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1.
Robust control based on feedback linearization for roll stabilizing of autonomous underwater vehicle under wave disturbances 总被引：1，自引：0，他引：1
In the case of Autonomous Underwater Vehicle(AUV) navigating with low speed near water surface,a new method for design of roll motion controller is proposed in order to restrain wave disturbance effectively and improve roll stabilizing performance.Robust control is applied,which is based on uncertain nonlinear horizontal motion model of AUV and the principle of zero speed fin stabilizer.Feedback linearization approach is used to transform the complex nonlinear system into a comparatively simple linear system.For parameter uncertainty of motion model,the controller is designed with mixed-sensitivity method based on H-infinity robust control theory.Simulation results show better robustness improved by this control method for roll stabilizing of AUV navigating near water surface. 相似文献
2.
Huang Guoliang Liu Tianwei Yan Naichang
Associate Professor Shanghai Jiao Tong University Shanghai
Engineer Shanghai Jiao Tong University Shanghai .
Professor Shanghai Jiao Tong University Shanghai 《中国海洋工程》1997,(4)
In this paper,the maneuvering characteristics of a low speed submersible are investigated.First,the captive model tests are carried out to obtain the hydrodynamic forces acting on the submersibleusing a Planar Motion Mechanism(PMM).For the hydrodynamic forces within a wide range of attack an-gles,the hydrodynamic coefficients which are usually used in the conventional maneuvering motion arequite difficult to be applied.In this case,a Fourier series is adopted to represent the hydrodynamic forcesand it fits the experimental data well.Then,based on the experimental results the simulation calculationsare made to predict some of the maneuvering performance of the low speed submersible. 相似文献
3.
扁平潜器微速操纵性研究 总被引：1，自引：0，他引：1
针对扁平潜器的特点建立了其微速操纵性运动方程,提出了忽略攻角、漂角与旋转角速度耦合影响的水动力模型,由拖曳水池模型试验确定了攻角、漂角水动力,近似估算了旋转水动力.在主辅推进器的PD控制下,数值仿真计算了水平面航向保持与改变、垂直面潜浮的微速运动控制. 相似文献
4.
内尔斯海峡位于加拿大埃尔斯米尔岛与格陵兰岛之间,是北极海冰输出的重要通道之一,这些海冰融化后带来的表层淡水对巴芬湾、拉布拉多海的深层水形成具有重要影响。但由于该海峡较为狭窄,缺乏对此区域海冰运动情况的精细研究。本研究利用每日的哨兵1号影像提取了2016年9月至2017年8月的内尔斯海峡北部区域海冰运动信息,展示了海峡中浮冰的运动过程,并结合风速、海流速度等数据分析浮冰运动特征及影响因素。结果表明风和海流二者共同主导了海冰的运动过程,相关系数分别达到了0.767和0.709,由风速、海流速度、海冰密集度3个自变量与浮冰速度建立的多元线性回归模型复决定系数也达到了0.727。进一步分析发现,风和海流在速度相对稳定时对浮冰速度的影响都会减小。本研究关于风和海流等要素对海冰运动过程影响的研究结果,可以为海洋–大气动力学模型的研究提供参考。 相似文献
5.
In this paper, the hydrodynamic characteristic of a synthetic jet steered underwater vehicle is studied. The steering motion studied is the lateral motion and the yaw motion. The lateral motion is induced through the in-phase work of this two actuators and the yaw motion is realized through the out-of-phase work. The vehicle studied is REMUS AUV with synthetic jet actuator mounted inside. The hydrodynamic characteristic of the vehicle under different cruising speed is studied. The driving parameters of the SJ actuator keep invariant in different cases. When the two actuators work in phase, the average steering force is smaller than the thrust of the isolated actuator and keeps nearly invariant under different cruising speed. When the two actuators work out of phase, the average steering moment also keeps invariant with cruising speed. The mathematical model of the additional drag of the vehicle, the thrust of the actuator, the steering force as well as the steering moment is given. The velocity distribution is also given to assistant the analysis in this paper. From the analysis given it can be known the steering method based on SJ is realized through position control other than velocity control. 相似文献
6.
