JPS5838879A - Device for estimating distance of ship approaching to pier in ship guide system for approach to pier - Google Patents

Abstract

PURPOSE:To attempt at safety in guiding a ship in approach to a pier and improve reliability by judging abnormality if change in the acceleration of the ship approaching a pier based on measured distances by means of an ultrasonic wave or others is more than the specified acceleration and estimating the distance of the ship from the immediately preceding measurement value. CONSTITUTION:The distance to a ship 1 approaching a pier and the speed of ship by the change in the distance to the ship are measured by means of an ultrasonic wave sending and receiving device 2 that is immersed in the water at a dolphine pier 3, and measured distances are stored in a distance memory 18 through a counter 17 and the speed is written in a memory 21 through a velocity counter 20. An abnormal value judging circuit 30 calculates the approaching speed of the ship to the pier by the difference of the contents of the counter 20 and memory 21. If the change in the acceleration is more than a specified acceleration, the abnormality judgement signal is input to a distance estimating circuit 40. The circuit 40 upon receiving the signal calculates for estimation the distance of the ship 1 based on the memory contents immediately before that are stored in the memories 18 and 21. Accordingly misjudgement of approaching to the pier due to noises developed by the measurement of, for instance, a tug boat in the vicinity can be avoided and safety in the guiding of the approach to the pier and increased reliability can be thereby attempted.

Description

[Detailed Description of the Invention] According to the present invention, the distance and berthing speed of a ship attempting to berth at a pier such as a sea berth are measured based on the underwater propagation time of ultrasonic pulses and output as ship maneuvering information. Regarding the ship berthing guidance system, Il! The present invention relates to a berthing distance prediction device for a ship guidance system, which calculates and outputs a berthing distance in advance based on a correct berthing speed measurement value up to that point when an abnormality in an fVC measurement value is determined.

Conventionally, in this type of ship berthing guidance system using the ultrasonic pulse reflection method, at least two ultrasonic transducers are placed at a predetermined interval so as to reflect ultrasonic pulses in a direction approximately perpendicular to the ship's side. It is placed underwater on the pier side and measures the distance and berthing speed between the berthed ship and the pier based on the underwater propagation time of ultrasonic pulses emitted at regular intervals, and reports these measured values to the ship side. In particular, it enables quick and safe berthing to the pier.

However, when using the above system to guide a large vessel such as a tugboat to berth, the measured distance and speed may be affected by acoustic noise or pulsed electrical noise from the screen of the tugboat or berthed vessel. is often seen to show abnormal values.

If such measurement abnormalities continue, there is a problem in that the correct distance and berthing speed may become temporarily unknown, which may interfere with berthing guidance.

Therefore, the inventors of the present application detect the acceleration of the berthing speed of the berthed vessel, and when the detected acceleration peak shows a value that is not normally expected, the inventors determine that the measured value is abnormal, and We are proposing a device that does not output abnormal measurement values.

With such a device, abnormal measurement values can be reliably removed, and it is possible to prevent ships from being parked due to the output of abnormal measurement values.

If the normal value of total $lIM occurs sporadically, it is sufficient to remove only a small amount of total If noise or pulsed electrical noise, etc. continues to occur, the displayed distance while the total #1 abnormal value occurs will remain constant even though the ship is actually moving. The distance may remain displayed and the distance may not be displayed accurately.

The present invention has been made by focusing on such a conventional problem, and monitors the rate of change in speed over time at the time of berthing, that is, the berthing acceleration, and detects when this berthing acceleration has caused a large change that cannot normally be predicted. Sometimes, it is determined that the measured value is abnormal, and when it is determined that the speed value is abnormal, the system calculates the distance traveled by the vessel during the measurement cycle in which the abnormality occurred based on the correct speed measurement value that had been measured up to that point. Then, by subtracting this calculated distance from the distance needle side value of the cycle immediately before the abnormality was detected, the berthing distance predicted by #IJ-J is output, thereby improving the reliability and stability of berthing guidance. An object of the present invention is to provide an improved berthing distance prediction device for a ship berthing M guidance system.

Hereinafter, the present invention will be explained based on the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention.

