FR2602359A1 - METHOD AND APPARATUS FOR MEASURING A DETECTION OF FENDERS USING AN EMBARCADER SONAR SYSTEM - Google Patents

Abstract

THE PRESENT INVENTION CONCERNS A METHOD AND DEVICE FOR MEASURING A DEFORMATION OF FENDERS. THE DEVICE IS CHARACTERIZED IN THAT IT INCLUDES A MEANS OF CALCULATING A NORMALIZED DISTANCE 30, A MEANS OF JUDGMENT 40 AND A MEANS OF PRODUCTION OF DEFORMATION DATA 50. THE PRESENT INVENTION FOUND APPLICATION IN THE MARINE FIELD.

Description

The present invention relates to a method and a device for measuring

  deforming fenders using a docking station sonar system to measure, for example, a distance of a ship from a wharf, a dike or jetty, etc., or a speed of movement of the ship when this one is being wet or moored at the pier. A location where the ship is wet or at the pier is generally as illustrated in Figure 5. In the mooring or landing area 2, a mooring position along a line of a bow and dash. 'a

  stern of the ship 1 is called a normal mooring 6.

  The mooring or landing site 2 may, in general, be a wharf, a wharf, a dike or jetty, a mooring or the like. The mooring or landing site 2 is usually equipped with fenders made of an elastic material such as synthetic rubber, to cushion the impacts caused by the collision at the time of collision with the ship or to protect various equipment provided around anchorage site 2

or landing stage.

  The mooring or boarding operation must be safe and fast. Safety is crucial, especially in the anchorage or docking of a large ship such as a tanker or a very large carrier that carries flammable material such as oil, liquefied petroleum gas or liquefied natural gas. because the slightest mistake of maneuver or judgment could lead to a serious accident. If the speed of the vessel approaching the berth or the distance from the vessel 30 of the wharf or dyke or jetty to which the vessel is being moored is falsely estimated, the vessel may collide with the wharf or jetty, which may cause stress or damage to the body of the ship due to the impact of the collision. In the most serious case, there could be a danger of ignition of flammable gases or oil carried

  on the ship. Thus, a fatal accident can be caused.

  To prevent such an accident, expensive fenders 3 are provided in the mooring or landing location 2 at positions corresponding to the bow and the stern of the ship to dampen the shock by the collision. In addition, an ultrasonic dock sonar system to inform a vessel speed or distance from the vessel to the wharf

  or jetty is provided so that the vessel can be wetted more accurately and more securely at location 2.

  The docking station sonar system generally includes transceiver transducers 5-1, 5-2 which are installed at positions corresponding to the bow and stern of the vessel to be wetted, as shown in Figures 5 and 6. The large tanker or bulk material carrier - as described above is usually wet at a similar position at the same wetting or docking location, so that the receiving transceiver transducers can be fixedly installed at such positions. . The dockside sonar system measures the distance and speed of the vessel that is docking at the mooring or landing location. The system further includes a large display (not shown) such as an electrically illuminated digital scoreboard which is provided on the wharf or jetty and visible at a distance of up to 100 or 200 m.

the wharf or jetty.

  In the pier landing sonar system, a main or central measuring unit is installed on the pier or jetty and the transceiver transducers 5-1, 5-2 are immersed to horizontally transmit ultrasonic waves from the location. 2 mooring or landing stage

  to the ship 1 and receive the wave reflected by the ship 1.

  This type of docked ultrasonic sonar system as arranged above operates as follows: First, an electrical signal generated from the central measurement unit 4 is applied across a signal line to the transceiver transducers. -1, 5-2 which are immersed at the mooring or landing site -5 at the positions corresponding to the bow and stern of the ship, respectively. The electrical signal applied to the transceiver transducers is then converted to an ultrasonic signal and the ultrasonic signal

  narrow beam is transmitted in the water to the ship 1.

