Modularized extensible side scanning type draught detection system

Abstract

The invention discloses a modular extensible side-scan draught detection system, which comprises M detection modules and a water level gauge, each detection module comprises a transmitting end module and a receiving end module, the transmitting end module comprises N ultrasonic transmitters, and the receiving end module comprises N ultrasonic receivers. The sending end module and the receiving end module can be combined according to different detection range requirements. And each group of sending end module and receiving end module is combined with a system master control end, and the system is suitable for a shipping hub in a detection range of 0-3m. The modular extensible design enables the system to quickly adjust the number of detection modules according to actual requirements, and the flexibility and commercial value of the system are improved. According to the method, the research and development cost caused by specific design for different shipping hubs is reduced, different selections can be made according to specific requirements of the shipping hubs, and the early-stage material input cost is greatly reduced.

Description

Technical Field

[0001] The invention relates to the technical field of ship draft detection, in particular to a modular and expandable side-scanning draft detection system. Background Art

[0002] Existing side-scan draft detection systems usually use an array of ultrasonic transmitters and an array of ultrasonic receivers fixed on a mounting frame, which are deployed underwater in the waterway to measure the draft depth of the ship. These systems can provide continuous monitoring data, but their adaptability to waterways of different depths and widths is limited. With the development of the shipping industry and the trend of larger ships, the threshold water depth requirements for waterways are increasing, resulting in an increase in the range of ship draft depths. In order to adapt to this change, the traditional solution is to directly design a detection system that can carry more pairs of ultrasonic transmitters and ultrasonic receivers to expand the range of the side-scan draft detection system.

[0003] The disadvantages of the above method are:

[0004] The current side-scanning draft detection system needs to deploy a large number of ultrasonic transmitters and ultrasonic receivers when dealing with large-scale draft depth detection, which not only increases the initial investment cost of the system, but also leads to a significant increase in maintenance difficulty and maintenance cost due to the increase in the number of ultrasonic transmitters and ultrasonic receivers. In addition, the synchronization and data processing of a large number of ultrasonic transmitters and ultrasonic receivers have become more complicated, affecting the stability and reliability of the system. At the same time, the deployment of large-scale ultrasonic transmitter arrays and ultrasonic receiver arrays is also a challenge for energy consumption, especially in terms of power consumption and environmental adaptability. Therefore, this method has obvious shortcomings in terms of economic benefits and operational convenience. Summary of the invention

[0005] In order to solve the above problems existing in the prior art, the present invention designs a modular and expandable side-scanning draft detection system with high ultrasonic sensor utilization efficiency and wide longitudinal measurement range.

[0006] In order to achieve the above-mentioned object, the technical scheme of the present invention is as follows: a modular and expandable side-scanning draft detection system, comprising M detection modules and a water level gauge, each detection module comprising a transmitting end module and a receiving end module; the M transmitting end modules are installed in series on one side of the waterway, and the M receiving end modules are installed in series on the other side of the waterway; each detection module realizes a detection range of 2.5-3.0m water depth;

[0007] The transmitting end module includes N ultrasonic transmitters, a transmitting end bracket and an FPGA transmitting end circuit board. The N ultrasonic transmitters are installed on the transmitting end bracket to form an ultrasonic transmitter array; the FPGA transmitting end circuit board is fixedly installed on the transmitting end bracket to control the ultrasonic transmitter array to transmit ultrasonic waves;

[0008] The receiving end module includes N ultrasonic receivers, a receiving end bracket and an FPGA receiving end circuit board, wherein the N ultrasonic receivers are mounted on the receiving end bracket to form an ultrasonic receiver array; the FPGA receiving end circuit board is fixedly mounted on the receiving end bracket to control the ultrasonic receiver array to receive ultrasonic waves;

[0009] The transmitting end module and the receiving end module are installed at the same water depth;

[0010] The data lines of the FPGA receiving end circuit boards of the M receiving end modules are connected in parallel to the host computer via the main control end circuit board;

[0011] The water level meter is installed at the bottom of the lowest receiving end module, and the data line of the water level meter is connected to the host computer via the main control end circuit board.

