cracks as they can seriously threaten the safety of underwater structures.Research to date has mainly focused on the detection of above-water-level cracks and hasn’t considered the large scale cracks.In this paper,a large-scale underwater crack examination method is proposed based on image stitching and segmentation.In addition,a purpose of this paper is to design a new convolution method to segment underwater images.An improved As-Projective-As-Possible(APAP)algorithm was designed to extract and stitch keyframes from videos.The graph convolutional neural network(GCN)was used to segment the stitched image.The GCN’s m-IOU is 24.02%higher than Fully convolutional networks(FCN),proving that GCN has great potential of application in image segmentation and underwater image processing.The result shows that the improved APAP algorithm and GCN can adapt to complex underwater environments and perform well in different study areas.