CN109131771B - Inland ship draft detection system and detection method based on maritime supervision - Google Patents

Inland ship draft detection system and detection method based on maritime supervision Download PDF

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CN109131771B
CN109131771B CN201811046987.5A CN201811046987A CN109131771B CN 109131771 B CN109131771 B CN 109131771B CN 201811046987 A CN201811046987 A CN 201811046987A CN 109131771 B CN109131771 B CN 109131771B
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ship
sinking
pipe
air
floating
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CN109131771A (en
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彭懿
王劼明
盛楚倩
马灵玲
余辉敏
陈新
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Nanjing University of Science and Technology
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Nanjing University of Science and Technology
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B39/00—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude
    • B63B39/12—Equipment to decrease pitch, roll, or like unwanted vessel movements; Apparatus for indicating vessel attitude for indicating draught or load

Abstract

The invention discloses a system and a method for detecting inland ship draught based on maritime supervision. The detection system comprises an inflating and exhausting device, an air guide pipe, a sinking and floating pipe, a signal acquisition system and a data analysis system. The detection method specifically comprises the following steps: firstly, the air charging and discharging device charges air to the air guide pipe, and charges air to the sinking and floating pipe through the small hole of the air guide pipe; floating the floating pipe until the floating pipe is contacted with the bottom of the ship to be measured; the pressure sensors on the sinking and floating pipes detect water pressure values at different positions; the signal amplification device amplifies the electric signal measured by the pressure sensor and transmits the electric signal to the data analysis system; the maximum pressure value can be obtained through the analysis and the processing of the data analysis system, and the draught value of the ship is obtained by utilizing the maximum pressure value; and the air charging and discharging control system controls the air charging and discharging device to discharge air, the sinking and floating pipe sinks into the riverbed, and the detection is finished. The invention has novel detection principle, can realize intelligent and automatic detection of the actual draught value, and is not easily influenced by external factors; the simultaneous detection of multiple ships can be realized, and the practicability is high.

Description

Inland ship draft detection system and detection method based on maritime supervision
Technical Field
The invention relates to the technical field of ship draft detection, ship safety detection and the like, in particular to a system and a method for detecting the draft of an inland ship based on maritime supervision.
Background
Waterway transportation is one of the important components of the transportation mode of China, promotes the rapid and steady development of national economy of China, and drives the rapid growth of economy along the line. However, in order to seek economic benefits, some transport ships do not carry goods according to the water depth maintained by the channel, and methods such as local goods distribution, remote visa, "big ship and small ship", lying draught, water gauge counterfeiting and the like are often adopted for evasive management. When the 'super-draft' ships which run into the channel in violation of regulations risk passing through the shallow risk channel section of the channel, the ships are easy to be stranded in the channel, so that the sediment in the channel is rapidly deposited, the channel is seriously damaged, the channel is damaged, and the normal smooth operation of the channel is influenced. Therefore, draft detection and supervision of ships is one of the main responsibilities of the marine department to maintain and guarantee the normal operation of water transportation.
In order to solve the problems, the invention application 201110133129.6 discloses an automatic detection method of a ship water gauge based on image processing, which combines an image recognition technology, finds out two longest edge lines, namely a water trace line and a waterline, by acquiring a video image of the water gauge, utilizing the characteristic that the relative positions of the water trace line and the waterline in the video image are unchanged, and utilizing edge detection, geometric correction and Hough transformation, and can obtain the real waterline by removing the water trace line positioned above the two lines. The method depends on the accuracy of the water gauge of the ship, is not suitable for marine supervision, and can influence the image recognition in severe environmental factors such as foggy days and storms, thereby causing larger errors.
The invention application 201410854834.9 discloses a side-scanning ship draught detection system and a detection method thereof, wherein an ultrasonic transmitting sensor is started in a time-sharing manner, an ultrasonic receiving array collects signals, whether the receiving sensor is shielded or not is judged, if not, a distance measurement module is started to acquire ship AIS information, and according to a sensor AXAnd AX+1And calculating a specific draft value, averaging if the draft value and the specific draft value are equal, and recalculating the draft value again according to the smoothness of the ship bottom if the draft value and the specific draft value are not equal. Because the ultrasonic ranging value is related to the sound velocity, the measurement precision is directly influenced by the error of the sound velocity, the sound velocity is related to the density of a medium, and the influence of the temperature in the air is large, so that the precision of the ship draft measurement mode is greatly reduced, and the ship draft measurement mode is not suitable for the draft detection of maritime patrol (not on board).