  The ultrasonic beam is partially reflected by the ship's body 1. The reflected wave of the ship 1 returns to the transmitting transmitters 5-1, 5-2 and is converted into an electrical signal and returned back to the central measurement unit 4. The elapsed time of transmission of the ultrasonic signal of the transceiver transducers -1, 5-2 upon receipt of the reflection signal is proportional to the distance between the transceiver transducers 5-1, 5-2 and the ship 1 Thus, the elapsed time can be measured to obtain the distances from the bow and stern to the wharf or jetty 2. In addition, changes in such distances per unit of time can be measured to know the traveling speed. from the vessel to the mooring or landing site. These results

  The measurements are numerically indicated on the large display board (not shown) on the wharf or jetty.

  With such an indication, a pilot may maneuver the ship so that it can approach the wharf or jetty in parallel with it at a

suitable speed.

  In fact, however, it is sometimes quite difficult to dock or dock the vessel precisely at the anchor or landing position even if the pilot knows the distance and speed of the ship. This difficulty is often due to an inertia

  ship or influence of waves, tide or wind.

  This often causes the ship to collide against the fenders 3 when wet. Fenders 3 are shock absorbers or buffers to absorb collision shock and operate to absorb the kinetic energy of the ship to prevent the vessel from colliding with

the wharf or jetty.

  When a shock is applied to the fenders 3, a

  stress or tension is caused by an internal load.

  The constraint remains in the fenders 3 when the shocks have been applied repeatedly. This tires the material of the fenders 3, possibly leading to the breakage of the fenders after being subjected to repetitive shocks. Even in the case where the load application does not occur so frequently, if an extraordinarily large stress is caused at one time, the stress remains in the fenders, fatiguing the materials and eventually leading to breakage of the barriers. threshing later. In addition, when parquets 3 no longer work, they can not function as dampers and can not prevent the vessel from colliding with the wharf or jetty. Collision shock can cause stresses in the body of the ship and damage it. In an extreme case, it can

  There is a danger that the flammable gases or the oil in the ship will ignite.

  Also, even after completion of the boarding operation, the ship is oscillating due to the influence of waves, tides, etc., and the ship continues to collide. Against fenders 3. These collisions again cause a constraint in the fenders 3, which can be accumulated to a dangerous level such as

this can be the case.

  To avoid a serious accident as described above, it is necessary to replace the fenders with new fenders before they are broken. For this purpose, the state of the stress or charge accumulated in the fenders 3 must be detected. Fatigue detection in the fenders 3 can be performed by detecting the hysteresis of displacement of the apex ends of the fenders 3 or deformation of the fenders 3 due to compression and / or deformation of the fenders. More specifically, the amount of displacement or amount of deformation of the fenders 3 may be recorded to determine the amount of fatigue or stress remaining.

in the fenders.

  The recording of the displacement or deformation of the fender will also be useful for knowing the magnitude of the load applied to the fenders or the prior state of effort in the fenders when they break and

  to clear up the cause of the break.

  However, special equipment is needed to record the detected data and obtaining such equiments entails considerable costs. For this reason, the recording equipment does not have

  were made in conventional landing dock sonar systems.

  Accordingly, an object of the present invention is to provide a method for measuring the displacement or deformation of fenders, which is capable of easily detecting an amount of displacement or deformation of a fender using measurement data. an existing jetty sonar system, without providing for

special equipment.

  It is another embodiment of the present invention to provide a device for the implementation

  of the process as described above.

  The present invention provides a method for measuring fender deformation using a docking station sonar system in which a distance and a speed of movement of a ship are measured on the basis of a time elapsed for a one-way trip. return of ultrasonic waves which are transmitted from at least one immersed transmitter-receiver transducer to a wetting or landing site and received by it as reflection waves of the ship, which method is characterized in that it consists in: calculating a normalized distance between a reference position, which is set at a predetermined distance from the transceiver transducer, and the ship based on a distance between said transceiver transducer and the ship and a distance between the transceiver transducer and the reference position; producing the normalized distance as the ship's displacement data after it has reached said reference position or a preset position near the reference position; and get an amount of displacement from one end

  apex of the fender from the displacement data.

