Research On Ship Draft Detection System Based On Underwater Moving Ultrasonic Ranging

With the rapid development of domestic economy,freight demand is increasing,inland shipping industry with its cost advantages,plays an important role in the economic and social development.With the continuous improvement of the freight demand along the Yangtze River,the manufacture of inland river ships is becoming more and more large,and the ship's draft value increases continuously.In the shallow reaches of the Yangtze River in dry season,the ship with large draft value is prone to stranded accidents,which not only causes safety problems of the ship itself,but also threatens other ships safety,affects the navigation efficiency.The key to solve the problem is to prevent the ship from over draft navigation,so it is very important to test the draft of the ship.In view of the disadvantages of the traditional manual monitoring,automatic ship detection methods are put forward,which do not affect the normal navigation and increase the detection efficiency.The ship detection technology trends initiative,independent and real-time based on the underwater environment and the complex,ultrasonic wave has strong penetrating power in water,energy attenuation is small,high detection precision,sonar measurement is applied to the main method of underwater detection.Therefore,a new design scheme of ship draft measurement based on underwater ultrasonic ranging is presented:1 Summarizes the relevant contents of the ship draft inspection,After a lot of work on the field investigation,summarizes and analyzes the current methods of ship drafting.Based on the analysis of the shortcomings of the sonar technology to measure the draft system of the ship,a draft water measurement system based on underwater ultrasonic moving range is proposed.Describes the principle of sonar distance measurement,ship draft calculation and motor control sonar movement.2 Analyzes the functional requirements of the ship draft inspection system,designs the hardware and software part of the system.The hardware part includes the design and debugging of the motor control circuit,such as the minimum system,the power module,the isolation module and the communication module.The software part includes design and realization of the sonar echo data transmission,data format and analysis,data imaging,data display and data preservation.3 Presents an underwater distance measurement method based on echo signal strength and adaptive threshold algorithm,to solve the problem of large fluctuation range and deviation caused by multiple echoes,echo interference and underwater foreign matter.4 Study the calculation method of ship draft value.Based on the change of target ship distance value and the speed of sonar movement measured by sonar,abnormal data filtering is carried out to calculate the draft value of ship.5 Design the corresponding verification experiment,verify the validity of the calculation algorithm and the feasibility of the drafting system,and analyze the error of the experimental results.The experimental results show that the design of ship based on sonar ultrasonic distance measurement,achieve the collection and real-time display of the ship underwater information,and achieve the precise calculation and display of the underwater ship target distance information and draft value,the ship draft monitoring has a certain degree of feasibility,can reduce the number of their own ship and other ships safety incidents.