[0012] Furthermore, the M is 1-4; and the N is 15-20.

[0013] Furthermore, the FPGA transmitting end circuit board includes a driving module for N ultrasonic transmitters, which is responsible for driving the ultrasonic sensor; the FPGA receiving end includes an N ultrasonic receiver signal conversion module, which is responsible for amplifying the received signal and performing analog-to-digital conversion, converting the analog signal into a digital signal for processing by the FPGA chip.

[0014] Furthermore, the main control end circuit board is fixedly installed near the receiving end circuit board, and is used to receive data information sent by the FPGA receiving end circuit board; the main control end circuit board has data processing capabilities, and summarizes and analyzes the received data. The main control end circuit board contains necessary interfaces and communication protocols to ensure that data is accurately transmitted from the FPGA receiving end circuit board to the main control end circuit board, and is processed accordingly. The processed data will be sent to the host computer for further analysis and display.

[0015] The water level meter is used to measure the distance between the bottom of the channel and the water surface in real time. The water level meter is connected to the main control end circuit board through a 485 communication line, and the collected data is sent to the host computer, which calculates the draft value based on the received water level meter data and the ultrasonic receiver occlusion. The host computer is connected to the main control end circuit board through an optical fiber, is responsible for receiving the processed signal data, and performs further data processing and analysis to determine the draft depth of the ship.

[0016] Furthermore, the FPGA transmitting end circuit board integrates a power supply module, a voltage conversion module and an ultrasonic driving module, and the FPGA receiving end circuit board integrates a power supply module, a voltage conversion module and an ultrasonic signal processing module.

[0017] Furthermore, the main control end circuit board integrates an FPGA main control chip, a power supply module, a voltage conversion module and 17 TTL-485 conversion chips to achieve high-speed data exchange with the FPGA transmitter circuit board and the FPGA receiver circuit board, as well as communication with the host computer.

[0018] Furthermore, the working method of the side-scanning draft detection system comprises the following steps:

[0019] A. The FPGA transmitting circuit board controls the ultrasonic transmitter array to transmit ultrasonic signals;

[0020] B. The FPGA receiving circuit board collects the signals collected by the ultrasonic receiver array and transmits them to the main control circuit board; let the distance between two adjacent ultrasonic receivers be L, so the distance H1 from the first ultrasonic receiver to the last ultrasonic receiver is expressed as:

[0021] H1=(M*N-1)*L (1)

[0022] C. During the measurement process, if the Xth ultrasonic transmitter is blocked, the distance H2 from the first ultrasonic transmitter to the Xth ultrasonic transmitter is expressed as:

[0023] H2=(X-1)*L (2)

[0024] D. The main control end circuit board processes the received signal and combines the water level data H provided by the water level meter and the shielding condition H2 of the ultrasonic transmitter to calculate the draft d of the ship:

[0025] d==H-H1+H2 (3)

[0026] E. The main control end circuit board sends the processing results to the host computer through optical fiber for further analysis and recording;

[0027] F. The host computer determines whether the ship has passed the detection based on the received data, including the water level data H, the total distance H1 of the ultrasonic transmitter array, and the distance H2 of the blocked ultrasonic transmitter, and sends corresponding control instructions.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The side-scanning draft detection system of the present invention adopts a modular design. Each detection module includes a transmitter module and a receiver module, which can work independently and cover a water depth range of 2.5-3.0 meters. The transmitter module and the receiver module can be combined according to different detection range requirements. A group of transmitter modules and receiver modules are combined with a system master control terminal, which is suitable for shipping hubs with a detection range of 0-3m. Two groups of transmitter modules and receiver modules are combined with a system master control terminal, which is suitable for shipping hubs with a detection range of 0-5m. A maximum of four groups of transmitter modules and receiver modules can be combined with a system master control terminal to achieve 0-10m draft range detection, greatly improving the longitudinal measurement range and scope of application of the system. At the same time, the modular and expandable design allows the system to quickly adjust the number of detection modules according to actual needs, thereby improving the flexibility and commercial value of the system. This design reduces the R&D costs caused by specific designs, and can be quickly deployed and adjusted according to the needs of navigation hubs, thereby improving the commercial value and market competitiveness of the system.