  The present invention also relates to a device for measuring a deflection of fenders in an ultrasonic docking system comprising at least one transceiver transducer installed at a mooring or landing site for a vessel for transmitting and receiving ultrasonic waves. and a central measurement unit for measuring a distance from the ship to the transceiver transducer and a vessel traveling speed based on an elapsed time of the ultrasonic waves transmitted and received by said transducer, which device is characterized in that it comprises: a normalized distance calculating means for calculating a normalized distance between a reference position, which is set at a predetermined distance from the transceiver transducer, and the ship based on a distance between the ship transceiver transducer and a distance between the emitter-receptive transducer eur and the reference position; judgment means for judging whether the ship has reached the reference position or a preset position near the reference position; and means for producing a displacement data for producing the normalized distance as a ship-moving datum when the judging means judges that the ship has reached the reference position or the nearby region established preliminarily; thus the deformation of the fenders is detected

  based on the displacement data.

  In the present invention, preferably, when the distance of the transceiver transducers to the ship is equal to or less than the distance of the transceiver transducers at the reference position, the displacement data as specified above is used as the displacement of the apex end of the fenders

  to measure the deformation of these.

  The reference position, however, may be established at a position closer to the landing or jetty than at the apex end position and a region between this reference position and the apex end of the fender.

  can be established previously as a close region.

  Alternatively, the reference position can be established at a position farther from the wharf or jetty than

  the aforementioned apex end position.

  Deformation of the fenders is achieved as a displacement amount of the apex end of the bumper and may be indicated by display or recorded by a recording device such as a printer. A limit value of the amount of strain that is determined at design time can be established so that it is possible to judge whether the

  measured displacement reaches the established strain limit.

  When the measured value reaches the set value, an alarm can be issued. On the other hand, if an accumulation of the amount of deformation reaches a pre-established precautionary value, an alarm can be emitted. The measure of the amount of deformation of the parebattages is based on the measurement of the displacement of the ship because the deformation of the parebattages is caused only by depression by the ship. For this, the measurement data by the docking sonar system is used in the present invention. More specifically, the reference position is set at a predetermined distance from the transceiver transducers and a distance from these transceiver transducers to the ship is normalized at a distance from the reference position. This normalized distance represents the vessel's displacement from the reference position. The displacement of the apex end of the fender and consequently the deformation of the fender are obtained on the basis of the vessel displacement data. The normalized distance is calculated based on the distance between the transceiver transducer and the ship and the distance between the transceiver transducer and the reference position, and in general the normalized distance is obtained by subtracting the last distance from the first. When the vessel is out of the reference position, the sign of the normalized distance is positive and when the ship is within the reference position, the sign of the

Normalized distance is negative.

  Detection of apex end displacement of the fenders or deformation of the fenders starts when the ship has entered the reference position or the previously established close region and the normalized distance is calculated as described above and then produced as displacement or deformation data. In this regard, the reference position can be set to any of the various positions as described above but, in general, it is set to a position corresponding to the apex end of the fender That the vessel has reached the reference position or not can be judged from the fact that the standardized distance has changed sign

positive to zero.

  When the reference position is set at the apex end position of the fender the negative value of the normalized distance represents the amount of displacement or amount of deflection deformation after the normalized distance has changed from zero to a negative value. In this case, therefore, the normalized distance record can be used as a record of a deformation or parcel displacement change. In the case where the reference position is set to a position within the the apex end position of the fender or closer to the jetty or pier 20 than the apex end position of the fender and the region between this reference position and the apex end position of the fender is previously established as a close region, the reference position may preferably be set at a position where the parebattage 25 has been placed or deformed at its maximum extension in an elastic limit which is determined according to the design of the fender. If such a position is chosen as the reference position, the displacement or deformation which barely leaves the stress in the fender 30 can be omitted from the measurement of the deformation or the displacement of the deflection. When the reference position is established at a distance of outside position at the end apex end of the parse or farther from the wharf or jetty than the apex end position of the parging the movement of the vessel before colliding with the parse can be recorded as the displacement data of the ship. If necessary, a change in the amount of motion and / or kinetic energy of the ship before and after the collision can be detected based on the recorded displacement data. So, the record can produce more detailed data

damage to the fender.