In the existing ship draft detection method, the accuracy of a manual observation method is low, errors are often generated due to improper operation of personnel and subjectivity of the personnel, and the ship draft accuracy is seriously influenced; the pressure sensor is fixedly arranged on the ship for ranging, so that a maritime department is difficult to acquire data and is not suitable for maritime supervision; the electronic water gauge is fixedly arranged on a ship, so that the maintenance is inconvenient, and a maritime department is difficult to acquire data and is not suitable for maritime supervision; the laser water level meter measurement requires detection on a ship to be detected, the laser beam is required to be perpendicular to the water surface during detection, wind waves can affect the detection effect, and the ship is required to be highly accurate and reliable.
Disclosure of Invention
The invention aims to solve the technical problem of providing a river ship draft detection technology and method which are suitable for maritime supervision, high in precision, convenient and quick to operate.
The technical solution for realizing the purpose of the invention is as follows: a inland river ship draft detection system based on maritime supervision comprises an air charging and exhausting device, an air guide pipe, a sinking and floating pipe, a signal acquisition system and a data analysis system; the signal acquisition system comprises N pressure sensors and a signal amplification device; the air duct is arranged in the floating pipe; the N pressure sensors are arranged on the sinking-floating pipe.
The air charging and discharging device is used for charging air into the air guide pipe connected with the air charging and discharging device and controlling the charging time, the discharging time, the charging speed, the discharging speed, the charging time and the discharging time of the air guide pipe;
the gas guide pipe is used for transmitting gas filled in the gas filling and discharging device to realize uniform and rapid gas filling and discharging of the sinking and floating pipe;
the sinking and floating pipe is used for carrying the pressure sensor to float upwards or sink;
the pressure sensor is used for measuring the pressure value of water at the contact point of the pressure sensor and the bottom of the ship;
the signal amplification device is used for amplifying the pressure value of the water measured by the pressure sensor and transmitting the amplified pressure value to a data analysis system;
and the data analysis system is used for calculating the actual draft value of the ship.
The detection method of the inland ship draft detection system based on the maritime supervision comprises the following steps:
step 1, inflating an air guide pipe by an inflating and exhausting device, further inflating a floating pipe to float upwards until the floating pipe contacts the bottom of a ship to be tested, and stopping inflating;
step 2, all the pressure sensors respectively measure the pressure value of water at the position of each pressure sensor;
step 3, amplifying the pressure values of the water respectively measured by all the pressure sensors in the step 2 by a signal amplifying device, and transmitting all the amplified pressure values to a data analysis system;
step 4, the data analysis system analyzes and processes all the amplified pressure values obtained in the step 3 to obtain a maximum pressure value Pmax；
Step 5, utilizing the maximum pressure value P obtained in step 4maxCalculating the actual draft value h of the ship to be measured1；
And 6, exhausting by using an air charging and exhausting device to enable the sinking and floating pipe to sink into the river bed, and finishing detection.
Compared with the prior art, the invention has the following remarkable advantages: 1) the detection system and the detection method have novel detection principle, and the draft of the ship is obtained by acquiring the pressure in an air charging and exhausting mode of the air guide tube with the pressure sensor; 2) the invention can detect the actual draught of the ship in the process of inflating and exhausting the air duct, and is suitable for the requirement of maritime supervision; 3) compared with methods such as water gauge detection and ultrasonic detection, the method can realize intelligent and automatic detection of the actual draught value; 4) the invention can realize the simultaneous detection of multiple ships, has strong practicability and does not influence the traffic capacity of the ship lock.
The present invention is described in further detail below with reference to the attached drawings.
