【作者】 刘超；

【导师】 熊木地；

【作者基本信息】 大连海事大学 ， 电子科学与技术， 2018， 硕士

【摘要】 随着近些年来国家的大力支持,内河水域经济发展需求的不断攀升,船舶货运量呈现出猛增趋势。但越来越重的船舶载货,使得船舶吃水深度激增,如果超吃水现象严重,则会威胁航道安全。为解决这些问题,需要对通航船舶进行吃水检测,当检测出超吃水违章船舶时,能够及时制止,从而避免事故的发生,有效地提高通航效率。目前国内外吃水检测方法均存在不小弊端,例如无法离船检测、准确性差等。为此,本文提出多频率超声波阵列侧扫式吃水检测系统,首先分析了水中超声波的多途效应以及衍射效应原理,根据这些原理完成了短时分时控制方法以及幅值细分技术的设计;其次对超声波换能器的特性展开了研究,为后续的超声波换能器选取提供了依据。根据多频率超声波阵列侧扫式吃水检测系统的要求,本文设计了 DSP多频率数据采集模块,实现不同频率超声波的发射与接收,利用频谱分析技术解析出对应每一路频率的超声波信号电压幅值,消除了通道间干扰,有效地提高了检测效率。设计了 ARM数据融合模块,与DSP多频率数据采集模块构成双核的实时采集结构,完成了超声波数据与水位计数据的提取融合、噪声处理等功能,并将数据通过光纤进行远程传输给上位机系统。研制的上位机软件系统采用中值滤波的方法解决了随机噪声的问题,采用换能器数据特性标准化方法解决因各种因素导致超声波换能器参数差异的问题,同时使用幅值细分技术提高了系统的检测精度。经过在大连海事大学校打捞馆的实验和三峡升船机现场的投入运行证明,本文开发的侧扫式吃水检测系统能够满足工程实际要求,技术方案可行。该系统经过中国计量科学院的计量认证,当航道宽度为30m时,测量精度达2.0cm;当航道宽度为50m时,测量精度达2.8cm。更多还原

【Abstract】 With the strong support from the state in recent years and the increasing demand for the economic development in inland waterways,the volume of shipments in ships shows a sharp increase.However,more and more ships carry cargo,making the surge in the depth of draft of the ship.If the draft is serious,it will threaten waterway safety.In order to solve these problems,it is necessary to conduct draft detection on navigable ships.When it is detected that the vessel in violation of regulations is over-draft,stop them in time to avoid accidents.So,it will effectively improve navigation efficiency.At present,there are some drawbacks in the draft test at home and abroad,such as the inability to disembark from the ship and poor accuracy.Therefore,this paper presents a multi-frequency ultrasonic array side sweep draft detection system.First of all,this paper analyzes the multipath effect and the principle of diffraction effect of ultrasonic waves in water.According to these principles,the short time-sharing control method and the design of amplitude subdivision technology are completed.Then,the characteristics of the ultrasonic transducer are studied,which provide the basis for the subsequent selection of the ultrasonic transducer.According to the requirements of the multi-frequency ultrasonic array side sweep draft detection system,this paper designs DSP multi-frequency data acquisition module to send and receive ultrasonic waves of different frequencies and analyzes the amplitude of the ultrasonic signal corresponding to each frequency of the spectrum by using spectrum analysis technique,and inter-channel interference is eliminated.The ARM data fusion module is designed and the dual-core real-time acquisition structure with DSP multi-frequency data acquisition module is completed.The functions of extraction and fusion of ultrasonic data and water level meter data,noise processing and so on are completed,and the data are transmitted to the host computer system.The developed PC software system uses the median filter method to solve the existing random noise problem.The transducer data characteristic standardization method is adopted to solve the problem of different parameters of the ultrasonic transducer caused by different factors,and the amplitude subdivision technique is used to improve the detection accuracy of the system.After the experiment at Dalian Maritime University Fishing Museum and the commissioning of the Three Gorges Ship Lift,it is proved that the side-sweep draft detection system developed in this paper can meet the actual engineering requirements and the technical scheme is feasible.The system has been accredited by the Chinese Academy of Metrology.When the width of the waterway is 30m,the measurement accuracy reaches 2.0cm.When the width of the waterway is 50m,the measurement accuracy reaches 2.8cm.更多还原