  As described above, the measurement data of the landing gear sonar system can effectively be used to easily detect the deformation of fenders.

  without using special equipment for this purpose.

  The invention will be better understood, and other purposes, features, details and advantages thereof

  will be more clearly apparent from the following explanatory description made with reference to the drawings

  attached diagrams given by way of example only, illustrating an embodiment of the invention, and in which: FIG. 1 is a block diagram showing an embodiment of the present invention; Fig. 2A is a plan view showing the arrangement of a landing pier sonar system usable in the embodiment; Fig. 2B is a side view of the docking station sonar system arrangement shown in Fig. 2A; Fig. 3A is a block diagram of a concrete circuit arrangement for operating the embodiment; FIG. 3B is a block diagram of a receiver provided in a central measurement unit for use in the present embodiment; Fig. 3C is a block diagram of a signal processing circuit provided in the central measurement unit for use in the present embodiment; Fig. 4 is a flowchart showing an operation of the embodiment; Fig. 5 is a plan view showing an arrangement of a conventional ultrasonic sonar system; and - Figure 6 is a side view of the arrangement

  of the conventional ultrasonic sonar system of FIG.

  A preferred embodiment of the method and the device

  Fenders deformation measurement using a docking sonar system will now be described.

  The arrangement of the ultrasonic docking sonar system used in the present embodiment will now be

  - described with reference to Figures 2A and 2B.

  The fender means 3 made of an elastic material such as a synthetic rubber are installed in a wetting or landing area 2 (referred to as "wetting location" in this embodiment) in which the ultrasonic sonar system dock

  usable in the present embodiment is installed.

  The ultrasonic docking sonar system comprises transceiver transducers 5-1 and 5-2 which are immersed at positions corresponding to the two docking positions of a bow and a stern of the ship 1 to be anchored, respectively and a central measurement unit 4 provided at a

  suitable position in the anchorage 2.

  A device for measuring deflection deformation according to the present invention comprises, as illustrated in FIG. 1, the landing gear sonar system comprising the transceiver transducers 5 and the main measurement unit 4 and a standardized distance calculating means 30, judgment means 40 and deformation data generating means 50, which are incorporated in the docking station sonar system. The normalized distance calculating means 30, the judging means 40 and the deformation data generating or output means 50 are implemented by a microcomputer 14 in the present embodiment as it

  will be described in detail later.

  For calculating the normalized distance, a reference position 7 is set at a predetermined distance from the transceiver transducers 5-1, 5-2. The normalized distance calculating means 30 calculates the normalized distance D between the reference position 7 and the ship 1 from a distance L between the receiving transceiver transducers 5-1, 5-2 and the ship 1 and a distance A between the transceiver transducers 5-1, 5-2 and the reference position 7. The calculation is performed according to the following formula:

D = L - A

  The reference position 7 is set so that it can coincide with a normal mooring 6 in the present embodiment. As a result, the reference position 7 is established in order to coincide with

  positions of the apex ends of the fenders 3.

  The judging means 40 judges whether the ship 1 has reached the reference position or not. In other words, it determines whether D 0 or not. If D is 0 or less than zero, judgment means 40 applies a judgment signal representative of D <0 to the production means of

deformation data 50.

  In response to the judgment signal, the deformation data generating means 50 produces the calculated normalized distance D as deformation or displacement information. More specifically, the normalized distance D (D <0) is transmitted as deformation data. This embodiment also includes a printer such as

  output means as will be described in detail later.

