JP2020003431A5 - - Google Patents

Description

A method for detecting surface changes by ultrasonic waves and a system for detecting surface changes by ultrasonic waves

The present invention relates to a method for detecting a surface change state by ultrasonic waves, which detects a change state including an adhesion state of deposits on a structure using ultrasonic waves, and a system for detecting a surface change state by ultrasonic waves.

Adhesion of marine organisms such as barnacles to the surface of the hull significantly increases hull resistance during propulsion. In addition, "cross-border organisms", in which marine organisms attach to the hull of a ship, move, and fall off and propagate in places away from their original habitat, are also regarded as a problem.
At present, most of the observations of marine organisms attached to the hull are carried out visually after dry-up (drainage) at the time of docking the repair dock. It is possible to observe by taking an image of the bottom of the ship with a diver or ROV (remotely operated vehicle), but it is difficult to observe while the ship is sailing, and the timing of observation is limited.

Here, in Patent Document 1, a pair of probes for transmitting and receiving ultrasonic flaw detectors are symmetrically applied to the outside of the tube to be inspected, ultrasonic pulses are transmitted, and received pulses are generated. Disclosed is a method of measuring the adhesion of marine organisms inside a pipe by comparing the waveform of the above with the waveform for a healthy pipe. Further, in Patent Document 1, an ultrasonic flaw detector probe is applied to a point on the outside of the tube to be inspected, an echo from the tube body and an echo from the surface of the marine organism are measured, and an echo from the surface of the marine organism is measured. Also disclosed is a method of measuring the adhesion thickness of marine organisms inside a pipe by reading the propagation distance of.
Further, in Patent Document 2, an ultrasonic transmitter and a receiver are arranged to face each other with a predetermined gap from the outer wall of the pipe, and the gap is filled with an acoustic bonding liquid of the same type as the fluid in the pipe. Ultrasonic waves are propagated into the fluid toward the receiver to detect the ultrasonic attenuation ratio, and the detected value and the calibration value of the ultrasonic attenuation factor obtained for the known scale thickness in advance are calculated into the pipe. A method for determining the thickness of the attached scale is disclosed.
Further, in Patent Document 3, a scanning body in which an ultrasonic wave transmitter / receiver is attached to a guide bar fixed to a frame body having a support leg is slidably supported, and ultrasonic waves are transmitted from the ultrasonic wave transmitter / receiver at regular intervals. The scanning body is moved while emitting a pulse signal, the emitted pulse signal is received by an ultrasonic transmitter / receiver, and the time difference between the emitted signal and the received signal is detected and known. The distance between the ultrasonic transmitter and receiver and the marine adult is calculated from the sound velocity and time difference of the ultrasonic wave, and the layer thickness of the marine adult is calculated from the distance between the known ultrasonic transmitter and receiver and the base, and the layer thickness of the marine adult is calculated at the signal emission point. An apparatus for measuring and scanning the layer thickness of marine adults is disclosed.

Japanese Unexamined Patent Publication No. 3-188390 Japanese Unexamined Patent Publication No. 62-54113 Jitsufuku No. 3-8967 Gazette

However, with the methods or devices described in Patent Documents 1 to 3, it is difficult to detect, for example, the state of adhesion of deposits on the outer surface of the hull from the inside of the hull for the following reasons.
Of the methods described in Patent Document 1, the first method described above and the method described in Patent Document 2 use ultrasonic waves using two ultrasonic sensors for transmission and reception, which are arranged so as to face each other across a tube. The state of adhesion of deposits adhering to the inside of the pipe is detected by the attenuation of the transmitted wave. However, when trying to detect deposits on the outer surface of the hull from the inside of the hull, it is difficult to install an ultrasonic sensor for reception outside the hull.
Of the methods described in Patent Document 1, the second method described above and the apparatus described in Patent Document 3 use the ultrasonic Time of Flight method (TOF method) to adhere to the thickness of deposits adhering to the inside of the pipe. It measures the patent. However, when attempting to detect deposits on the outer surface of the hull from the inside of the hull, the deposit surface (outer surface of the hull) is the surface immediately opposite to the surface (surface inside the hull) with which the ultrasonic sensor is contacted. As a result, the reflected echo from the adhering surface and the reflected echo due to the adhering material are superimposed and measured, so that the starting point of the echo due to the adhering material becomes unclear, and it is difficult to apply the TOF method.

The present invention is, for example changing circumstances, including the adhesion state of the deposit to the hull outer surface even from the hull interior to allow detection, a change situation, including the adhesion state of the deposit on one surface of the structure, can be detected by the incident ultrasonic waves from the other surface which is in relation of one surface inextricably linked, the detection method of a change situation of the surface by ultrasound, and provides a detection system changes the status of the surface by ultrasonic The purpose is.

In the method for detecting the surface change status by ultrasonic waves according to the first aspect, the surface change status is detected by detecting the surface change status including the adhesion status of the deposits to the structure by using ultrasonic waves. In the method, at the first time, ultrasonic waves are incident on the structure and the first reflected echo is measured, and at the second time, ultrasonic waves are incident on at least the structure and the second reflected echo is measured. The adhesion status of deposits to the structure is compared by comparing the integrated value or power spectrum of the first reflected echo and the second reflected echo, or based on the deviation of the waveforms of the first reflected echo and the second reflected echo. It is characterized by detecting the change situation including.
In addition, the deposits include foreign deposits, those in which the deposits have grown, those in which the deposits have precipitated from the surroundings, those in which the structure has undergone a chemical change and the surface of the structure has become a deposit.
According to the first aspect of the present invention, for comparison of the integrated value or power spectrum of the first reflected echo and the second reflected echo, or for the deviation of the waveforms of the first reflected echo and the second reflected echo. by detecting a change situation, including the adhesion state on the basis of the other surface with a change situation, including the adhesion state of the deposit on one surface of the structure, for example, the relationship between the one surface inextricably linked It can be detected from the side. As a result, for example, the change status including the presence or absence of deposits on the outer surface of the hull can be detected even from the inside of the hull, so that the deposits adhere to the outer surface of the hull regardless of whether it is moored or sailing. It will be possible to monitor the change situation including the situation in a timely manner.