Mohammad Saeed SEIF Ebrahim JAHANBAKHSH Roozbeh PANAHI Mohammad Hossein KARIMI 《海洋工程》2009,(3):517-528
High speed planing hulls have complex hydrodynamic behaviors. The trim angle and drafts are very sensitive to speed and location of the center of gravity. Therefore, motion simulation for such vessels needs a strong coupling between rigid body motions and hydrodynamic analysis. In addition, free surface should be predicted with good accuracy for each time step. In this paper, velocity and pressure fields are coupled by use of the fractional step method. On the basis of integration of the two-phase viscous flow induced stresses over the hull, acting loads (forces and moments) are calculated. With the strategy of boundary-fitted body-attached mesh and calculation of 6-DoF motions in each time step, time history of ship motions including displacements, speeds and accelerations are evaluated. For the demonstration of the software capabilities, circular cylinder slamming is simulated as a simple type of water slamming. Then, a high-speed planing catamaran is investigated in the case of steady forward motion. All of the results are in good concordance with experimental data. The present method can be widely implemented in design as well as in performance prediction of high-speed vessels. 相似文献
7.
针对船舶气象仪的综合检查过程中检测周期长、人工排查效率低以及传统的自动气象站传感器信号模拟器的模拟精度低,没有相关运动补偿算法导致此类系统不适应海洋船舶应用环境的问题,对气象要素传感器的高精度信号采样电路、信号输出、软件滤波和运动补偿等方面进行了研究。通过分析传感器和船舶气象仪的原理,设计了各个气象参数的采样电路、信号模拟电路、触摸屏、GPS和电子罗盘采样与模拟电路,并在近海测试过程中进行了运动补偿模型测试,并基于STM32微控制器进行了该仪器的系统检测实验。研究测试结果表明：该系统具有低功耗、高可靠性、高精度的特点,能应用于海上环境,同时具有对船舶实时定位、气象要素实时模拟和采集、运动补偿多项功能。并且本系统精度在运动补偿后,系统测量方差为0.019 3 m/s,精度提高至接近真实值,均符合《海洋调查规范第3部分：海洋气象观测》的标准。 相似文献
8.
A hybrid underwater glider Petrel-II has been developed and field tested. It is equipped with an active buoyancy unit and a compact propeller unit. Its working modes have been expanded to buoyancy driven gliding and propeller driven level-flight, which can make the glider work in strong currents, as well as many other complicated ocean environments. Its maximal gliding speed reaches 1 knot and the propelling speed is up to 3 knots. In this paper, a 3D dynamic model of Petrel-II is derived using linear momentum and angular momentum equations. According to the dynamic model, the spiral motion in the underwater space is simulated for the gliding mode. Similarly the cycle motion on water surface and the depth-keeping motion underwater are simulated for the level-flight mode. These simulations are important to the performance analysis and parameter optimization for the Petrel-II underwater glider. The simulation results show a good agreement with field trials. 相似文献
9.
《中国海洋工程》2017,(1)
A hybrid underwater glider Petrel-II has been developed and field tested. It is equipped with an active buoyancy unit and a compact propeller unit. Its working modes have been expanded to buoyancy driven gliding and propeller driven level-flight, which can make the glider work in strong currents, as well as many other complicated ocean environments. Its maximal gliding speed reaches 1 knot and the propelling speed is up to 3 knots. In this paper, a 3D dynamic model of Petrel-II is derived using linear momentum and angular momentum equations. According to the dynamic model, the spiral motion in the underwater space is simulated for the gliding mode. Similarly the cycle motion on water surface and the depth-keeping motion underwater are simulated for the level-flight mode. These simulations are important to the performance analysis and parameter optimization for the Petrel-II underwater glider.The simulation results show a good agreement with field trials. 相似文献
10.
利用基于三维势流理论的Wasim软件,系统研究了在不同海况下大型豪华邮轮的耐波性能及作用在救生艇上的砰击载荷。首先计算豪华邮轮在规则波和不规则波中的运动响应,分析航速、浪向和海况对豪华邮轮运动响应的影响规律,然后计算救生艇在不同海况下砰击载荷的变化规律,根据变化规律评估救生艇在实际航行中的安全性。结果表明：豪华邮轮运动响应幅值随着航速和海况的增大整体呈增大趋势,规则波中横摇运动响应幅值在浪向90°时最大;当豪华邮轮处于4级和6级海况时救生艇不发生砰击;当豪华邮轮处于8级海况且航速大于10.29 m/s时救生艇发生砰击,为保证救生艇的安全,邮轮应避免在浪向120°和浪向150°下航行,此时建议邮轮以低于12.35 m/s的航速迎浪180°航行。 相似文献
11.