First, to explain the configuration, for example, the front leg of the Dolphin Pier 3, which uses the dolphin pier method known as a large-tongue berthing pier, is equipped with a transducer 2 that transmits and receives ultrasonic pulses. At least two transducers 2 are installed at a predetermined interval and oriented in a direction perpendicular to the ship side of the ship 1 berthed to the dolphin 3, that is, a direction perpendicular to the normal line of the ship.

1O is a measurement unit and is connected to a transducer 2 provided underwater in the dolphin 3 via a signal cable 5. In this measuring section 10, a timer 11 generates a clock pulse at 1 second intervals, and a balsa 12 outputs an electrical transmission pulse every 1 second in accordance with this clock pulse, and transmits and receives waves.
Emit a 2-p ultrasonic pulse.

The nine ultrasonic pulses propagated through the water and reflected by the ship 1 enter the transducer 2''K again, where the pulses converted into electrical signals are amplified by the receiving amplifier 13 of the total section III 10 and then sent to the gate. 14 stop signals.

On the other hand, the transmission signal of the pulser 12 is applied to the gate 14 via the delay circuit 15, and is set to start the gate 14.

The delay circuit 15 delays the start of the gate 14 by the time required for the ultrasonic wave to propagate the distance d between the transducer 2 provided on the front leg of the dolphin 3 and the tip of the dolphin 3. It is possible to accurately measure the distance of one ton of ships.

For gate 14, pulse generator 16 shifts 50KH.
When the measurement pulse of z is given, the signal is passed through the gate 14, which is open from the start of the delay circuit 15 to the stop signal of the output of the reception amplifier 13, according to the time that the gate 14 is open. Outputs the number of needle side pulses.

The 750KHz measurement pulse output by pulse generator @16 has a frequency determined based on the time it takes an ultrasound to propagate back and forth through 1mm of water, and the pulse is the reciprocal of the time it takes an ultrasound to travel 2mm underwater. The oscillation frequency of generator 16 is determined.

In other words, since the underwater sound speed C is Ca=1500m/S, the time it takes to travel 2mm underwater is as follows. The number of measurement pulses corresponding to the time it takes for the ultrasonic waves to propagate over the distance between the dolphin 3 and the ship 1, which are outputted from 14, is calculated by the distance counter 17 and speed counter 20 using a 1.0 base 9 counter. Each is given and measured.

Here, when counting the distance in the distance counter 17, the measured value of the measurement pulse is 2×Δ
Since it represents t, the distance @L is given by L-ΔtxC (however, C-1500 m/s), and as a result, the count value of the distance counter 17 directly becomes distance data. Also, when counting the speed in the speed counter 20, the berthing speed is given as the difference between the previous distance measurement value and the current distance meter value, so the gate 14 is calculated from the previous count value counted in the distance counter 20. The measurement pulse given through the sensor, that is, the value remaining after counting down the current measurement value becomes the speed data.

The count outputs of the distance counter 17 and the speed counter 20 are stored in the distance memory 18. Speed memo + 72112) is given to each, and in distance memory 18 and speed memory 21, tie Y
The count value is memorized and held every second in synchronization with the clock pulse of llyo), and the stored distance and speed data is output.

The outputs of the distance memory 18 and speed memory 1 are given to the distance display 19 and speed display 22 via the distance prediction circuit 40, which display the berthing distance in meters and the berthing speed in CIff/@ units. .

Further, the outputs of the distance display 519 and the speed display 22 are given to the external display device 23.
3 is installed at the dolphin 30 portion, and displays speed and distance to the vessel 1.

Further, the measured values of distance and speed by the measuring section 10 are communicated to the ship 1 by radio or the like. Also, the measured values of distance and speed from the measuring section 10 are outputted to the printer 24,
It can be printed out as berthing guidance data.

On the other hand, an abnormal value determination circuit 30 and a distance meter 1111 are used as circuit means for making a prediction of the berthing distance in the present invention.
A circuit 40 is provided.