  The deformation data is transmitted or output by the printer 21.

  The deformation measuring device according to the present embodiment and the main measuring unit 4 of the landing gear sonar system used in the device

  are illustrated more specifically in Figure 3A.

  In FIG. 3A, the central measurement unit 4 comprises a circuit for producing a delay signal 9 for producing a transmission delay signal for the ultrasonic pulses and a switching signal for the transceiver transducers 5-1. 52; a blower circuit 10 responsive to the transmission timing signal for generating pulses of the drive current to produce the ultrasonic pulses; a selector 11 for switching the transceiver transducer 5-1 for the bow and the transceiver transducer 5-2 for the stern; a receiver 12 for receiving reflected signal input waves from the transceiver transmitters 5-1, 5-2; a signal processing circuit 13 for processing the received signals to measure an elapsed time of the round trip ultrasonic pulse; a microcomputer 14; a driver circuit 20; a

  printer 21; and a display device 22.

  The selector 11 serves to switch the operation between the bow and stern transceiver transducers and includes for example a mercury relay. A switch instruction is applied from the production circuit

timing signal 9.

  The receiver 12 includes a limiter 12a for protecting a rear-stage amplifier 12b from a high-voltage signal of the blower circuit 10 of the amplifier 12b, and a detector 12c. When there is a difference in sensitivity between the two transceiver transducers, the amplifier 12b may have two amplifying systems having different degrees of amplification to correct or compensate for the difference. These two amplifier systems

  can be switched synchronously with selector 11.

  The signal processing circuit 13 comprises a comparator 13a for pulsing the input signal, a pulse width discrimination circuit 13b capable of discriminating whether the pulse 35 is of a predetermined width or more for eliminating pulses of wider width. low, a gate control circuit 13c for establishing a timing width based on the timing signal of the timing signal generating circuit 9 and the pulse discriminated as being of the predetermined width or more, and a counter 13d which counts clock pulses while the door is open by the width or synchronization time as established above. The signal processing circuit 13 further comprises a noise level determining circuit for determining a noise included in the received signal, an echo level determining circuit for determining an echo level of the received signal, and a circuit for producing a status signal for producing a status signal of the determination results, which circuits are not shown in the figures. The status signal - is sent to the microcomputer 14 together with a value of

counter count 13d.

  The microcomputer 14 calculates the elapsed time of the ultrasonic pulses transmitted reciprocally from the count value of the counter 13d. The microcomputer 14 also has functions for calculating the distance between the transceiver transducers 5-1, 5-2 and the ship 1 and a speed

  of the ship based on distance changes in time.

  It also functions as the normalized distance calculating means 30, the judgment means 40 and the deformation data generating means 50 in the present embodiment. The microcomputer 14 comprises an input / output circuit 15, a central processing unit (hereinafter referred to as a CPU) 16, a read only memory (ROM) 17, a random access memory (RAM) 18, and a clock generator 19 for producing a clock pulse which is used as a reference for the calculation. The signal processing circuit 13 and the display 22 are connected to the input / output circuit 15. The printer 21 for recording the data is connected to the CPU 16 through the driver 20 which produces

  data such as distance and speed of movement.

  The ROM 17 has in memory an operation control program for the CPU 16 and the data A representative of the set position of the reference position 7 together with fixed data such as the switching data for switching the measured distance units. between "m" and "cm". The RAM 18 stores a program operation parameter for calculating the elapsed time of the forward and backward ultrasonic pulses from the count value of the counter 13d, a program operation parameter for calculating the distance L of the elapsed time and the speed of sound, and a program operation parameter for calculating the rate of change over time. It also stores a program operation parameter for calculating the normalized distance D by subtracting the distance between the transceiver transducers 5-1, 5-2 and the reference position 7 of the distance L, a judgment program for judging whether the distance Normalized D is in a range of D & O or not, and a program for performing various signal processing functions in the main measurement unit 4. This implements the function such as docking sound system and functions. as the normalized distance calculating means 30, the judging means 40 and the means for generating

deformation data 50.