[0030] 2. The present invention reduces the R&D costs caused by the need for specific designs for different shipping hubs, and can be selected according to the specific needs of the navigation hub, greatly reducing the initial material investment costs. For example, a detection system that can carry 60 sets of ultrasonic transmitters and ultrasonic receivers is directly designed. Although the system can also detect draft values ​​for different navigation hubs, the problems it brings are as follows: for example, if the system is installed in a navigation hub that only needs 20 sets to meet the detection needs, more than half of the components on the system circuit board are actually idle. Therefore, this method leads to a large number of useless components, increases the initial raw material investment cost, and is bound to increase the size of the circuit board, which increases the difficulty of actual installation of the subsequent system. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the multi-module structure of the present invention (three modules connected in series).

[0032] Figure 2 This is a schematic diagram of a single module structure of the present invention.

[0033] Figure 3 This is a schematic diagram of measuring the draft value of a ship according to the present invention.

[0034] Figure 4 This is a schematic diagram of the system PCB modularization (4 modules connected in series).

[0035] In the figure: 1. FPGA transmitter circuit board, 2. FPGA receiver circuit board, 3. Ultrasonic transmitter array, 4. Ultrasonic receiver array, 5. General control end circuit board, 6. 485 communication line, 7. Optical fiber, 8. Transmitter bracket, 9. Host computer, 10. Water level meter, 11. Ship, 12. Receiver bracket. DETAILED DESCRIPTION

[0036] In order to make the technical solution and advantages of the present invention more clear, the technical solution of the present invention is clearly and completely described below in conjunction with the accompanying drawings.

[0037] like Figure 1-4 As shown, the present invention is suitable for installation near engineering sites such as dams, and implements a draft test on the ship 11 before the ship 11 enters the dam, so as to facilitate timely interception of ships 11 with unqualified draft, and effectively prevent the risk of accidents caused by excessive draft of the ship 11.

[0038] Because the installation site environment may be very complex, in order to ensure the reliability of data during transmission, the present invention uses optical fiber 7 as the medium for transmitting signals. Optical fiber 7 has the characteristics of strong anti-interference ability, fast transmission speed, and long transmission distance, and can ensure the timeliness and accuracy of data transmission.

[0039] In the specific implementation process, the FPGA transmitting end circuit board 1 controls the ultrasonic transmitter array 3 to transmit ultrasonic signals, which are reflected back after encountering the water surface or underwater objects and received by the ultrasonic receiver array 4. The received signal is then transmitted to the FPGA receiving end circuit board 2 for preliminary processing. At the same time, the water level meter 10 measures the distance between the bottom of the waterway and the water surface in real time, and sends the water level data directly to the main control end circuit board 5 through the 485 communication line. The main control end circuit board 5 summarizes the ultrasonic signal data from the FPGA receiving end circuit board 2 and the water level data of the water level meter 10 for comprehensive processing.

[0040] The processed data is sent to the host computer 9 via the optical fiber 7. The host computer 9 receives and analyzes the data processing results transmitted by the main control end circuit board 5, and at the same time, combines the information provided by the ship automatic identification system (AIS) to comprehensively evaluate the draft value of the ship 11. The host computer 9 will also calculate the actual draft value of the ship 11 based on the water level provided by the water level meter 10 and the shielding of the ultrasonic transmitter array 3. Although the AIS system can provide the real-time draft value of the ship, due to its high environmental requirements and low reliability, especially the low detection accuracy and poor real-time performance of the low-speed ship 11, the system of the present invention can serve as a powerful supplement to the AIS and provide more accurate and reliable draft detection data. Through the real-time water level data of the water level meter 10, the host computer 9 can more accurately calculate the draft value of the ship 11 to ensure the safety of the waterway.