The abnormal value determination circuit 30 inputs the speedometer side value counted by the speed counter 20 and the speed measurement value stored in the speed memory 21, and the output of the speed counter 20 becomes the current speed measurement value. , the output of the speed memory 21 is the previous speed measurement value.The operation of this abnormal value determination circuit 30 is as follows.
The current speed V measurement value given by the speed counter 20 is subtracted from the previous speed needle side value from the speed meter 21 giving the previous speed measurement value, and the difference is greater than or equal to a predetermined value. Sometimes the abnormal value judgment output is sent to the distance prediction circuit 40.
．． Distance memory 18. and output to the speed memory 21. That is, in each measurement cycle, the abnormal value determination circuit 30 determines whether the value obtained by subtracting the current speed measurement value from the previous speedometer control j value, so-called berthing acceleration, significantly exceeds the expected abnormal acceleration change. It is determined that the speed measurement value is abnormal when the speed measurement value is abnormal.

Distance memory 18 from abnormal value determination circuit 30. The abnormal value determination output to the speed change memory 21 is the total I that determined the abnormal value.
Prohibits the memory update of the memory using the measured values from the distance counter 17 and speed counter 20 that corresponds to the II cycle,
The previous measurement value is maintained as is. or,
The abnormal value determination output of the abnormal value determination circuit 30 to the distance prediction circuit 40 instructs the distance prediction circuit 40 to start a child calculation of the berthing distance.

FIG. 2 is a block diagram showing the circuit configuration of the distance prediction circuit 4'0 in the embodiment of FIG. 1.

That is, the distance prediction circuit 40 is a distance filter circuit 42 .
It is composed of a speed filter circuit 44 and a control circuit 46, and the distance filter circuit 42 is given the needle-side distance stored in the distance memory 18, and the speed filter circuit 44 is given the speed memory 21. The previous measurement speed stored in is given.

As shown in FIG. 3, the specific configuration of the speed filter circuit 44 includes a speed register 45 that clears and loads the speed data from the speed memory 21 at 1-second intervals and every measurement cycle, and a speed register 45 that clears and loads the speed data from the speed memory 21 at 1 second intervals. When the value is determined, the speed register 45
It has a counter 47 that loads the count value of the speed data and counts down, and a gate 48 that is kept open while the count output of the counter 47 is generated and outputs a p-count pulse as a countdown pulse. The countdown pulse output through the counter 470
The feedback is completed as a subtraction pulse, and therefore the gate 48 is opened and a countdown pulse is output until it is transferred from the speed register 45 to the counter 47 and the count value of the nine speed data is counted down to zero.

In addition, the timer 11 (
It is generated by a 1 second timing signal and a clock pulse given by the first factor (see the first factor).

FIG. 4 shows a specific circuit of the distance filter circuit 42 installed in the distance prediction circuit 40 shown in FIG. The count value of the distance data loaded in the countdown pulse outputted through the gate 48 shown in FIG. 3 is down-counted and outputted when determining an abnormality. The output of the counter 50 becomes the berthing distance determined by the Ill calculation at the time of abnormality determination. The control circuit 46 is inputted with a direction signal indicating a berthing direction as a plus and an unberthing direction as a minus, and commands distance prediction calculation only when the direction signal is plus. The operation of the berthing distance prediction device according to the present invention will be explained with reference to FIG.

First, when the abnormal value determination circuit 30 determines that the measured value is normal, the speed filter circuit 44 shown in FIG. Next, the speed data given as the current speedometer value is loaded into the speed memory, and the speed data thus loaded into the speed register 45 is output as is. At the same time, the distance filter circuit 42 shown in FIG.
Also, the distance counter 50 is cleared by the control command from the control circuit 46, and then the current distance data stored and held in the distance memory 18 is loaded by the data command from the control circuit 46, and the distance loaded into the counter 50 is cleared. Output the 11 data.

Next, the abnormal value determination circuit 30 determines whether the measured value is abnormal and determines the running time, that is, the previous speed measured value stored in the speed memory 21 and the current speed measured value output from the speed counter 20. When the difference exceeds a predetermined value, an abnormal value judgment output is given to the distance prediction circuit 400 control circuit 46, and the control circuit 46 controls the distance filter circuit 42 and the speed f filter circuit 4 on the condition that the direction signal is positive.
4 to perform predictive calculation. The command for predictive calculation by the control circuit 46 is to load the speed data of the speed register 450 shown in FIG. This countdown pulse is fed back to the counter 47 to generate a countdown pulse until the content reaches zero, and when the content of the counter 47 reaches zero, the gate 4
8 is closed and all output of countdown pulses is stopped. Such a countdown pulse from the speed filter circuit 44 is applied to the distance filter circuit 42. As shown in FIG. 4, the distance filter circuit 4m has a counter 5o loaded with distance data (previous distance measurement value) from the distance memory The predicted berthing distance is calculated by subtracting the contents of 5o and using the result as the predicted berthing distance. By calculating the distance traveled by the ship over a measurement cycle of seconds, and subtracting this calculated distance from the previous distance meter speed value, the current berthing distance can be predicted.