  The display device 22 comprises a large digital display board, for example, a bulletin board

  electrically illuminated, which can be read from far away.

  The operation of the embodiment as arranged above will now be described with reference to the

  Figure 4 and Figures 1 to 3.

  When the ship 1 is docking along the mooring location 2, the docking ultrasonic sonar system 35 measures a distance from the bow and stern.

: - 2602359

  the location of the wetting 2 and the speed of movement of the bow and stern using ultrasonic waves transmitted from the immersed 5-1, 5-2 transceiver transducers, measuring an elapsed time during which the ultrasonic waves are propagate to the ship 1 and return to the transducers after reflection, and calculate the distance and

  speed based on the measured results.

  First, the elapsed time of the ultrasonic pulse

  to and return is measured by the central measurement unit 4 10 under the control of the microcomputer 14 (step 1).

  More specifically, the blower circuit 10 and the selector 11 are turned on by a transmission timing signal transmitted from the timing signal generating circuit 9. The transceiver transducers 5-1, 5-2, and stern are switched alternately by the selector 11 and driven by a high voltage pulse of the blower circuit 10 to transmit ultrasonic waves and receive reflected waves. The reflection waves as well

  received are received by the receiver 12 and the received signal is sent to the signal processing circuit 13.

  The transmission timing signal is also applied to the gate control circuit 13c of the signal processing circuit 13 to open an input gate of the counter 13d. This allows the clock pulses of the timing signal production circuit 9 to be sent to the counter 13d. The clock pulses thus sent are

counted in the counter 13d.

  The signal received from the receiver 13 is shaped into.

  pulses by the comparator 13a and the pulses are discriminated to see if the pulse duration is of a predetermined width or more. Since the transmitted waves have the predetermined width, the received waves less than the predetermined width must be considered

  like noises. This discrimination serves to prevent possible false measurements due to such noises.

  When the received signal is a pulse having the predetermined width or more, it is sent to the gate control circuit 13c. As a result, the input gate of the counter 13d is closed and counting of the clock pulses is complete. The counted value is

sent to the microcomputer 14.

  The CPU 16 of the microcomputer 14 calculates the distance

  and velocity based on the vapor counted (step 2).

  The distance and speed are calculated for the bow and stern independently, depending on the operating parameter of the program stored in the RAM 18, based on the fixed data stored in the ROM 17. For example, the distance data for the prow and the stern of the transceiver transducers 5-1, -2 are independently obtained as L1 and L2, respectively. 15 Calculation results are stored once at a region

predetermined RM 18.

  The CPU 16 reads the calculated distance data from the RAM 18 to obtain the normalized distance D of the ship 1 of the

  reference position 7 based on the data (step 3).

  The distance data L1, L2 are subtracted from the distance A between the transceiver transducers 5-1, 5-2 and the reference position A to obtain the normalized distances

  D1, D2 between the vessel and the reference position.

  The results of the calculation are applied to the display device 22 by the input / output circuit 15 and indicated numerically (step 4). In this case, the calculation results are indicated in "meter" in the present embodiment. However, another unit system such as the foot-to-thumb system can be used alternately. The 30 meter-centimeter system and the foot-to-thumb system can be

switched if desired.

  If necessary, the calculation results can be output from the driver 20 to be printed by

the printer 21.

  The operation of the present embodiment as given above is due to the function of the present embodiment as an ordinary dock landing sonar. An operation of the present embodiment due to its function

  characteristic will now be described.

  After calculating the normalized distances D1 and D2, the CPU 16 judges on the basis of the normalized distances D1 and D2 if the bow and stern of the ship 1 have already reached or not the reference position (step 5). In particular, the

  CPU 16 fulfills the judgment as to whether D1 <0, D2 <0.