The present invention according to claim 2 is characterized in that a first reflected echo at a first time is measured and recorded in advance, and the recorded first reflected echo is used for comparison.
According to the second aspect of the present invention, it is not necessary to measure the first reflected echo, which is a reference for comparison, every time the measurement is performed, so that the time can be shortened. For example, when the first time is the start time without deposits and the second time is the elapsed time with deposits, the deposits are peeled off and the first reflected echo is measured at the elapsed time. You don't have to. In addition, by making the comparison standard constant, the detection accuracy of the change status including the adhesion status is improved.

According to the third aspect of the present invention, the first reflected echo intensity is measured as the first reflected echo, the second reflected echo intensity is measured as the second reflected echo, and the first reflected echo intensity and the integrated value are measured. It is characterized by using the temporal integrated value of the second reflected echo intensity.
According to the third aspect of the present invention, since the difference between the first reflected echo and the second reflected echo is clarified by using the reflected echo intensity that is easy to measure, the adhesion state of the deposit is included. The change status can be easily detected.

According to the fourth aspect of the present invention, the first power spectrum is measured as the first reflected echo and the second power spectrum is measured as the second reflected echo, and the first power spectrum and the second power spectrum are measured. It is characterized by using the change of the dominant frequency band for comparison.
According to the fourth aspect of the present invention, the difference between the first reflected echo and the second reflected echo is clarified by using the change in the frequency band of the power spectrum that reflects the change state including the adhesion state. Therefore, it becomes easy to detect the change status including the adhesion status of the deposits.

The present invention according to claim 5 is characterized in that the structure is a hull and the deposits are marine organisms that adhere to the hull.
According to the fifth aspect of the present invention, it is possible to detect a change state including an attachment state of marine organisms and the like adhering to the hull.

The present invention according to claim 6 is characterized in that ultrasonic waves are incident from the inside of the hull and the first reflected echo or the second reflected echo is measured inside.
According to the sixth aspect of the present invention, it is possible to detect a change state including an adhesion state of marine organisms from the inside of the hull even while sailing or berthing.

The present invention according to claim 7 is characterized in that the incident of ultrasonic waves and the measurement of the first reflected echo and the second reflected echo are performed at the same location in the structure.
According to the seventh aspect of the present invention, even if the time changes, the change state including the adhesion state of the deposits at the same place can be accurately detected.

The present invention according to claim 8 is characterized in that the incident of ultrasonic waves and the measurement of the first reflected echo and the second reflected echo are performed at different parts of the structure.
According to the eighth aspect of the present invention, it is possible to detect a change state including an adhesion state of deposits over a wide range.

The present invention according to claim 9 is characterized in that the incident of ultrasonic waves is performed at a plurality of locations of the structure, and the measurement of the first reflected echo and the second reflected echo is performed at one location of the structure.
According to the ninth aspect of the present invention, it is possible to detect a change state including an adhesion state of deposits over a wider range.

The present invention according to claim 10 is characterized in that the state of adhesion of the adhered matter to the detected structure is notified.
According to the tenth aspect of the present invention, it is possible to notify a person who is away from the detection site of the change status including the adhesion status.

In the surface change status detection system by ultrasonic waves corresponding to claim 11, the surface change status is detected by detecting the surface change status including the adhesion status of deposits to the structure using ultrasonic waves. In the system, at least the ultrasonic incident means for incidenting ultrasonic waves on the structure, at least the reflected echo measuring means for measuring the reflected echo from the structure, and the first reflected echo and the second reflected echo at the first time. Compare the integrated value or power spectrum of the second reflected echo at time , or change including the adhesion status of deposits to the structure based on the deviation of the waveforms of the first reflected echo and the second reflected echo. It is characterized by being provided with an adhesion detecting means for detecting a situation.
According to the eleventh aspect of the present invention, for comparison of the integrated value or the power spectrum of the first reflected echo and the second reflected echo, or the deviation of the waveforms of the first reflected echo and the second reflected echo. based on by detecting a change situation, including the adhesion state, one of a change situation, including the adhesion state of the deposit in the surface of the structure, for example, the other in relation one surface inextricably linked It can be detected from the surface side. As a result, for example, the change status including the presence or absence of deposits on the outer surface of the hull can be detected even from the inside of the hull, so that the deposits adhere to the outer surface of the hull regardless of whether it is moored or sailing. It will be possible to monitor the change situation including the situation in a timely manner.

The present invention according to claim 12 is characterized in that the present invention includes a recording means for recording the result of pre-measurement of the first reflected echo at the first time and using it for comparison with the second reflected echo. ..
According to the twelfth aspect of the present invention, it is not necessary to measure the first reflected echo as a reference for comparison every time the measurement is performed, so that the time required for the measurement can be shortened. In addition, by making the comparison standard constant, the detection accuracy of the change status including the adhesion status is improved.