FIG. 5 is a time chart showing the prediction operation of the berthing distance according to the present invention for each of the berthing speed and the berthing distance K.

In other words, if it is determined that the measurement candy is abnormal for 04 seconds from time t to time t, then the berthing distance is determined based on the speedometer value at time t, immediately before time t1 when the measurement value abnormality was determined. Time 11 to 1 when predictive calculation is performed and a measurement abnormal value occurs. The indirect berthing speed at time toK is output as is, as shown by the broken line.On the other hand, when the berthing distance is displayed based on the abnormal detected value, the value at time toK is output as is, as shown by the solid line. T! However, according to the berthing distance prediction device of the present invention, the berthing distance is displayed as changing as shown by the broken line, and the berthing distance decreases rapidly at time t.

When the measured value returns to normal after this period, the difference from the actual measured berthing distance will be extremely small.

As explained above, according to the present invention, an ultrasonic transducer is placed in the water on the pier side, and based on the underwater propagation time of ultrasonic pulses emitted at regular intervals, ships and horizontal planes are In a ship berthing guidance system that measures and outputs the distance between the ships and the berthing speed of the ship, when the difference between the previous speed needle side value and the current speedometer speed value is greater than a predetermined value,
It is determined that the detected value is abnormal, and a predictive calculation of the berthing distance is commanded. In this predictive calculation, the distance that the ship will travel in the measured time is determined based on the speedometer value before expansion, and this travel distance is calculated. Since the current berthing distance is predicted and output by subtracting it from the previous berthing distance, the abnormality meter αj value is not affected by acoustic noise or pulsed electrical noise caused by the propeller of the tugboat or #-i berthing vessel. Even in cases where berthing may continue to occur, it is possible to perform berthing guidance by predicting and outputting a berthing distance that matches the actual berthing distance, which changes from moment to moment. This has the effect of improving reliability and guiding ships to berth quickly and safely.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing one embodiment of the present invention, Fig. 2 is a block diagram showing a specific embodiment of the distance transmitter side circuit shown in Fig. 1, and Fig. 3 is the speed filter shown in Fig. 2. FIG. 4 is a circuit block diagram of the circuit, and FIG. 4 is a circuit block diagram of the distance filter circuit of FIG. 2, and FIG. 5 is a time chart showing temporal quality of the berthing distance by the predictive action of the present invention. 1... Ship 2... Sending/receiving t&, vessel 3.
...Dolphin 5...Signal cable 10...
・Measurement section 11... Timer 12... Parna 13... Reception amplifier section 14.48-... Genit 17... Distance counter 16... Pulse generator
18...Distance memory 19...Distance display
20...Speed counter 21...Speed memory
22... Speed indicator 23... External display device 24
...Printer 30...Abnormal value determination circuit 40-...
Distance prediction circuit 42...Distance filter circuit 44...Speed filter circuit 46...Control circuit 45...
・Speed register 47.50... Counter patent applicant Tokyo Keiki Co., Ltd. Patent attorney Susumu Takeuchi Figure 3 Figure 4 No. 1 and λ Figure 5 5101 et al. 20 (↓tsu)

Claims (1)

[Claims] An ultrasonic transducer is placed underwater on the pier side, and the distance between the berthing ship and the pier and the berthing speed O of the ship are determined based on the underwater propagation time of ultrasonic pulses emitted at regular intervals. In a ship berthing guidance system that measures and outputs each, when the difference between the previous speed measurement value and the current speed measurement value is greater than a predetermined value, it determines that one measurement value is abnormal and outputs it. The present invention is characterized by comprising: an abnormal value discriminating means; and a rangefinder side means for calculating K based on the previous speed measurement value and outputting the current berthing distance when the abnormal value discriminating means outputs K. A berthing distance prediction device for a ship berthing guidance system.