Drawings
Fig. 1 is a schematic view of the exhaust state of the draft detection system of the ship of the present invention. The numbering in the figures represents the meaning: 1-inflating and exhausting device, 2-air duct, 3-sinking and floating tube, 4-pressure sensor, 5-signal amplification device, 6-data analysis system, 7-ship to be tested, and 8-ship bottom.
Fig. 2 is a schematic view of the inflation state of the draft detection system of the ship of the present invention.
FIG. 3 is a partially enlarged schematic view of the connection relationship among the air charging and discharging device, the air duct, the sinking and floating tube and the pressure sensor in the ship draft detecting system according to the present invention.
Fig. 4 is a flow chart of a detection method of the inland river ship draft detection system based on maritime supervision.
FIG. 5 is a schematic diagram of the operation of the test system in an embodiment of the present invention, wherein (a) is the process of inflating the airway tube and (b) is the process of deflating the airway tube.
Detailed Description
With reference to fig. 1, the inland river ship draft detection system based on maritime supervision comprises an air charging and exhausting device 1, an air guide pipe 2, a sinking and floating pipe 3, a signal acquisition system and a data analysis system 6; the signal acquisition system comprises N pressure sensors 4 and a signal amplification device 5; the gas-guide tube 2 is arranged in the sinking-floating tube 3; the N pressure sensors 4 are arranged on the sinking-floating pipe 3.
The air charging and discharging device is used for charging air into the air guide pipe and controlling the charging time, the discharging time, the charging speed, the discharging speed, the charging time and the discharging time of the air guide pipe;
the air guide pipe is used for transmitting the gas filled by the gas filling and discharging device to realize uniform and rapid gas filling and discharging of the sinking and floating pipe;
the sinking and floating pipe is used for carrying the pressure sensor to float upwards or sink;
the pressure sensor is used for measuring the pressure value of water at the contact point of the pressure sensor and the bottom of the ship; because the pressure sensor works in water, the corrosion resistance, the measuring range and the sensitivity of the pressure sensor need to be considered in the selection of the pressure sensor; in order to eliminate the influence of water flow on a pressure signal, a flow dividing cover design of a pressure sensor is adopted;
the signal amplification device is used for amplifying the pressure value of the water measured by the pressure sensor and transmitting the amplified pressure value to the data analysis system;
and the data analysis system is used for calculating the actual draft value of the ship.
The sinking and floating pipe sinks into the river bed in a normal state as shown in fig. 2, and rises under the action of buoyancy when the inflating and exhausting device inflates air as shown in fig. 3.
Further, the length of the air duct is the same as that of the ups and downs pipe.
Further, the length l of the air duct and the ups and downs tubePipeComprises the following steps:
lpipe＝aShip lock+2h
In the formula, aShip lockThe width of the ship lock and the height of the river channel.
Further, the diameters of the sinking and floating pipes are as follows:
Figure BDA0001793544350000041
wherein m is the mass of the sinking-floating pipe, s is the rising height of the sinking-floating pipe, t is the rising time of the sinking-floating pipe, rhoLiquid for treating urinary tract infectionIs the density of water.
The inflation speed of the inflation and exhaust device is as follows:
Figure BDA0001793544350000042
the exhaust speed is:
Figure BDA0001793544350000043
in the formula, Q is the aeration quantity of the sinking and floating pipe,
Figure BDA0001793544350000044
tcharging deviceTime of inflation of the immersed tube, tRow boardD' is the inner diameter of the sinking and floating pipe.
Furthermore, small holes with the same size are unevenly distributed on the air duct, the small holes are sparse in the area close to the air charging and discharging device, and the small holes are dense in the area far away from the air charging and discharging device.
Further, the sparse and dense degree of the small hole distribution on the air duct and the position relation between the small hole distribution and the distance of the air charging and discharging device are as follows:
Figure BDA0001793544350000051
wherein n is the nth small hole which starts to count near one end of the air charging and discharging device, anThe interval length between the nth-1 small hole and the nth small hole is set; in common with
Figure BDA0001793544350000052
A small hole.