According to the thirteenth aspect of the present invention, the reflected echo measuring means measures the first reflected echo intensity as the first reflected echo and the second reflected echo intensity as the second reflected echo, and the adhesion detecting means As an integrated value, the temporal integrated value of the first reflected echo intensity and the second reflected echo intensity is used for comparison.
According to the thirteenth aspect of the present invention, since the difference between the first reflected echo and the second reflected echo is clarified by using the reflected echo intensity that is easy to measure, the adhesion state of the deposit is included. The change status can be easily detected.

In the present invention according to claim 14, the reflected echo measuring means measures the first power spectrum as the first reflected echo and the second power spectrum as the second reflected echo, and the adhesion detecting means is the first. It is characterized in that the change of the dominant frequency band of the power spectrum of 1 and the power spectrum of the second is used for comparison.
According to the 14th aspect of the present invention, the difference between the first reflected echo and the second reflected echo is clarified by using the change in the frequency band of the power spectrum that reflects the change state including the adhesion state. Therefore, it becomes easy to detect the change status including the adhesion status of the deposits.

The present invention according to claim 15 is characterized in that the structure is a hull and the deposits are marine organisms that adhere to the hull.
According to the fifteenth aspect of the present invention, it is possible to detect a change state including an adhesion state of marine organisms and the like adhering to the hull.

The present invention according to claim 16 is characterized in that the ultrasonic incident means incidents ultrasonic waves on the hull from the inside of the hull, and the reflected echo measuring means measures the reflected echo inside.
According to the sixteenth aspect of the present invention, it is possible to detect a change state including an adhesion state of marine organisms and the like from the inside of the hull even while sailing or berthing.

The present invention according to claim 17 is characterized in that the incident of ultrasonic waves and the measurement of the first reflected echo and the second reflected echo are performed at the same location in the structure.
According to the 17th aspect of the present invention, even if the time changes, the change state including the adhesion state of the deposits at the same place can be detected.

The present invention according to claim 18 is characterized in that the ultrasonic wave incident means and the reflected echo measuring means are provided at different places in the structure, and the ultrasonic wave incident and the reflected echo are measured at different places.
According to the eighteenth aspect of the present invention, it is possible to detect a change state including an adhesion state of deposits over a wide range.

In the present invention according to claim 19, the ultrasonic wave incident means is provided at a plurality of places in the structure, the ultrasonic waves are incident at a plurality of places, the reflected echo measuring means is provided at one place in the structure, and the reflected echo is measured. Is characterized in that it is performed in one place.
According to the nineteenth aspect of the present invention, it is possible to detect a change state including an adhesion state of deposits over a wider range.

The present invention according to claim 20 is characterized by comprising a notifying means for notifying the state of adhering to a structure detected by the adhering detecting means.
According to the 20th aspect of the present invention, it is possible to notify a person who is away from the detection site of the change status including the adhesion status.

According to the method for detecting the change state of the surface by ultrasonic waves of the present invention, the integrated value or the power spectrum of the first reflected echo and the second reflected echo is compared, or the first reflected echo and the second reflected echo are compared. of by detecting a change situation, including the adhesion state on the basis of the deviation of the waveform, a change situation, including the adhesion state of the deposit on one surface of the structure, for example, one surface inextricably linked relationship It can be detected from the other side of the surface. As a result, for example, the change status including the presence or absence of deposits on the outer surface of the hull can be detected even from the inside of the hull, so that the deposits adhere to the outer surface of the hull regardless of whether it is moored or sailing. It will be possible to monitor the change situation including the situation in a timely manner.

Further, when the first reflected echo at the first time is measured and recorded in advance and the recorded first reflected echo is used for comparison, the first reflected echo as a reference for comparison is measured each time. Time can be shortened because there is no need to measure. For example, when the first time is the start time without deposits and the second time is the elapsed time with deposits, the deposits are peeled off and the first reflected echo is measured at the elapsed time. You don't have to. In addition, by making the comparison standard constant, the detection accuracy of the change status including the adhesion status is improved.

Further, the first reflected echo intensity is measured as the first reflected echo, the second reflected echo intensity is measured as the second reflected echo, and the integrated values of the first reflected echo intensity and the second reflected echo intensity are measured. When the temporal integrated value is used, the difference between the first reflected echo and the second reflected echo becomes clear by using the reflected echo intensity that is easy to measure, so the change including the adhesion status of the deposits is included. The situation can be easily detected.

Further, the first power spectrum is measured as the first reflected echo, and the second power spectrum is measured as the second reflected echo, and the change in the dominant frequency band of the first power spectrum and the second power spectrum is performed. Is used for comparison because the difference between the first reflected echo and the second reflected echo becomes clear by using the change in the frequency band of the power spectrum that reflects the change status including the adhesion status. It becomes easy to detect the change status including the adhesion status of the kimono.

Further, when the structure is a hull and the deposit is a marine organism that adheres to the hull, it is possible to detect the change status including the adhesion status of the marine organisms that adhere to the hull.

In addition, when ultrasonic waves are incident from the inside of the hull and the first reflected echo or the second reflected echo is measured inside, the adhesion status of marine organisms, etc. is included even while sailing or moored. The change status can be detected from the inside of the hull.

In addition, when the incident of ultrasonic waves and the measurement of the first reflected echo and the second reflected echo are performed at the same location of the structure, changes including the adhesion status of deposits at the same location even if the time changes. The situation can be detected.

Further, when the incident of ultrasonic waves and the measurement of the first reflected echo and the second reflected echo are performed at different locations in the structure, the change status including the adhesion status of deposits can be detected over a wide range. ..

Further, when the ultrasonic waves are incident at a plurality of places in the structure and the first reflected echo and the second reflected echo are measured at one place in the structure, the adhesion state of the deposits can be checked over a wider range. The change status including can be detected.