  When D1 and D2 are both greater than 0, the ship 1 is outside the reference position 7 and the

  process returns to step 1 to continue the measurement.

  However, if D1 or D2 is zero or less than 0, a judgment signal is issued, which indicates that the distance D1 and / or D2

is zero or less than 0.

  Next, the CPU 16 outputs the normalized distance D1 and / or D2, which is equal to or less than 0, as the deformation data associated with the vessel 1 (step 6). More particularly, the normalized distance or distances D which is or are in the range of D <-0 is or are delivered as strain data. Since the printer 21 is provided

  as output means in the present embodiment, the deformation data is printed by the printer 21.

  In this connection, it should be noted that the values of the normalized distances D1 and D2 are generally several meters or less. For this reason, the standard distance indication unit D1, D2 is switched from "m" to "cm" by

  the CPU 16 in the present embodiment.

  The CPU 16 then judges whether an instruction for the end of the measurement has been sent externally or not (step 7). If the completion instruction of the measurement has been sent, the measurement is then completed. However, when there is no completion instruction, the process returns to step 1

to continue the measurement.

  As described above, the device of the present embodiment operates as an ordinary docking station sonar system until the vessel 1 has reached apex end positions of the parrests 3, whereas the normalizeddistances D are delivered as deformation data after the ship i has reached the apex end positions of the fenders 3. In this case, the normalized distance D indicates that the ship 1 is located within the reference position 7, close of the earth. This also indicates that the ship body 1 is being pressed against the fenders 3. In this respect, the value D also represents a deformation amount of the fenders 3. The deformation data can be controlled to watch and detect the degree

  damage to the fenders 3.

  Detection of damage or damage can be achieved simply by checking the recording output of the printer 21 periodically. Of course, it is possible to perform the detection automatically. For example, a deformation amount which corresponds to an elastic limit of the fenders 3 can be stored beforehand in the RAM 18 or the ROM 17 and the CPU 16 can be adapted to maintain a check as to whether the normalized distance D exceeds the value

  stored and emits an alarm when it exceeds the value.

  As for aging, for example, the normalized distances D can be added cumulatively and when the sum has reached a pre-established value, a message to replace

  fenders 3 by new ones will be issued.

  Although the reference position 7 is set at the extreme apex position of the fenders 3 in the present embodiment, the reference position 7 is not limited thereto and can be set, for example, at a position corresponding to an intermediate position of the fender or a little further from the coast or

Earth.

  When the intermediate position of the length of the fender 3 is chosen, the reference position may preferably be established at a position where the fender is deformable at its greatest extension in the elastic limit which is determined by the design of the fender. In this case, a deformation amount datum such as deformation within a limit where the fender barely supports a residual load can be distinguished from a deformation amount datum such as deformation which causes damage or

damage to the fenders.

  In this case, a region between the reference position 10 so selected and the apex end of the fender can be set as a near region, so that the normalized distance D can be delivered as the deformation data.

  only after the ship has reached this close region.

  By this arrangement, the normalized distance D can be obtained in the plus sign before the reference position and in

  the minus sign after the reference position.

  When the reference position is set to a position a little farther from the ground, the displacement of the ship after collision with the fenders can be recorded as the deformation data. This deformation data can produce changes in the momentum and kinetic energies of the vessel before and after the collision, as needed. In this case, a

  More detailed information on the damage of fenders can be obtained.

  As described above, according to the present embodiment, the amount of deformation of the fender can be easily known using the measurement data.

  Dock sonar system, without the use of special equipment.

  It should be noted that the speed of sound of ultrasonic waves in the sea varies according to a sea water temperature. In order to measure the propagation time precisely, the temperature of the sea water is preferably measured to change. the clock rate based on the measured temperature to correct or compensate the change with the temperature of the sound velocity. In the present embodiment, the correction of the measured data is performed in the calculation operation, according to an output of a detector

  seawater temperature (not shown).