[0041] According to the working principle of the present invention, the ultrasonic transmitter at the transmitting end on the left side of the channel sends out an ultrasonic signal, and the ultrasonic receiver at the receiving end on the right side of the channel receives the ultrasonic signal. Since the wavelength of the sound wave is much smaller than the distance between the two, this phenomenon is closer to Fresnel straight edge diffraction.

[0042] The principle of Fresnel straight edge diffraction is that when sound waves pass through the edge of an object, the existence of the object will cause some changes in wave impedance in the propagation direction of the sound waves. This change in wave impedance will cause interference and diffraction of the sound waves, forming a series of light and dark stripes.

[0043] The obvious characteristic of this phenomenon is that when the navigable ship 11 passes through the detection system, the ultrasonic transmitter signal is blocked by it, forming a shadow area behind it. However, the ultrasonic transmitter signal that is not blocked will continue to propagate, forming a bright area opposite to the blocked area. At the junction of the bright area and the shadow area, there is a sound intensity that is not zero.

[0044] According to the Fresnel diffraction formula, the diffraction field distribution at any point on the receiving screen is the superposition of the infrasound source sound field:

[0045]

[0046] The integral range M in the above formula is the unobstructed part of the sound wave emitted by the sound source S, C is a complex constant, K(θ) is the tilt factor, r0 is the distance from the point source to the surface element, r is the distance from point P to the surface element on the wavefront M, Represents a spherical wave with a complex amplitude of A(Q) emitted by the infrasound source on the wave front.

[0047] Further, there are:

[0048]

[0049] Where λ is the wave number of the sound wave, z is the distance from the sound source S to the straight-edge obstruction, and F(x) is the Fresnel equation, which is specifically expressed as:

[0050]

[0051] The formula for calculating the sound wave intensity is:

[0052] I=|E(x,y)| 2 (8)

[0053] Based on the analysis of Fresnel straight edge diffraction characteristics, the type of ultrasonic transmitters and the installation spacing between them can be determined.

[0054] The ultrasonic transmitter of the present invention is only used to transmit sound waves, and the ultrasonic receiver is only used to receive sound waves. Both contain piezoelectric ceramic crystals, so they are also called piezoelectric sensors. The piezoelectric effect refers to the phenomenon that certain crystal materials will produce changes in charge distribution when subjected to mechanical pressure or deformation, thereby generating a potential difference and an electric field. Conversely, when an electric field is applied to these crystals, deformation or mechanical deformation will occur. The characteristic of the positive piezoelectric effect of the piezoelectric sensor is that when the piezoelectric sensor receives an ultrasonic signal, the piezoelectric ceramic inside will be positively polarized to generate an electrical signal. The characteristic of the reverse voltage effect is that when an electric field is applied to the two poles of the piezoelectric ceramic crystal, vibration will occur, thereby emitting ultrasonic waves.

[0055] like Figure 1-3 As shown, the PCB module mainly consists of the following parts:

[0056] 1. FPGA transmitter circuit board: responsible for controlling the transmission signal of the ultrasonic transmitter array. The FPGA transmitter circuit board ensures the effective transmission of ultrasonic signals through precise timing control, which is the key to realizing the draft detection function.

[0057] 2. FPGA receiving circuit board: Corresponding to the transmitting circuit board, the receiving circuit board is mainly responsible for receiving the signal collected by the ultrasonic receiver array. It amplifies and converts the received analog signal to provide a digital signal for subsequent data processing.

[0058] 3.485 communication line: 485 communication line adopts differential signal transmission mode, which has good anti-interference ability and long transmission distance. In this system, 485 communication line is used to connect the receiving end circuit board with the main control end circuit board to achieve stable data transmission.