Further, when notifying the adhered state of the adhered matter to the detected structure, it is possible to inform the change status including the adhered state to a person who is away from the detection site.

Further, according to the ultrasonic deposit detection system of the present invention, the integrated value or power spectrum of the first reflected echo and the second reflected echo is compared, or the first reflected echo and the second reflected echo are compared. of by detecting a change situation, including the adhesion state on the basis of the deviation of the waveform, a change situation, including the adhesion state of the deposit on one surface of the structure, for example, one surface inextricably linked relationship It can be detected from the other side of the surface. As a result, for example, the change status including the presence or absence of deposits on the outer surface of the hull can be detected even from the inside of the hull, so that the deposits adhere to the outer surface of the hull regardless of whether it is moored or sailing. It will be possible to monitor the change situation including the situation in a timely manner.

Further, when a recording means for recording the result of pre-measurement of the first reflected echo at the first time and using it for comparison with the second reflected echo is provided, the first reflected echo serves as a reference for comparison. Since it is not necessary to measure the reflected echo every time the measurement is performed, the time required for the measurement can be shortened. In addition, by making the comparison standard constant, the detection accuracy of the change status including the adhesion status is improved.

Further, the reflected echo measuring means measures the first reflected echo intensity as the first reflected echo and the second reflected echo intensity as the second reflected echo, and the adhesion detecting means measures the first reflected echo as an integrated value. When the temporal integrated value of the reflected echo intensity and the second reflected echo intensity is used for comparison, the difference between the first reflected echo and the second reflected echo is clear by using the reflected echo intensity that is easy to measure. Therefore, it becomes easy to detect the change status including the adhesion status of the deposits.

Further, the reflected echo measuring means measures the first power spectrum as the first reflected echo and the second power spectrum as the second reflected echo, and the adhesion detecting means measures the first power spectrum and the second power spectrum. When the change in the dominant frequency band of the power spectrum of is used for comparison, the change in the frequency band of the power spectrum that reflects the change situation including the adhesion state is used for the first reflection echo and the second reflection. Since the difference from the echo becomes clear, it becomes easy to detect the change status including the adhesion status of the deposits.

Further, when the structure is a hull and the deposit is a marine organism that adheres to the hull, it is possible to detect the change status including the adhesion status of the marine organisms that adhere to the hull.

In addition, when the ultrasonic incident means incidents ultrasonic waves on the hull from the inside of the hull and the reflected echo measuring means measures the reflected echo inside, marine organisms and the like may be present even while sailing or moored. The change status including the adhesion status can be detected from the inside of the hull.

In addition, when the incident of ultrasonic waves and the measurement of the first reflected echo and the second reflected echo are performed at the same location of the structure, changes including the adhesion status of deposits at the same location even if the time changes. The situation can be detected.

Well, if the ultrasonic wave incident means and the reflected echo measuring means are provided at different places in the structure and the ultrasonic wave incident and the reflected echo are measured at different places, the adhesion status of the deposits can be measured over a wide range. The change status including can be detected.

Further, when the ultrasonic wave incident means is provided at a plurality of places in the structure, the ultrasonic waves are incident at a plurality of places, the reflected echo measuring means is provided at one place in the structure, and the reflected echo is measured at one place. Can detect change status including adhesion status of deposits over a wider range.

In addition, when a notification means for notifying the adhesion status of the deposit to the structure detected by the adhesion detection means is provided, the change status including the adhesion status is notified to a person who is away from the detection site. Can be done.

The figure which shows the arrangement example of the deposit detection system by ultrasonic wave in this embodiment. Schematic diagram of the equipment used in the experiment Diagram showing an example of reflected echo Conceptual diagram showing an example of ultrasonic reflection The figure which shows the example of the integrated value (cumulative value) of the reflected echo intensity. The figure which shows the example of the integral value of the reflected echo intensity at the time when the deviation between the 1st reflected echo and the 2nd reflected echo becomes substantially constant. The figure which shows the example of the power spectrum of the reflected echo The figure which shows the other arrangement example of the ultrasonic wave incident means and the reflected echo measuring means

The method for detecting deposits by ultrasonic waves and the system for detecting deposits by ultrasonic waves in the embodiment of the present invention will be described.
The method and detection system for detecting deposits by ultrasonic waves of the present embodiment emits ultrasonic waves and detects the state of adhesion of deposits to the structure by using the reflected echo reflected from the structure and the deposits. ..
The surface changes include foreign deposits, growth of deposits, precipitation from the surroundings, chemical changes in the structure, and the surface of the structure becoming deposits. Shall include.