Further, the pressure sensors are uniformly arranged on the sinking-floating pipe, and the arrangement interval d of the pressure sensors1Comprises the following steps:
Figure BDA0001793544350000053
with reference to fig. 4, a detection method based on the inland river ship draft detection system based on maritime supervision includes the following steps:
step 1, inflating an air guide pipe by an inflating and exhausting device, further inflating a floating pipe to float upwards until the floating pipe contacts the bottom of a ship to be tested, and stopping inflating;
step 2, all the pressure sensors respectively measure the pressure value of water at the position of each pressure sensor;
step 3, amplifying the pressure values of the water respectively measured by all the pressure sensors in the step 2 by a signal amplifying device, and transmitting all the amplified pressure values to a data analysis system;
step 4, the data analysis system analyzes and processes all the amplified pressure values obtained in the step 3 to obtain a maximum pressure value Pmax；
Step 5, utilizing the maximum pressure value P obtained in step 4maxCalculating the actual draft value h of the ship to be measured1(ii) a The formula used is:
Figure BDA0001793544350000054
where ρ is the density of water, ρ is obtained by a liquid density sensor.
And 6, exhausting by using an air charging and exhausting device to enable the sinking and floating pipe to sink into the river bed, and finishing detection.
Examples
The invention relates to a maritime supervision-based inland ship draft detection system, which comprises a sinking and floating pipe, an air guide pipe, an air charging and exhausting device, an air charging and exhausting control system, a signal acquisition system and a data analysis system. In this embodiment:
(1) the lengths of the air duct and the floating pipe are the same as each otherPipeIn this example,. lPipe＝10m。
(2) The diameter of the sinking and floating pipe considers that the air pipe can be subjected to resistance f in water, the mass m of the air pipe is 20kg, and the length l of the air pipePipeWhen the rising height s is 5m and the rising time t is 10s, 10m, the following results are obtained:
Figure BDA0001793544350000061
the pipe diameter of the sinking and floating pipe finally selected for the test is 6.5cm according to the pipe diameter size which can be provided in the market.
(3) The charging speed of the charging and discharging device is
Figure BDA0001793544350000062
Exhaust velocity of
Figure BDA0001793544350000063
Figure BDA0001793544350000064
Wherein, the aeration quantity of the sinking and floating pipe
Figure BDA0001793544350000065
The inflation time is assumed as the rising time t of the floating pipeCharging deviceExhaust time of tRow boardAnd d' is the inner diameter of the sinking and floating pipe. Through the operation of the test system, the inflation time tCharging deviceExhaust time t of 27sRow boardThe inner diameter d' of the ups and downs pipe is 1.8cm for 20s, and the inflation quantity Q of the ups and downs pipe is 30622.85cm3，vCharging device＝1134.18cm3/s，vRow board＝1531.14cm3/s。
(4) The signal acquisition system comprises N pressure sensors, wherein N is 20 in the embodiment, and the arrangement interval d of the pressure sensors1Comprises the following steps:
Figure BDA0001793544350000066
the parameters of the system for testing in this example are shown in table 1 below, and the operation of the test system is shown in fig. 5.
TABLE 1 test System parameters
Figure BDA0001793544350000067
The inland river ship draft detection system based on the maritime supervision detects the inland river ship draft detection system, and comprises the following contents:
(1) the exhaust device inflates the air guide pipe, and then inflates the floating pipe to float upwards until the floating pipe contacts the bottom of the ship to be tested, and the inflation is stopped;
(2) all the pressure sensors respectively measure the pressure value of water at the position of each pressure sensor;
(3) the signal amplification device amplifies the pressure values of the water measured by all the pressure sensors in the step (2) respectively and transmits all the amplified pressure values to a data analysis system;
(4) analyzing and processing (3) all the amplified pressure values by the data analysis system to obtain a maximum pressure value Pmax；
(5) Maximum pressure value P obtained by (4)maxCalculating the actual draft value h of the ship to be measured1；
(6) And exhausting by the air charging and exhausting device to enable the sinking and floating pipe to sink into the river bed, and finishing detection.
The test results are shown in table 2 below. According to the characteristics of the sensor, the draught value can be known by the output voltage of the sensor. The principle test result shows that the ascending and descending of the air pipe work smoothly, and the ascending and descending speed slightly comes in and goes out from the theoretical value.
