JP2001116829A - Method of holding position and azimuth for underwater acoustic tester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hold a transducer in a proper position and a proper direction. SOLUTION: A submerged body 15 mounted with the transducer 13 and a gyro system 16 for measuring a sound level from an underwater moving body 10 and for emitting a sound from itself to be measured by the moving body 10 is suspended from a marine floating body 11, a thruster 17 is attached to the submerged body 15, a GPS position measuring instrument 20 is mounted on the floating body 11, and the thruster 17 is controlled based on a position provided by the position measuring instrument 20 and a azimuth provided by gyro system measurement to hold the transducer 13 mounted on the submerged body 15 in the set position and the set azimuth.

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 maintaining the position and orientation of an underwater acoustic test apparatus for measuring the position of an object moving in the sea.

[0002]

2. Description of the Related Art In order to transmit a loud sound from an object moving in the sea or a sound of an accurate magnitude toward a moving object, a pinger (sonic wave oscillator) and a transducer are usually used, and an ultrasonic wave is transmitted from the pinger. A sound wave such as a pulse is transmitted, the sound under the sea is picked up by a transducer, the direction and distance of the moving object are obtained, and the position and orientation of the moving object in the sea are measured.

The pingers may be mounted on a moving object to track the position of the moving object, or may be mounted on the transducer.

[0004] This transducer is a simple type,
Usually, the buoy is suspended from the buoy. In this case, the buoy is caused to flow by a tidal current or the like, and the position and orientation of the transducer are largely shifted.

[0005]

As described above, when the position and orientation of the transducer are shifted, it is extremely difficult to directly correct the position and orientation.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems and to provide a method and apparatus for maintaining the position and orientation of an underwater acoustic test apparatus capable of holding a transducer at an appropriate position and orientation.

[0007]

In order to achieve the above object, the invention of claim 1 measures the loudness of a sound from a moving object in the sea from a floating object on the sea, or emits a sound by itself to detect a sound in the sea. A submerged body equipped with a transducer to be measured by a moving object is suspended, a thruster is attached to the submerged body, and a GPS position measuring device is mounted on the floating body on the sea.
This is a method for controlling the thruster based on the position obtained by the S position measurement to maintain the transducer mounted on the underwater body at a set position and the position and orientation of the underwater acoustic test apparatus.

According to a second aspect of the present invention, a gyro system is mounted on the underwater body, and the gyro system measures the azimuth of the underwater body, and controls a thruster based on the azimuth and the position obtained by the GPS position measurement. 2. The method according to claim 1, wherein the transducer mounted on the underwater body is held at a set position and orientation.

According to a third aspect of the present invention, the marine floating body comprises a boat equipped with a propulsion device or a buoy provided with a thruster and the like, and corrects the position of the marine floating body based on the position obtained by GPS position measurement. A method for maintaining the position and orientation of an underwater acoustic test apparatus according to claim 1 or 2.

According to a fourth aspect of the present invention, there is provided the underwater acoustic test apparatus according to the first or second aspect, wherein the floating object on the sea is a buoy moored from the sea floor.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

In FIG. 1, reference numeral 10 denotes a moving object that moves in the sea, and reference numeral 11a denotes a boat as a floating body on the sea for positioning the moving object 10, which has a propulsion unit 12. An underwater body 15 is suspended from the boat 11a via a cable 14. On the underwater body 15, the transducer 13 and the gyro system 16 are mounted.

The underwater body 15 is formed in, for example, a box shape, and a thruster 17 is attached to each side surface of the underwater body 15, so that the attitude of the underwater body 15 can be freely controlled.

The transducer 13 is used to move the moving object 1
The sound wave S from 0 is detected, and its direction and distance are detected.

The boat 11a has a plurality of GPS (Globa
l Positioning System) An antenna 19 for receiving a radio wave from a satellite 18 and a GPS position measuring device 20 for measuring a position based on the received radio wave are provided.

In the above, the position of the boat 11a for measuring the moving object 10 is determined in advance, and the GPS position measuring device 20 determines the current position based on reference signals from a plurality of GPS satellites 18 in order to maintain the position. Calculation is performed to determine a deviation from the set position, and the propulsion unit 12 is driven using the deviation as a correction value to perform control so as to maintain the set position.

Further, since the underwater body 15 is swept to some extent by the tidal current, the thruster 17 is controlled so as to be located immediately below the boat 11a so that the position is appropriately maintained. Further, a gyro system 16 is provided in the underwater body 15, the direction of the gyro system 16 is determined by the gyro system 16, and the transducer 1 is
3 is controlled so that it faces the set direction.

As described above, the propulsion unit 12 of the boat 11a
Thus, the position of the underwater body 15 is properly maintained by the thruster 17 and the azimuth of the transducer 13 can be controlled, so that the position of the moving object 10 in the sea can be accurately grasped.

The boat 11a may be one that can be wirelessly operated by a radio control or the like. In this case, the boat 11a is always circulated with an appropriate radius so as not to be swept away by ocean currents or the like.
1a may be moved.

FIG. 2 shows another embodiment of the present invention, in which a box-shaped buoy 11b is used as a floating body on the sea, and four thrusters 21 are attached to the side of the buoy 11b.
When the position is measured by the S position measuring device 20, the thruster 21 is appropriately controlled so as to maintain the position, and the set position is maintained.

FIG. 3 shows still another embodiment of the present invention. A buoy 11c is used as a floating body on the sea, and the buoy 11c is moored to a seabed 23 by a mooring cable 22 to move underwater. The position of the object 10 is measured.

[0022]

In summary, according to the present invention, the position of a floating object on the sea is detected using a GPS system, and the position of the floating object on the sea is corrected so that the position becomes a set position.
Further, by using a gyro system to detect the direction of the underwater body and correcting the direction of the underwater body so that the direction becomes the set direction, an acoustic test of a moving object in the sea can be accurately performed.

[Brief description of the drawings]

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

FIG. 2 is a schematic view showing another embodiment of the present invention.

FIG. 3 is a schematic diagram showing still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Moving object 11a Boat (sea floating body) 11b, 11c Buoy (sea floating body) 12 Propeller 13 Transducer 15 Underwater body 17 Thruster 18 GPS satellite 20 GPS position measuring device

Claims (4)

[Claims] An underwater body mounted with a transducer for measuring a loudness of a sound from a moving object in the sea from a floating body on the sea or emitting a sound to measure the moving object in the sea by itself. A thruster is mounted on the underwater body, and a GPS position measuring device is mounted on the floating body on the sea, and the thruster is controlled based on the position obtained by the GPS position measurement to hold the transducer mounted on the underwater body at a set position. A method for maintaining the position and orientation of an underwater acoustic test device, characterized by: 2. A gyro system is mounted on the underwater body, and the gyro system measures the direction of the underwater body,
2. The method according to claim 1, wherein the thruster is controlled based on the azimuth and the position obtained by the GPS position measurement, and the transducer mounted on the underwater body is held at the set position and azimuth. 3. The floating object according to claim 1, wherein the floating object comprises a boat equipped with a propulsion device or a buoy equipped with a thruster, and corrects the position of the floating object based on a position obtained by GPS position measurement. The method for maintaining the position and orientation of the underwater acoustic test device described in the above. 4. The method according to claim 1, wherein the floating object on the sea is a buoy moored from the sea floor.