FIG. 1 is a diagram showing an arrangement example of a deposit detection system by ultrasonic waves in the present embodiment.
In the structure 1, one surface 1A is in contact with the liquid and the other surface 1B is not in contact with the liquid. It is preferable to fill the space between the ultrasonic probe 10 and the other surface 1B with a contact medium (glycerin or the like) that promotes the transmission of ultrasonic waves. The structure 1 is, for example, a hull. If the liquid in contact with one surface (outer surface of the hull, etc.) 1A is seawater, marine organisms such as barnacles may adhere to one surface 1A. In addition to the hull skin, the "hull" includes sea chests, propellers, seawater cooling system components (pipes, heat exchangers, gratings, etc.), steering devices such as rudders, and parts submerged in seawater such as stabilizers. Etc. are included.
The detection system for deposits by ultrasonic waves includes an ultrasonic incident means 11 that emits ultrasonic waves, a reflected echo measuring means 12 that receives ultrasonic waves (reflected echoes) that are reflected by a reflecting surface and become echoes, and reflected echoes. Adhesion detecting means 21 for detecting the adhering state of the adhering matter to the structure 1 based on the above, recording means 22 for recording the reflected echo data, and notification of the adhering state of the detected adhering matter by sound or letters. Means 23 is provided.
In the present embodiment, one ultrasonic probe 10 for transmitting and receiving ultrasonic waves also serves as the ultrasonic incident means 11 and the reflected echo measuring means 12.
Further, the adhesion detecting means 21, the recording means 22, and the notifying means 23 are provided in one notebook computer 20.
A pulsar receiver 30 for transmitting and receiving ultrasonic signals and an oscilloscope 40 are arranged between the ultrasonic probe 10 and the notebook computer 20, and the pulsar receiver 30 and the oscilloscope 40 are arranged between the ultrasonic probe 10 and the pulsar receiver 30. The oscilloscope 40 and the notebook computer 20 are connected by wire. It is also possible to make a part or all of the wired connection a wireless connection.
The reflected echo signal measured by the ultrasonic probe 10 is taken into the notebook computer 20 via the oscilloscope 40. The incident means 11 and the reflected echo measuring means 12 of the ultrasonic probe 10, the adhesion detecting means 21 as a function of the notebook computer 20, the recording means 22, the notification means 23, the pulsar receiver 30, and the oscilloscope 40 are individually used as appropriate. It can also be combined and configured.

As shown in FIG. 1, the ultrasonic deposit detection system, including the ultrasonic incident means 11 and the reflected echo measuring means 12, is arranged on only one side of the structure 1.
In FIG. 1, the tip of the ultrasonic probe 10 (ultrasonic wave incident means 11 and reflected echo measuring means 12) is brought into contact with the other surface 1B of the wall of the structure 1, and the notebook computer 20, the pulsar receiver 30, and the oscilloscope 40 are brought into contact with each other. Is shown on the floor.

The deposits adhering to the structure 1 are detected by the following procedure.
First, for the structure 1, a measurement point is determined as a position for confirming the adhesion state of deposits such as marine organisms. For this measurement point, it is preferable to select a position where no deposits adhere to one surface 1A at that time.
Next, the tip of the ultrasonic probe 10 is brought into close contact with the other surface 1B of the structure 1 at the determined measurement location via glycerin or the like. Next, the ultrasonic wave incident means 11 transmits an ultrasonic wave toward the measurement point to make the ultrasonic wave incident on the structure 1, and the reflected echo is measured by the reflected echo measuring means 12. The reflected echo measured at this time is recorded in the recording means 22 as the first reflected echo at the first time.
After a predetermined time has elapsed from the measurement of the first reflected echo at the first time, the reflected echo is measured at the same position as the measurement point of the first reflected echo at the first time. First, the tip of the ultrasonic probe 10 is brought into close contact with the other surface 1B of the hull 1 at the measurement point. Next, the ultrasonic wave incident means 11 transmits an ultrasonic wave toward the measurement point to make the ultrasonic wave incident on the structure 1, and the reflected echo is measured by the reflected echo measuring means 12. The reflected echo measured at this time is recorded in the recording means 22 as the second reflected echo at the second time.

After measuring the second reflected echo at the second time, the adhesion detecting means 21 transfers the integrated value or power spectrum of the first reflected echo recorded in the recording means 22 and the integrated value of the second reflected echo. Or read the power spectrum and compare the two.
As a result of comparison, if there is no predetermined difference between the integrated value or power spectrum of the first reflected echo and the integrated value or power spectrum of the second reflected echo, it is between the first time and the second time. It is judged that the state of adhesion of the deposits on one surface 1A at the measurement point has not changed. If there is a predetermined difference between the integrated value or power spectrum of the first reflected echo and the integrated value or power spectrum of the second reflected echo, measurement is performed between the first time and the second time. It is determined that the state of adhesion of the deposit to one surface 1A at the location has changed.
The adhesion detection system by ultrasonic waves notifies the measurer, the manager, and the like of the detection result by the adhesion detection means 21 through the notification means 23 connected to the wired or wireless communication network. By providing the notification means 23, it is possible to notify the adhesion status to a person who is away from the detection site. It should be noted that the notification means 23 includes all means that can perform approximately notification such as image, voice, and tactile sensation.

Here, an experiment using the present invention will be described. FIG. 2 is a schematic view of the apparatus used in the experiment.
In this experiment, the structure was simulated with the test piece 2. The test piece 2 is made of general structural steel (SS400) and has dimensions of 200 mm in height, 190 mm in width, and 9 mm in thickness. The surface of the test piece 2, anticorrosive paint coating thickness 250μm is applied. The barnacles were attached only to one surface 2A by immersing the test piece 2 in seawater in the actual sea area for a long time. The size of the attached barnacle is about 10 mm in diameter at the portion in contact with the test piece 2.
Assuming measurement from the inside of the hull during navigation, one side 2A of the test piece 2 to which the barnacles are attached is in contact with the water surface, and the other side 2B to which the barnacles are not attached is super The measurement was performed by injecting a sound wave. Two measurement points for the test piece 2 were selected, the first measurement point was the position where the barnacles did not adhere to one surface 2A, and the second measurement point had the barnacles attached to one surface 2A. It was the position where it was.
First, at the first measurement point (without Fujitsubo adhesion), ultrasonic waves are transmitted from the ultrasonic incident means 11 with the tip of the ultrasonic probe 10 in close contact with the other surface 2B, and the ultrasonic waves are sent to the test piece 2. The incident was made, and the reflected echo was measured by the reflected echo measuring means 12. The reflected echo measured at this time was recorded in the recording means 22 as the first reflected echo at the first time.
Next, at the second measurement point (with Fujitsubo adhesion), the ultrasonic wave is transmitted from the ultrasonic wave incident means 11 with the tip of the ultrasonic probe 10 in close contact with the other surface 2B, and the ultrasonic wave is sent to the test piece. It was incident on 2 and the reflected echo was measured by the reflected echo measuring means 12. The reflected echo measured at this time was recorded in the recording means 22 as the second reflected echo at the second time.