[0059] 4. General control end circuit board: The general control end circuit board is responsible for coordinating the work of the FPGA transmitter and receiver, and summarizing and processing the collected data. It is connected to the host computer through optical fiber to exchange data and ensure the real-time and accuracy of the data.

[0060] The present invention has embodiments as follows:

[0061] The present invention is installed at the entrance of a navigable dam, and a geographical location suitable for installation is found. The installation of the present invention requires vertical building structures underwater on both sides of the navigable waterway. It is most appropriate to install the present invention near the anti-collision beam of the navigable dam, because there are mostly large-scale vertical flat structures artificially built near the anti-collision beam, or other suitable locations for installing the system can be found near the entrance of the navigable dam.

[0062] When the ship 11 is about to pass through the shipping hub, the FPGA transmitting end circuit board 1 controls the ultrasonic transmitter array 3 to transmit ultrasonic signals. The FPGA receiving end circuit board 2 is responsible for collecting the signals collected by the ultrasonic receiver array 4 and transmitting these signals to the main control end circuit board 5 for processing.

[0063] The water level meter 10 records the water level height H in real time. At the same time, the distance from the first ultrasonic transmitter to the last ultrasonic transmitter in the ultrasonic transmitter array is H1. When the ship 11 passes through the detection system, some ultrasonic transmitters may be blocked, and the distance H2 of the blocked part of the ultrasonic transmitter. The calculation of the draft depth (d) no longer depends on the measurement of the ultrasonic round trip time, but is determined by the following formula:

[0064] d=H-H1+H2 (9)

[0065] Wherein, H is the water level recorded by the water level meter 10, H1 is the distance from the first ultrasonic transmitter to the last ultrasonic transmitter of the ultrasonic transmitter array, and H2 is the distance of the shielded portion of the ultrasonic transmitter caused by the ship's travel.

[0066] The main control end circuit board 5 sends the processed data to the host computer 9 through the optical fiber 7. The host computer 9 receives and analyzes the data transmitted by the main control end circuit board 5, and performs a comprehensive evaluation in combination with other relevant data to determine whether the ship 11 is suitable for passing through the waterway. Through the real-time water level data of the water level meter 10 and the sensor shielding of the ultrasonic transmitter array 4, the host computer 9 can more accurately calculate the draft value of the ship 11 to ensure the safety of the waterway.

[0067] The present invention is not limited to this embodiment, and any equivalent concepts or changes within the technical scope disclosed by the present invention are included in the protection scope of the present invention.

Claims

1. A modular and scalable side-scanning draft detection system, characterized by: It comprises M detection modules and a water level meter (10), each detection module comprising a transmitting end module and a receiving end module; the M transmitting end modules are installed in series on one side of the waterway, and the M receiving end modules are installed in series on the other side of the waterway; each detection module realizes a detection range of 2.5-3.0 m water depth; The transmitting end module comprises N ultrasonic transmitters, a transmitting end bracket (8) and an FPGA transmitting end circuit board (1); the N ultrasonic transmitters are mounted on the transmitting end bracket (8) to form an ultrasonic transmitter array (3); the FPGA transmitting end circuit board (1) is fixedly mounted on the transmitting end bracket (8) and is used to control the ultrasonic transmitter array (3) to transmit ultrasonic waves; The receiving end module comprises N ultrasonic receivers, a receiving end bracket (12) and an FPGA receiving end circuit board (2); the N ultrasonic receivers are mounted on the receiving end bracket (12) to form an ultrasonic receiver array (4); the FPGA receiving end circuit board (2) is fixedly mounted on the receiving end bracket (12) and is used to control the ultrasonic receiver array (4) to receive ultrasonic waves; The transmitting end module and the receiving end module are installed at the same water depth; The data lines of the FPGA receiving end circuit boards (2) of the M receiving end modules are connected in parallel and then connected to a host computer (9) via a general control end circuit board (5); The water level meter (10) is installed at the bottom of the lowest receiving end module, and the data line of the water level meter (10) is connected to the host computer (9) via the main control end circuit board (5).

