共查询到19条相似文献，搜索用时 125 毫秒
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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
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基于模糊神经网络理论对水下拖曳体进行深度轨迹控制 总被引：2，自引：0，他引：2
以华南理工大学开发的自主稳定可控制水下拖曳体为研究对象,首先通过水下拖曳体在拖曳水池样机中的试验取得试验数据后作为训练样本,采用LM BP算法,建立基于神经网络理论构建的可控制水下拖曳体轨迹与姿态水动力的数值模型。在此基础上设计了一个控制系统,它主要由两部分组成:基于遗传算法的神经网络辨识器和基于模拟退火改进的遗传算法的模糊神经网络控制器。以满足预先设定的拖曳体水下监测轨迹要求为控制依据,由控制系统确定为达到所要求的运动轨迹而应采用的迫沉水翼转角,以此作为输入参数,通过LM BP神经网络模型的模拟计算预报在这一操纵动作控制下的拖曳体所表现的轨迹与姿态特征。数值模拟计算结果表明:该系统的设计达到了所要求的目的;借助这一系统,可以有效地实现对拖曳体的深度轨迹控制。 相似文献
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水下拖曳航行器是被广泛应用的水下监测平台。为掌握水下拖曳航行器的水动力及其拖揽姿态，文章通过CFD仿真分析计算其零攻角下的阻力系数，并通过多刚体-球铰模型建立其运动数学模型，分析不同航速下拖曳系统的总拉力、拖缆长度和航行器位置等的参数变化。研究结果表明：随着船舶航速的变化，拖曳系统各项参数变化的差别很大；在200 m深度时，6 kn航速相比4 kn航速的总拉力增加73%，而所需的拖缆长度仅增加1%。该数学模型可对不同航速下的水下拖曳系统的总拉力和拖缆姿态等做出预测，为拖曳系统设计提供技术支撑。 相似文献
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《海洋技术学报》2018,(6)
为研究极地浮冰的漂移对冰基拖曳式浮标水下拖曳标体运动的影响,设计了一种恒速牵引装置,模拟极地浮标的定向移动,用于定量研究拖曳标体在不同漂移速度下的的沉浮规律,为标体的设计提供数据支持。该装置用可编程控制器PLC作为主控制器,以步进电机为执行器,编码器测算牵引速度,通过PID算法控制牵引速度保持恒定。用LabVIEW设计了上位机控制界面,能够对PLC进行控制和状态监视,并可显示存储牵引速度值。实验结果表明该装置可在600 m的牵引行程内,牵引速度误差小于2%,符合定量模拟浮冰漂移速度的控制要求。在浮标静水拖曳试验中使用该装置模拟水面标体随风低速漂移,可以定量给出水下拖曳体的最大下潜深度,对极地拖曳式浮标系统的开发和布放前的检验具有重要意义。 相似文献
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分析大深度潜航器水下空间运动特点，建立描述其空间运动的数学模型，并以数学模型为基础利用 MATLAB\Simulink 软件完成潜航器空间运动仿真模型的开发。在搭建的仿真模型基础上，通过数学仿真手段分析了潜航器在螺旋下潜、抛载过渡、定角爬升、稳定至水面航行状态下的水下运动全过程，给出了具有弧形翼板的潜航器外形设计方案的运动能力仿真评估，为后续潜航器运动能力优化设计提供仿真依据。 相似文献
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A hydrodynamic model of a two-part underwater manoeuvrable towed system is proposed in which a depressor is equipped with active horizontal and vertical control surfaces, and a towed vehicle is attached to the lower end of a primary cable. In such a system the towed vehicle can be manoeuvred in both vertical and horizontal planes when it is towed at a certain velocity and the coupling effect of excitations at the upper end of the primary cable and disturbances of control manipulations to the towed vehicle can be reduced. In the model the hydrodynamic behavior of an underwater vehicle is described by the six-degrees-of-freedom equations of motion for submarine simulations. The added masses of an underwater vehicle are obtained from the three-dimensional potential theory. The control surface forces of the vehicle are determined by the wing theory. The results indicate that with relative simple control measures a two-part underwater manoeuvrable towed system enables the towed vehicle to travel in a wide range with a stable attitude. The method in this model gives an effective numerical approach for determining hydrodynamic characteristics of an underwater vehicle especially when little or no experimental data are available or when costs prohibit doing experiments for determining these data. 相似文献
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Low-frequency electromagnetic methods are used in geophysical exploration to detect the magnetic field distortion between a transmitter and receiver produced by locally conductive bodies. Both ground and airborne systems are in current use. It is possible to similarly conduct underwater geophysical exploration by using an underwater towed source of electromagnetic radiation and a receiving magnetic or electric field detector. The receiver can be towed on an auxiliary cable, mounted on a boom on the towing platform, or land based. An underwater towed electromagnetic source suitable for ocean-bottom exploration has been constructed, and its underwater propagation characteristics at low frequency have been studied. This underwater calibrated source (UCS) is 4 m long, weighs 383 kg in air, and can produce vertical and horizontal magnetic dipoles and a horizontal electric dipole. Powered by a current-feedback-controlled, high-power, modified sonar amplifier, the UCS can produce 9710 ampereturn.m2 of magnetic dipole or 200 A.m of electric dipole at 50 A at frequencies up to 200 Hz without significant attenuation from coil inductance. This paper concentrates on the mechanical, hydrodynamic, and magnetic design details of the UCS and the electrical system, consisting of the high-current drive power system and the shipboard monitoring system for attitude and depth detectors. 相似文献