FIG. 3 is a diagram showing the reflected echo in this experiment, in which the vertical axis represents voltage [mV] and the horizontal axis represents time [nsec]. In FIG. 3A, the voltage is represented by a positive or negative value, and in FIG. 3B, the voltage is represented by an absolute value. In FIG. 3, the broken line shows the measurement result at the first measurement point (without barnacles attached), and the solid line shows the measurement result at the second measurement point (with barnacles attached).
Further, FIG. 4 is a conceptual diagram showing the reflection of ultrasonic waves in this experiment. FIG. 4A shows the reflection at the second measurement point (with barnacles attached), and FIG. 4B shows the reflection at the first measurement point (without barnacles attached).
From FIG. 3, it can be seen that the waveforms of the two waveforms deviate after a certain period of time has elapsed from the start of the measurement (at a position separated from the ultrasonic probe 10 by a certain distance). This deviation is due to the difference in the number of reflecting surfaces between the two. As shown in FIG. 4A, in the case of the second measurement point (with barnacles attached), the reflection surface of the ultrasonic waves incident on the test piece 2 is the boundary surface between the test piece 2 and the anticorrosion paint 3. There are a total of three, the interface between the anticorrosive paint 3 and the barnacle 4, and the interface between the barnacle 4 and the seawater 5. On the other hand, as shown in FIG. 4B, in the case of the first measurement point (without barnacle adhesion), the reflection surface of the ultrasonic wave incident on the test piece 2 is the boundary between the test piece 2 and the anticorrosion paint 3. There are a total of two surfaces, the surface and the interface between the anticorrosive paint 3 and the seawater 5. That is, since the second measurement point (with barnacles attached) has more reflecting surfaces than the first measurement point (without barnacles attached), there are more reflected echoes, and the waveforms of the two are out of alignment.

When there are deposits in this way, the interface (reflecting surface) that reflects ultrasonic waves increases, so more reflected echoes are returned. Therefore, as the first reflected echo at the first measurement point (without Fujitsubo adhesion), the temporal integrated value of the first reflected echo intensity and the second reflection at the second measurement point (with Fujitsubo adhesion) By comparing the second reflected echo intensity with the temporal integrated value as an echo, the difference between the first reflected echo and the second reflected echo becomes clear using the reflected echo intensity that is easy to measure. The presence or absence of deposits can be easily detected.
FIG. 5 is a diagram showing an integrated value (cumulative value) of the reflected echo, in which the vertical axis represents voltage [mV] and the horizontal axis represents time [nsec]. In FIG. 5, the broken line shows the measurement result at the first measurement point (without barnacles attached), and the solid line shows the measurement result at the second measurement point (with barnacles attached).
FIG. 6 is a diagram showing an integrated value [μV · s] of the reflected echo at the time when the deviation between the first reflected echo and the second reflected echo becomes substantially constant. In FIG. 6, the data on the left side shows the measurement result at the first measurement point (without barnacles attached), and the data on the right side shows the measurement result at the second measurement point (with barnacles attached).
From FIGS. 5 and 6, it can be seen that the integrated value of the reflected echo intensity at the second measurement point (with barnacles attached) is larger than that at the first measurement point (without barnacles attached).
Note that FIG. 5 shows the temporal transition of the integrated value (cumulative value) of the reflected echo, and FIG. 6 shows the difference between the accumulated values at a certain time in FIG. 5 as the integrated value. By seeing the difference, it is possible to judge the presence or absence of adhesion. The determination of adhesion based on the integrated value is made not only by the difference in the integrated values, but also in the state before the cumulative value (integrated value) and the difference become substantially constant, for example, in the two curves of FIG. Judgment is also possible from the transition of the difference (slope, differentiation, etc.). At this time, comparison can be performed using visual inspection, pattern recognition, image processing, artificial intelligence (AI), and the like.

Further, FIG. 7 is a diagram showing a power spectrum of the reflected echo, in which the vertical axis represents the power spectrum and the horizontal axis represents the frequency [MHz].
The data shown in FIG. 7 is obtained by frequency-converting the data shown in FIG. 3 by Fourier transform. In FIG. 7, the measurement result at the first measurement point (without barnacles attached) is shown by a broken line, and the measurement result at the second measurement point (with barnacles attached) is shown by a solid line.
From FIG. 7, it can be seen that there is a significant difference in the degree of change in the frequency bands of the two power spectra.
In this way, since the degree of change in the frequency band of the power spectrum differs between the case where the deposit is attached and the case where the deposit is not attached, the first power spectrum is measured as the first reflected echo. By measuring the second power spectrum as the second reflected echo and using the change in the dominant frequency band of both power spectra for comparison, the change in the frequency band of the power spectrum that reflects the adhesion situation is used. The difference between the first reflected echo and the second reflected echo becomes clear, and the presence or absence of deposits can be easily detected.
Comparison of dominant frequency band changes can be made using visual inspection, pattern recognition, image processing, artificial intelligence (AI), and the like.
It is also possible to integrate and compare the first power spectrum and the second power spectrum.

