JP2816811B2 - Vessel navigation detection method and apparatus based on water pressure change - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for detecting a passing pressure for detecting a change in water pressure generated when a ship is moving in the vicinity in order to determine the size and speed of the ship moving in the vicinity. It is.

[0002]

2. Description of the Related Art It has been found that the pressure of water in the water changes in the negative direction when a ship moves in the vicinity, and the magnitude and duration of the change in the negative pressure are related to the size of the ship and the navigation speed. Conventionally, the output signal of the detector for detecting the negative pressure change is determined by a discriminator, and the magnitude and the duration of the negative pressure change in the water pressure each exceed a certain value.
Judgment of navigation was being made.

[0003] However, in the conventional navigation method described above, when there is a wave (waves or undulations on the water surface), the pressure in the water changes alternately in both positive and negative directions due to the waves even when the ship is not navigating. (The period and the amplitude of the change are related to the magnitude of the wave), so that there is a problem that an erroneous determination is often made.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and a device for detecting a ship's navigation which does not malfunction due to a change in water pressure due to waves.

[0005]

According to the present invention, as shown in FIG. 1, an output signal from a water pressure detector 10 is measured by a period measuring device 30.
Means for sending to the moving linear averager 20, means for sending the output of the period measuring device 30 to the exponential averaging device 40 to obtain an average period over a long time, and moving linear averaging device 20 so that the average period becomes the averaging time. The present invention is a navigation detection method and an apparatus for detecting a change in water pressure, comprising means for sending an output of the moving linear averager 20 obtained by controlling the traveling linear averager 20 to a navigation identification device 50 and determining navigation.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG.
0 is a water pressure detector for converting a change in water pressure into an electric signal, and 30 is a period measuring device, which counts the time from the previous similar change every time the signal from the water pressure detector 10 exceeds a certain value. It is. Reference numeral 40 denotes an exponential averager for exponentially averaging the count values, and reference numeral 20 denotes a moving linear averager, which outputs a signal from the water pressure detector 10 with an average time equal to the average value of the cycle obtained from the exponential averager 40. Average. Numeral 50 denotes a pass-through discriminator for discriminating the pass / fail based on the average result.

The moving linear averager 20 outputs a simple average of values from the past to the present for a fixed average time with respect to the input time signal, and the exponential averager 40 outputs For an input sequence Xn input at certain time intervals, an output sequence Yn

Yn = kXn + (1-k) Yn- ₁

[0009] It is obtained from the following.

When the output signal of the water pressure detector 10 changes due to waves, the change is substantially equal in both the positive and negative directions, so that the period is measured by the period measuring device 30 and averaged by the exponential averaging device 40. The average is
Even if the wave cycle changes in the long term due to the characteristic of the exponential averaging, it always averages the latest cycle.

The moving linear averager 20 performs moving linear averaging of the signal of the water pressure detector 10 with an average time equal to the average period. Because of the linear averaging characteristic, the averaging result is zero for positive / negative symmetric signals having a period equal to the averaging time, so that a water pressure change signal due to waves is not output.

On the other hand, a change in water pressure when a ship travels in the vicinity mainly occurs only in the negative direction.

In FIGS. 2 to 6, the Y-Y axis indicates a change in water pressure and the X-axis indicates elapsed time. Detected by a water pressure detector,
The change in the water pressure due to the wave shown in FIG. 2 or the change in the water pressure due to the wave shown in FIG. 3 and the change in the water pressure due to the passage are superimposed on the passage discriminator 50 in FIG. As shown, a signal in which the wave signal has been removed and the navigation signal has been emphasized is sent, and the navigation of the ship can be easily determined without error.

[0014]

Since the present invention is configured as described above,
It is possible to remove a change in water pressure due to the waves and to emphasize the passage signal to the passage judgment device 50, and it is possible to easily judge the passage of the ship without error, which is extremely useful.

[Brief description of the drawings]

FIG. 1 is a device configuration diagram showing an embodiment of the present invention.

FIG. 2 is a waveform diagram showing a change in water pressure due to only waves.

FIG. 3 is a waveform diagram showing a change in water pressure due to waves and ship navigation.

FIG. 4 is a waveform diagram showing a change in water pressure due to only a wave sent to a navigation detector.

FIG. 5 is a waveform diagram showing a change in water pressure due to a wave sent to the navigation detector and a ship traveling.

[Explanation of symbols]

 Reference Signs List 10 water pressure detector 20 moving linear averager 30 period measuring instrument 40 exponential averager 50 overtravel detector

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yuji Ukita 2507-915 Ichinomatsu Mitsuyama, Gobara-cho, Kure-shi, Hiroshima Hiroshima Office of Marine Electronics Industry Co., Ltd. (56) References JP-A-5-248799 (JP, A) JP-A-5-118022 (JP, A) JP-A-4-86997 (JP, A) JP-A-58-55809 (JP, A) JP-A-3-16742 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) G01D 21/00 G01B 13/00 G01D 21/02 G01P 5/00

Claims (2)

(57) [Claims] Means for sending an output signal from a water pressure detector to a period measuring device and a moving linear averager, and an output of the period measuring device to an exponential averaging device.
0), means for obtaining an average period over a long period of time, and the output of the moving linear averager (20) obtained by controlling the moving linear averager (20) so that the average period becomes the average time. A navigation detection method for detecting a change in water pressure which is sent to an overdetermination device (50) and determines means of navigation. 2. A water pressure detector (10), and a cycle measuring device (3) for sending an output signal from the water pressure detector (10).
0), a moving linear averager (20), an exponential averager (40) for obtaining an average period over a long time based on the output of the period measuring device (30), and a moving linear average so that the average period becomes the average time. A passing linear detector (50) based on an output of the moving linear averaging device (20) obtained by means for controlling the detector (20);