TABLE 2 test results
Figure BDA0001793544350000071
It can be seen that the relative error of the data is within the allowable range, which is related to the range of the selected pressure sensor, the data acquisition equipment and other factors.
The detection principle of the invention is novel, the pressure is obtained by adopting the air charging and discharging mode of the air guide tube with the pressure sensor, so that the draft depth of the ship is obtained, the intelligent and automatic detection of the actual draft value can be realized, and the influence of external factors is not easy to influence; the simultaneous detection of multiple ships can be realized, and the practicability is high.

Claims (7)

1. A inland river ship draught detection system based on maritime supervision is characterized by comprising an air charging and exhausting device (1), an air guide pipe (2), a sinking and floating pipe (3), a signal acquisition system and a data analysis system (6); the signal acquisition system comprises N pressure sensors (4) and a signal amplification device (5); the gas-guide tube (2) is arranged in the sinking-floating tube (3); the N pressure sensors (4) are arranged on the sinking-floating pipe (3);
the air charging and discharging device is used for charging air into the air guide pipe connected with the air charging and discharging device and controlling the charging time, the discharging time, the charging speed, the discharging speed, the charging time and the discharging time of the air guide pipe;
the gas guide pipe is used for transmitting gas filled in the gas filling and discharging device to realize uniform and rapid gas filling and discharging of the sinking and floating pipe;
the sinking and floating pipe is used for carrying the pressure sensor to float upwards or sink;
the pressure sensor is used for measuring the pressure value of water at the contact point of the pressure sensor and the bottom of the ship;
the signal amplification device is used for amplifying the pressure value of the water measured by the pressure sensor and transmitting the amplified pressure value to a data analysis system;
and the data analysis system is used for calculating the actual draft value of the ship.
2. The marine surveillance-based inland vessel draft detection system according to claim 1, wherein said gas-guide tube and sinking-floating tube are of the same length.
3. The marine surveillance-based inland vessel draft detection system according to claim 2, wherein said gas-guide tube and sinking-floating tube have a length lPipeComprises the following steps:
lpipe＝aShip lock+2h
In the formula, aShip lockWidth of ship lockDegree, h is the height of the river.
4. The marine surveillance-based inland vessel draft detection system according to claim 1 or 3, wherein the air duct is unevenly distributed with pores of the same size, wherein the pores are sparse in a region close to the inflation and deflation device and dense in a region far from the inflation and deflation device.
5. The inland vessel draft detection system based on maritime supervision according to claim 3, wherein the sparse and dense degree of the distribution of the small holes on the gas-guide tube and the position relation of the gas-filled exhaust device are as follows:
Figure FDA0002479230110000011
wherein n is the nth small hole which starts to count near one end of the air charging and discharging device, anThe interval length between the nth-1 small hole and the nth small hole is set; in common with
Figure FDA0002479230110000012
A small hole.
6. The inland vessel draft detection system based on maritime supervision according to claim 3, wherein said pressure sensors are uniformly installed on the sinking-floating pipe, and the arrangement interval d of the pressure sensors is1Comprises the following steps:
Figure FDA0002479230110000021
in the formula, N is the number of the pressure sensors.
7. A detection method of the inland river ship draft detection system based on maritime supervision according to claim 1, which is characterized by comprising the following steps:
step 1, inflating an air guide pipe by an inflating and exhausting device, further inflating a floating pipe to float upwards until the floating pipe contacts the bottom of a ship to be tested, and stopping inflating;
step 2, all the pressure sensors respectively measure the pressure value of water at the position of each pressure sensor;
step 3, amplifying the pressure values of the water respectively measured by all the pressure sensors in the step 2 by a signal amplifying device, and transmitting all the amplified pressure values to a data analysis system;
step 4, the data analysis system analyzes and processes all the amplified pressure values obtained in the step 3 to obtain a maximum pressure value Pmax；
Step 5, utilizing the maximum pressure value P obtained in step 4maxCalculating the actual draft value h of the ship to be measured1；
And 6, exhausting by using an air charging and exhausting device to enable the sinking and floating pipe to sink into the river bed, and finishing detection.
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