Water motion is a very important environment surrounding marine organisms. It is, however, difficult to measure currents with a propeller type of current meters in seagrass or seaweed beds in shallow waters. Therefore, we elaborate the measuring method of time-averaged intensity of water motion with plaster balls invented by Muus (1968) to set them at several depths at short vertical intervals in shallow waters. Theoretical examination is also made on the relation between speed of steady flow and dissolution rate of plaster balls by experiments in a circuit tank. These experiments revealed that the temporal rate of decrease in the 1/2 power of wet weight of plaster balls excluding a rod supporting the plaster ball was proportional to the speed of steady flow in the tank. On the basis of this relation, we propose the method for estimating the time-averaged intensity of water motion by converting the loss of wet weight of plaster ball to the speed of steady flow bringing equivalent loss. Since this method is simple and convenient, it can be applied to obtaining environmental indices of water motion not only in seagrass or seaweed forests, but also in fishing grounds culturingporphyra, yellow tail (Seriola quinqueradiata) or oysters. 相似文献
12.
针对水产养殖中的精准投喂问题,以大西洋鲑(Salmo salar)为研究对象,提出一种基于鱼体运动特征和图像纹理特征的鱼群摄食活动强度量化方法,进行鱼类摄食行为识别研究。利用自适应背景差分及光流法得到运动鱼体的速度、转角,并通过信息熵统计速度和转角的分布,之后通过灰度共生矩阵提取能量、熵、对比度、相关性和逆差距5个图像纹理特征值。最后,结合鱼体运动特征及图像纹理特征,对鱼类摄食行为进行识别和检测。实验结果表明,该方法的识别准确率达到了94.17%,相较于单一特征检测本研究的检测精度更高。 相似文献
13.
In this study, a dynamic modeling method for foil-like underwater vehicles is introduced and experimentally verified in different sea tests of the Hadal ARV. The dumping force of a foil-like underwater vehicle is sensitive to swing motion. Some foil-like underwater vehicles swing periodically when performing a free-fall dive task in experiments. Models using conventional modeling methods yield solutions with asymptotic stability, which cannot simulate the self-sustained swing motion. By improving the ridge regression optimization algorithm, a grey-box modeling method based on 378 viscous drag coefficients using the Taylor series expansion is proposed in this study. The method is optimized for over-fitting and convergence problems caused by large parameter matrices. Instead of the PMM test data, the unsteady computational fluid dynamics calculation results are used in modeling. The obtained model can better simulate the swing motion of the underwater vehicle. Simulation and experimental results show a good consistency in free-fall tests during sea trials, as well as a prediction of the dive speed in the swing state. 相似文献
14.
Massimo Caccia 《Oceanic Engineering, IEEE Journal of》2006,31(3):711-727
A laser-triangulation optical-correlation sensor for estimating the motion of underwater vehicles at low speed in the proximity of the seabed is described. Experimental results, obtained by processing image sequences acquired by the instrument mounted below the Romeo remotely operated vehicle (ROV) in operating conditions, are presented 相似文献
15.
Mohammad Saeed SEIF Ebrahim JAHANBAKHSH Roozbeh PANAHI Mohammad Hossein KARIMI 《中国海洋工程》2009,23(3):517-528
High speed planing hulls have complex hydrodynamic behaviors. The trim angle and drafts are very sensitive to speed and location of the center of gravity. Therefore, motion simulation for such vessels needs a strong coupling between rigid body motions and hydrodynamic analysis. In addition, free surface should be predicted with good accuracy for each time step. In this paper, velocity and pressure fields are coupled by use of the fractional step method. On the basis of integration of the two-phase viscous f... 相似文献
16.