  In the embodiment described above, the position of the ship is indicated by the normalized distance D, but it can be indicated alternatively by the distance L

  between the transceiver transducer and the ship.

  In addition, the number of transceiver transducers

  to be used in the present embodiment is not limited to two and may be one or more than two.

  The reference position established for the calculation of the normalized distance is stored in the ROM 17 in the above-mentioned embodiment but it can be memorized alternately in the RAM 17, or an external memory means.

It can be sent through a digital switch, etc.

Claims (12)

R E V E N D I C A T I ON   A method of measuring a fender deformation using a docking station sonar system in which a distance and a speed of movement of a vessel are measured from the time elapsed for the return and return of waves. ultrasound transducers which are transmitted from at least one submerged transceiver transducer to a wetting or docking location and thus received as reflection waves of the ship, characterized in that it consists in: calculating a normalized distance between a position of reference, which is set at a predetermined distance from the transceiver transducer (5-1; 5-2), and the vessel (1) based on a distance between the transceiver transducer and the ship and a distance between the transducer Transceiver and the reference position; producing the normalized distance as the ship's displacement data (1) after it has reached the reference position or a preset position near the reference position; and get a quantity of deformation of the fender   (3) from the displacement data.   2. Method according to claim 1, characterized in that the aforementioned reference position is established in order to   coincide with a normal mooring (6).   3. Method according to claim 1, characterized in that the aforementioned reference position has been established so   to coincide with a position of an apex end of the parebattage (3).   4. Method according to claim 3, characterized in that the aforesaid displacement data is used as the amount of deflection of the fender (3) when the distance between the transmitter-receiver transducer (5-1; 5-2)   and the vessel (1) is equal to or smaller than the distance between the transceiver transducer and the reference position.   5. Method according to claim 1, characterized in that the aforementioned reference position is established closer to a pier, pier, etc. that an apex end of the fender (3) and a region between the reference position and the apex end of the fenders is previously established as a near region. 6. Method according to claim 1, characterized in that the aforementioned reference position is established at a   position out of an apex end of the fender (3) 10 or farther than this.   A device for measuring a deflection of fenders in an ultrasonic docking sonar system comprising at least one transceiver transducer installed at a wetting or docking location for a vessel for transmitting and receiving waves. ultrasound and a central measurement unit for measuring a distance from the ship of the transceiver transducer and a speed of movement of the ship on the basis of an elapsed time of the ultrasonic waves transmitted and received by said transducer; characterized by comprising: normalized distance calculating means (30) for calculating a normalized distance between a reference position, which is set at a predetermined distance on the basis of the transceiver transducer, and the ship ( 1) a distance between said transceiver transducer (5-1; 5-2) and the vessel (1) and a distance between the transceiver transducer and the reference position; judgment means (40) for judging whether the vessel (1) has reached the reference position or a preset position close to the reference position; and a displacement data generating means (50) for outputting the normalized distance as ship moving data (1) when the judgment means judges that the ship (1) has reached the reference position or a near region beforehand. established; thus the deformation of the fender (3) is detected   based on the displacement data.   8. Device according to claim 7, characterized in that the aforementioned reference position is established to coincide with a normal mooring (6). 9. Device according to claim 7, characterized in that the reference position is established in order to   coincide with a position of an apex end of the parcel (3).   10. Device according to claim 9, characterized in that the aforementioned displacement data is used as the amount of deformation of the fender (3) when the distance between the transceiver transducer (5-1; 5-2) and the ship ( 1) is equal to or smaller than the distance. 15 between the transceiver transducer and the reference position. 11. Device according to claim 7, characterized in that the aforesaid reference position is established closer to a pier or pier than an apex end of the fender (3) and a region between the reference position and the apex end of the fenders is established as close region.   Device according to claim 7, characterized in that   the aforementioned reference position is set farther than an apex end of the fender (3).