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This paper addresses the problem of simultaneous depth tracking and attitude control of an underwater towed vehicle. The system proposed uses a two-stage towing arrangement that includes a long primary cable, a gravitic depressor, and a secondary cable. The towfish motion induced by wave driven disturbances in both the vertical and horizontal planes is described using an empirical model of the depressor motion and a spring-damper model of the secondary cable. A nonlinear, Lyapunov-based, adaptive output feedback control law is designed and shown to regulate pitch, yaw, and depth tracking errors to zero. The controller is designed to operate in the presence of plant parameter uncertainty. When subjected to bounded external disturbances, the tracking errors converge to a neighbourhood of the origin that can be made arbitrarily small. In the implementation proposed, a nonlinear observer is used to estimate the linear velocities used by the controller thus dispensing with the need for costly sensor suites. The results obtained with computer simulations show that the controlled system exhibits good performance about different operating conditions when subjected to sea-wave driven disturbances and in the presence of sensor noise. The system holds promise for application in oceanographic missions that require depth tracking or bottom-following combined with precise vehicle attitude control. 相似文献
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主动式声纳列阵拖曳系统姿态数值计算 总被引：2，自引：1，他引：2
主动式声纳列阵拖曳系统是用于探测潜艇的新型声纳系统，为了准确探测潜艇的位置，必须首先预报声纳列阵的瓷态，本文通过对其三维力学模型的分析，得到该系统的运动微分方程，其中缆索的力学方程是基于Ablow和Milinazzo的模型，而对于拖体则运用六自由度空间运动方程模拟，结合边界条件，用有限差分法求解，通过对拖船的不同运动状态如匀速，变速和回转的计算，证明本文的方法对于预报声纳列阵的姿态是有效的。 相似文献
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多波束测深技术是目前水下地形测量的主要技术手段,测量平台的瞬时姿态及方位是影响多波束测深系统最终成果准确度的重要因素。GNSS方位辅助惯性导航系统,作为目前应用较为广泛的方位、姿态、及位置综合测量系统,不仅能够提供高精度位置信息,同时也能提供测量平台的瞬时姿态及方位数据,而且因为具有GNSS方位辅助测量,使得最终方位测量结果比传统方位测量精度大大提高,这对于多波束最终测量成果精度提高具有重要意义。文中从GNSS方位辅助惯性导航系统原理及技术优势出发,结合Trimble RTX后处理技术,从姿态测量、方位测量及辅助高程测量方面分析了在多波束水下地形测量中的应用,并以实际测量成果来展现其在水下地形精密测量技术方面的优势,结果显示,定位精度可以达到优于2 cm级别,方位精度可以优于0.01°(依赖于双GNSS天线之间的基线长度),该技术对水下地形测量准确度提升作用显著。 相似文献
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A novel self-contained navigation system has been devised for underwater vehicles operating in and around offshore installations. This system matches data from a sector-scanning sonar device to a computer model of the installation. The paper begins by highlighting the existing approaches to subsea navigation before outlining the main features of the proposed system. It then concentrates on a key component of this system which is a method for calculating the position and heading of an underwater vehicle navigating in the vincinity of tubular steel structures. An iterative solution method is presented which incorporates six degree of freedom vehicle motions and this is verified in a series of laboratory experiments with various arrangements of structural members and using a commercial sonar device. The key features, applications and performance of this method are discussed. The main conclusion is that the proposed method for calculating the position and heading of an underwater vehicle contributes towards achieving an accurate and reliable subsea navigation capability. 相似文献
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针对海洋测量水下拖曳设备位置确定问题,综合考虑拖缆受力、海流影响以及水下拖体的运动性质,建立了水下拖曳设备的位置计算模型,并仿真计算分析了测量船在不同航行状态下拖曳设备位置确定的规律,探讨了不同海流效应对拖曳设备位置确定的影响。仿真计算结果表明,在海洋动态环境作用下,拖缆各方向的偏移明显呈曲线形状,非简单几何运算所确定。测船各方向的运动均可对水下拖体的位置在相应方向产生一定影响,而水下拖体位置的变化量小于测船拖点位置的变化量。海流对水下拖曳设备定位可造成数米的偏差,需进行相应改正。建议可考虑采取船载式ADCP实时测流辅助水下拖曳设备定位的工作模式。 相似文献
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A three-dimensional model of a two-part underwater towed system is studied. In the model, the governing equations of cables are established based on the Ablow and Schechter method. The boundary conditions for the two-part underwater towed system are derived. The six-degrees-of-freedom equations of motion for submarine simulations are adopted to predict the hydrodynamic performance of a towed vehicle. The established governing equations for the system are then solved using a central finite difference method. In this paper several algorithms are used to solve this special form of finite difference equations. The results in this paper indicate that the two-part underwater towed system improves the dynamic behavior of the towed vehicle and is an easy way to decouple the towing ship motion from the towed vehicle. Because the model uses an implicit time integration, it is stable for large time steps and is an effective algorithm for simulation of a large-scale underwater towed system. 相似文献
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受大深度水体的影响,传统的海面拖曳式多道地震技术在进行深水地层探测时,目标地层深度处的菲涅耳半径非常大,水平分辨率低,难以满足海域天然气水合物高精度探测需求。针对海面拖曳式地震探测技术存在的上述问题,设计了一套可以在2000 m水深近海底作业的地震探测系统。应用耐压透声发射阵技术,克服了20 MPa外压环境和瞬时内压冲击对等离子体震源子波幅频特性的不利影响,研制的深拖等离子体震源的声源级达到214 dB,主频低于1000 Hz;水下控制中心采用集成SoC片上系统设计,可以对震源进行定距激发控制,进行近海底多道地震数据的连续采集。系统在2019年深海试验拖曳最大深度达2025 m,测试剖面数据显示最大地层穿透深度达380 m,纵向分辨率<2 m,横向分辨率<10 m,为深水海域沉积地层的深拖高分辨率地震探测提供了技术支撑。 相似文献