中尺度涡旋的运动整体可分为两部分：平移及转动。平移指涡旋在整个生命周期内的水平移动，而转动除了包括内转 （海表地转流引起的涡旋自身水体转动） 外，还包括形转 （涡旋实际边界最佳拟合椭圆的转动）。本文基于 1993—2018 年共计 26 年间的卫星高度计涡旋识别与追踪数据，首次对南海中尺度涡旋的完整运动形式，即形转、内转、平移展开了系统的研究。其中，对内转及平移的分析，可通过涡旋的识别追踪数据集直接进行；为研究涡旋形转，提出了一种基于涡旋识别追踪数据自动提取涡旋形转信息的算法，以此得到涡旋形转方向、每天形转的角度以及形转圈数等信息，获得涡旋形转数据集。通过对涡旋识别追踪数据以及形转数据集的统计分析发现：南海涡旋的平移方向多为西向，且其速率呈偏态分布，主要以南海南部偏高。同样，涡旋的内转速率也呈偏态分布，高速率内转的涡旋主要分布在吕宋海峡附近。涡旋的形转主要以南海南部速率偏高，且与涡旋的寿命及长轴有一定的关系，倾向于随着涡旋寿命的增长、涡旋长轴的增大而变慢。同时南海涡旋的这三种不同运动形式之间也存在一定的相关性。 相似文献
17.
Compared with bottom-fixed wind turbines,the supporting platform of a floating offshore wind turbine has a larger range of motion,so the gyroscopic effects of the system will be more obvious.In this paper,the mathematical analytic expression of the gyroscopic moment of a floating offshore wind turbine is derived firstly.Then,FAST software is utilized to perform a numerical analysis on the model of a spar-type horizontal axis floating offshore wind turbine,OC3-Hywind,so as to verify the correctness of the theoretical analytical formula and take an investigation on the characteristics of gyroscopic effect.It is found that the gyroscopic moment of the horizontal axis floating offshore wind turbine is essentially caused by the vector change of the rotating rotor,which may be due to the pitch or yaw motion of the floating platform or the yawing motion of the nacelle.When the rotor is rotating,the pitch motion of the platform mainly excites the gyroscopic moment in the rotor’s yaw direction,and the yaw motion of the platform largely excites the rotor’s gyroscopic moment in pitch direction,accordingly.The results show that the gyroscopic moment of the FOWT is roughly linearly related to the rotor’s inertia,the rotor speed,and the angular velocity of the platform motion. 相似文献
18.
In this paper, a wide variety of computed motion results is presented for three existing fishing vessels. In order to do that, time domain computations of 3D ship motions are performed with a time domain Green's function. The computational method adopted is based on a previously developed one, whose numerical scheme here is subjected to modifications that increase its robustness and overall efficiency, so that it can be applied to calculate the motions of fishing vessels. The results are then compared with simulations using WAMIT for the zero speed case, and a strip theory method is used to determine the effect of forward speed. Results are presented for head seas, quartering head waves and following waves with three distinct Froude numbers. 相似文献
19.
为了改善被测目标运动要素计算精度,提出了采用 PSO-BP 神经网络算法作为运动要素解算的方程。 该算法将粒子群算法作为 BP 神经网络的学习算法,提高 BP 网络的全局收敛性和收敛速度,将观测到的运动目标参数作为 PSO-BP 神经网络的输入,并将运动目标的方位作为主要输出量,将运动目标的方位值与误差期望值进行比较并作为 PSO 的输入修改 BP 网络权值,进而得到高精度 BP 神经网络。 对该算法进行仿真计算,结果表明:基于该算法的运动目标运动要素解算,尤其是运动方位的解算器精度可以达到 0. 128°,提高了运动要素解算的精度和速度。 相似文献
20.
海底矿石在软管中的水力输送是深海采矿的重要过程。采用计算流体动力学—离散元耦合的计算方法（CFD-DEM）,对矿石颗粒在软管中的输送进行数值模拟,重点关注矿石颗粒的运动、分布规律以及管壁受到的颗粒作用力,分析输送速度和输送浓度（入射颗粒的体积分数）对输送过程的影响规律,探索管道中易发生堵塞、易受颗粒磨损的区域。结果表明,软管中颗粒的动力学特性与管道倾角、输送速度和输送浓度有关。颗粒主要沿管道截面底部推移,倾角较大的上升段出现处于悬移状态的颗粒;管道横截面内颗粒运动速度从上至下递减,截面中心处颗粒的速度接近输送速度。输送过程中颗粒的局部浓度（该区域颗粒与固液两相流的体积比）始终大于输送浓度,局部平均速度始终小于输送速度。上升段颗粒体积分数大于下降段,颗粒速度小于下降段。管道拱顶和谷底位置管壁所受颗粒作用力最明显,管壁最可能受颗粒磨损。 相似文献