According to the above experiment, there is a difference in the integrated value or power spectrum of the reflected echo between the case where the Fujitsubo is attached and the case where the Fujitsubo is not attached. By comparing at least one of them, it can be seen that the state of adhesion of the deposit, such as the presence or absence of the deposit, can be detected.
Therefore, as described with reference to FIG. 1, the ultrasonic waves are incident on the structure 1 at the first time to measure the first reflected echo, and the ultrasonic waves are incident on at least the structure 1 at the second time. By measuring the second reflected echo and comparing the integrated value or power spectrum of the first reflected echo with the second reflected echo to detect the adhesion state of the deposit to the structure 1, the structure 1 The state of adhesion of deposits on one surface 1A can be detected, for example, from the side of the other surface 1B, which has a front-to-back relationship with one surface 1A. As a result, for example, the presence or absence of deposits on the outer surface of the hull can be detected even from the inside of the hull, so that the status of deposits on the outer surface of the hull can be monitored in a timely manner regardless of whether the ship is moored or sailing. This makes it possible to carry out efficient maintenance and management of the hull. In addition, for ships with long berthing intervals, the detection result of the adhesion status can be used to determine whether or not it is necessary to advance the docking time. In addition, from the perspective of cross-border biological issues, it is expected that checks on the status of biofouling on the hull when ocean-going vessels enter the port will become stricter, and this is expected to be used as a countermeasure. Regarding the integrated value of the reflected echo and the power spectrum, it is also possible to detect the adhesion state of the deposit by combining both.

In a state where no deposits are attached to the structure 1 such as during new shipbuilding or maintenance, the first reflected echo at the first time is measured in advance for each structure 1 and recorded in the recording means 22. It is preferable to keep it.
By recording the first reflected echo as a reference for comparison in advance, it is not necessary to measure the first reflected echo each time the measurement is performed, so that the time required for the measurement can be shortened. For example, when the first time is the start time without deposits and the second time is the elapsed time with deposits, the deposits are peeled off and the first reflected echo is measured at the elapsed time. You don't have to. Further, when the comparison standard becomes constant, the accuracy of detecting the adhesion state by the adhesion detection means 21 is improved. Further, by recording the reflected echo in the state where no deposit is attached to the structure 1 as the first reflected echo, the data of the reflected echo in the state where there is no deposit is clarified, and the presence or absence of the deposit is present. The detection accuracy can be further improved.

Further, the ultrasonic wave incident means 11 and the reflected echo measuring means 12 may change their relative positions and numbers according to the type and measurement range of the structure 1. Also in this case, the ultrasonic wave incident means 11 and the reflected echo measuring means 12 are arranged only on one side of the structure 1.
FIG. 8 is a diagram showing another arrangement example of the ultrasonic wave incident means and the reflected echo measuring means. In FIG. 8, the left side is a bottom view in which the structure is omitted, and the right side is a side sectional view.
In FIG. 8A, the ultrasonic wave incident means 11 and the reflected echo measuring means 12 are housed in one housing, and as in FIG. 1, the ultrasonic wave incident, the first reflected echo, and the second reflected echo Is measured at the same location in the structure 1. By arranging in this way, it is possible to accurately detect the adhesion state of deposits at the same location even if the time changes. In FIG. 1, the ultrasonic wave incident means 11 also serves as the reflected echo measuring means 12, but in FIG. 8A, the ultrasonic wave incident means 11 and the reflected echo measuring means 12 are independent. ..
In FIG. 8B, the ultrasonic wave incident means 11 and the reflected echo measuring means 12 are provided separately, and the ultrasonic wave incident and the reflected echo are measured at different locations. By arranging in this way, it is possible to detect the adhesion state of deposits over a wider range.
In FIG. 8C, ultrasonic wave incident means 11 are provided at a plurality of locations of the structure 1, reflection echo measuring means 12 is provided at one location of the structure 1, ultrasonic waves are incident at a plurality of locations, and reflection echoes are performed. Is measured at one place. By arranging in this way, it is possible to detect the adhesion state of deposits over a wider range.
As the ultrasonic wave transmitted from the ultrasonic wave incident means 11, a longitudinal wave, a transverse wave, or a surface wave is selected according to the arrangement and measurement range of the ultrasonic wave incident means 11 and the reflected echo measuring means 12.

Further, the structure 1 is not limited to the above-mentioned hull.
The structure 1 may be a grating installed in the piping of a power plant or factory on land, piping equipment, or an intake of seawater for cooling.
Further, the structure 1 can be a facility / equipment such as wind power generation, wave power generation, marine current power generation, tidal current power generation, water current power generation, or drilling equipment for oil / minerals at sea or underwater.
The structure 1 can also be a sea mark, a buoy, an aviation / port facility, a barnacle aquaculture facility, or the like.

It is also possible to detect the state of adhesion of deposits by measuring the incident of ultrasonic waves and the reflected echo thereof from the outside of the structure 1. For example, when the structure 1 is a hull, ultrasonic waves are emitted from the outside (adhesion side) to the hull skin, etc. by means of a deposit detection system mounted on an ROV, AUV (autonomous underwater vehicle), etc. Alternatively, it is incident through water and its reflected echo is measured on the outside.

According to the present invention, the state of change in the surface including the presence or absence of deposits on the outer surface of the hull can be detected even from the inside of the hull, so that the surface is attached to the outer surface of the hull regardless of whether it is moored or sailing. It is possible to timely monitor changes in the surface, including the adhesion of kimono, and to efficiently maintain and manage the outer surface of the hull. It can also help solve the problem of cross-border living organisms by ocean-going vessels. Furthermore, it is possible to detect the state of adhesion of various deposits to various structures , changes in the coating film thickness of the surface due to physical sea erosion or wear, and the like.