2. According to claim 1, a modular and expandable side-scanning draft detection system, characterized in that: The M is 1-4; the N is 15-20.

3. According to claim 1, a modular and expandable side-scanning draft detection system, characterized in that: The FPGA transmitting end circuit board (1) comprises N-channel ultrasonic transmitter driving modules, which are responsible for driving the ultrasonic sensor to work; the FPGA receiving end comprises N-channel ultrasonic receiver signal conversion modules, which are responsible for amplifying the received signals and performing analog-to-digital conversion, and converting the analog signals into digital signals for processing by the FPGA chip.

4. According to claim 1, a modular and expandable side-scanning draft detection system, characterized in that: The main control end circuit board (5) is fixedly installed near the receiving end circuit board and is used to receive data information sent by the FPGA receiving end circuit board (2); the main control end circuit board (5) has data processing capabilities and summarizes and analyzes the received data; the main control end circuit board (5) includes necessary interfaces and communication protocols to ensure that data is accurately transmitted from the FPGA receiving end circuit board (2) to the main control end circuit board (5) and is processed accordingly; The processed data will be sent to the host computer (9) for further analysis and display; The water level meter (10) is used to measure the distance between the bottom of the waterway and the water surface in real time; the water level meter (10) is connected to the main control end circuit board (5) via a 485 communication line (6) and sends the collected data to the host computer (9), and the host computer (9) calculates the draft value according to the received water level meter (10) data and the shielding condition of the ultrasonic receiver; the host computer (9) is connected to the main control end circuit board (5) via an optical fiber (7), is responsible for receiving the processed signal data, and performs further data processing and analysis to determine the draft depth of the ship (11).

5. According to claim 1, a modular and expandable side-scanning draft detection system is characterized by: The FPGA transmitting end circuit board (1) integrates a power supply module, a voltage conversion module and an ultrasonic driving module, and the FPGA receiving end circuit board (2) integrates a power supply module, a voltage conversion module and an ultrasonic signal processing module.

6. The modular and expandable side-scanning draft detection system according to claim 1, characterized in that: The master control end circuit board (5) integrates an FPGA main control chip, a power supply module, a voltage conversion module and 17 TTL-485 conversion chips to achieve high-speed data exchange with the FPGA transmitting end circuit board (1) and the FPGA receiving end circuit board (2), as well as communication with a host computer (9).

7. The modular and expandable side-scanning draft detection system according to claim 1, characterized in that: The working method of the side-scanning draft detection system comprises the following steps: A. The FPGA transmitting end circuit board (1) controls the ultrasonic transmitter array (3) to transmit ultrasonic signals; B. The FPGA receiving end circuit board (2) collects the signals collected by the ultrasonic receiver array (4) and transmits them to the main control end circuit board (5); assuming that the distance between two adjacent ultrasonic receivers is L, the distance H1 from the first ultrasonic receiver to the last ultrasonic receiver is expressed as: H1=(M*N-1)*L (1) C. During the measurement process, if the Xth ultrasonic transmitter is blocked, the distance H2 from the first ultrasonic transmitter to the Xth ultrasonic transmitter is expressed as: H2=(X-1)*L (2) D. The main control end circuit board (5) processes the received signal and combines the water level data H provided by the water level meter (10) and the shielding condition H2 of the ultrasonic transmitter to calculate the draft d of the ship (11) using the formula: d==H-H1+H2 (3) E. The main control end circuit board (5) sends the processing results to the host computer (9) through the optical fiber (7) for further analysis and recording; F. The host computer (9) determines whether the ship (11) has passed the detection based on the received data, including the water level data H, the total distance H1 of the ultrasonic transmitter array (3), and the distance H2 of the blocked part of the ultrasonic transmitter, and sends a corresponding control instruction.

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