1 Structure 11 Ultrasonic wave incident means 12 Reflected echo measuring means 21 Adhesion detecting means 22 Recording means 23 Notifying means

Claims (20)

It is a method of detecting a surface change state including a state of adhesion of deposits to a structure using ultrasonic waves, and is a method of detecting a surface change state in which the ultrasonic waves are incident on the structure at a first time. The first reflected echo is measured, the ultrasonic wave is incident on at least the structure at the second time, the second reflected echo is measured, and the integrated value of the first reflected echo and the second reflected echo. Alternatively, the power spectra can be compared , or a change status including the adhesion status of the deposit to the structure can be detected based on the deviation between the waveforms of the first reflected echo and the second reflected echo. A characteristic method for detecting changes in the surface by ultrasonic waves. The change in surface due to ultrasonic waves according to claim 1, wherein the first reflected echo at the first time is measured and recorded in advance, and the recorded first reflected echo is used for the comparison. How to detect the situation. The first reflected echo intensity is measured as the first reflected echo, and the second reflected echo intensity is measured as the second reflected echo, and the first reflected echo intensity and the second reflection are measured as the integrated values. The method for detecting a surface change state by ultrasonic waves according to claim 1 or 2, wherein a temporal integrated value of echo intensity is used. The first power spectrum is measured as the first reflected echo, and the second power spectrum is measured as the second reflected echo, and the dominant frequency band of the first power spectrum and the second power spectrum is measured. The method for detecting a surface change state by ultrasonic waves according to claim 1, wherein the change in the above is used for the comparison. The detection of a surface change state by ultrasonic waves according to any one of claims 1 to 4, wherein the structure is a hull and the deposits are marine organisms adhering to the hull. Method. The state of surface change due to ultrasonic waves according to claim 5, wherein the ultrasonic waves are incident from the inside of the hull, and the first reflected echo or the second reflected echo is measured inside the hull. Detection method. The invention according to any one of claims 1 to 6, wherein the incident of the ultrasonic wave and the measurement of the first reflected echo and the second reflected echo are performed at the same location of the structure. How to detect the change of the surface by ultrasonic waves. The invention according to any one of claims 1 to 6, wherein the incident of the ultrasonic wave and the measurement of the first reflected echo and the second reflected echo are performed at another location of the structure. The method for detecting changes in the surface by ultrasonic waves described above. Claims 1 to 1, wherein the ultrasonic waves are incident at a plurality of locations of the structure, and the first reflected echo and the second reflected echo are measured at one location of the structure. The method for detecting a change state of a surface by ultrasonic waves according to any one of 6. The method for detecting a surface change state by ultrasonic waves according to any one of claims 1 to 9, wherein the state of attachment of the deposit to the detected structure is notified. A surface change status detection system that detects the surface change status including the adhesion status of deposits to the structure using ultrasonic waves, and is an ultrasonic incident means for at least incidenting the ultrasonic waves on the structure. And at least compare the reflected echo measuring means for measuring the reflected echo from the structure with the integrated value or power spectrum of the first reflected echo at the first time and the second reflected echo at the second time. Alternatively, it is provided with an adhesion detecting means for detecting a change state including the adhesion state of the deposit to the structure based on the deviation of the waveforms of the first reflected echo and the second reflected echo. A featured ultrasonic surface change detection system. The eleventh aspect of claim 11, wherein the result of pre-measurement of the first reflected echo at the first time is recorded, and a recording means for using the recording means for comparison with the second reflected echo is provided. A system for detecting surface changes caused by ultrasonic waves. The reflected echo measuring means, the first echo intensity as the first echo and said second second echo intensity is measured as a reflected echo, the deposition detecting unit, as the integral value The detection of a surface change state by ultrasonic waves according to claim 11 or 12, wherein the temporal integrated value of the first reflected echo intensity and the second reflected echo intensity is used for the comparison. system. The reflected echo measuring means measures the first power spectrum as the first reflected echo and the second power spectrum as the second reflected echo, and the adhesion detecting means measures the first power spectrum. The ultrasonic surface change state detection system according to claim 11 or 12, wherein the change in the dominant frequency band of the second power spectrum is used for the comparison. The detection of a surface change state by ultrasonic waves according to any one of claims 11 to 14, wherein the structure is a hull and the deposits are marine organisms adhering to the hull. system. The super-ultrasonic wave according to claim 15, wherein the ultrasonic wave incident means incidents the ultrasonic wave into the hull from the inside of the hull, and the reflected echo measuring means measures the reflected echo inside the hull. A detection system for surface changes caused by ultrasonic waves. The method according to any one of claims 11 to 16, wherein the incident of the ultrasonic wave and the measurement of the first reflected echo and the second reflected echo are performed at the same location of the structure. A system for detecting surface changes caused by ultrasonic waves. The eleventh aspect of claim 11, wherein the ultrasonic wave incident means and the reflected echo measuring means are provided at different places in the structure, and the incident of the ultrasonic waves and the measurement of the reflected echo are performed at different places. Item 4. The system for detecting a surface change state by ultrasonic waves according to any one of Items 16. The ultrasonic wave incident means is provided at a plurality of locations of the structure, the ultrasonic waves are incident at a plurality of locations, the reflected echo measuring means is provided at one location of the structure, and the reflected echo is measured at one location. The system for detecting a surface change state by ultrasonic waves according to any one of claims 11 to 16, wherein the system is characterized by the above-mentioned method. The surface by ultrasonic waves according to any one of claims 11 to 19, wherein the notification means for notifying the adhesion status of the deposit to the structure detected by the adhesion detecting means is provided. Change status detection system.