JPH10332825A - Method and system for surveying topography of seabed - Google Patents

Abstract

PROBLEM TO BE SOLVED: To represents the seabed with an extremely high accuracy by adding a precise time lag measured by UTC time (universal time convention) to the rolling or azimuth data of survey boat and determining the topography of seabed by synchronizing these data entirely. SOLUTION: In the inventive method and system for surveying the topography of seabed, the coordinate position of a sonar depth gauge being set in a survey boat is obtained, along with the measuring time thereof, based on GPS signals received from satellites and stored. Seabed depth information from the sonar depth gauge and rolling information of the boat from a rolling sensor of the survey boat are added with a precise time lag determined with reference to a timing pulse of UTC time obtained through GPS and stored. Coordinate position of the sonar depth gauge is then operated along with the seabed information and the rolling information at a time closest to the measuring time thereof and the topography of seabed is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a device for measuring the seafloor topography, and more particularly to a method and a device for measuring seafloor topography using a GPS and a sonar sounder.

[0002]

2. Description of the Related Art In general, in the construction of breakwaters, first, rubble is thrown in by a gut ship, a foundation mound is created by machine leveling, and then a caisson is installed and built as a breakwater.

[0003] Important management items of this construction include rubble input management and mound surveying. Red management by Redman has conventionally been used for rubble input management, and acoustic measurement has been used for preliminary measurement and mound inspection after stoning. Using a detector. These survey methods are spot or line surveys, and the sea bottom cannot be surveyed and managed on the surface. For this reason, it is difficult to grasp the location and amount of the large irregularities after the stone is thrown, and large irregularities are found during leveling work, causing rework such as refilling the stones and collecting excess, and greatly increasing the leveling efficiency. Affected.

In order to solve such a problem, a rubble input management system has been developed which can use a multi-beam sonar to measure a search width of 90 ° at a time with a sharp directional angle and can measure the sea floor in a wide area. I have.

[0005] In such a system, the search direction of the sonar can be turned mechanically, so that the surveying vessel can be moored to a gut ship, and the non-landing condition immediately after the stoning can be measured from one point without moving, so that the surveying vessel can be immediately measured. It can be reflected in the stoning management. Further, if the surveying ship is navigated, the construction surface after the stoning or after the leveling can be measured over a wide range.

FIGS. 2 and 3 are explanatory views of such a conventional method and apparatus for measuring the seafloor topography, wherein a sonar sounder 2 provided on the bottom of a survey ship 1 has a beam width of 1.5 seconds, for example, for 0.3 second. The sonar sounder 2 is repetitively turned, for example, by 90 ° by a revolving means (not shown).
Is moved in a direction orthogonal to the turning direction, and the coordinate position of the sonar sounder 2 is determined by the GPS fixed station 3 provided on the non-moving part and the GPS mobile station 4 provided on the survey ship 1, and from the sonar sounder 2 Of the sea bottom is calculated by an arithmetic processing unit (not shown), and is displayed three-dimensionally as shown in FIG.

FIGS. 5 and 6 show a case where the seafloor topography is measured by sweeping the ultrasonic beam from the sonar sounder 2 in one direction and a direction orthogonal thereto without moving the surveying vessel 1. FIG.

[0008]

However, such a conventional method and apparatus have a drawback that an error occurs in a measured value due to a fluctuation of a surveying ship and a change in direction, and an accurate seabed topography cannot be obtained.

The present invention has been made to eliminate such disadvantages.

[0010]

SUMMARY OF THE INVENTION A method and apparatus for measuring the seafloor topography according to the present invention include a GPS fixed station provided on a non-moving part, a GPS mobile station and a sonar sounder provided on a survey ship, and a sonar sounder. Turning means for repeatedly turning in a desired range, means for detecting the motion of a surveying vessel, and the precise time based on the timing pulse of the Coordinated Universal Time obtained from GPS, the seafloor depth information from the sonar sounder and the above-mentioned motion detection Means for adding a time tag to the motion information of the survey ship obtained by the means, coordinates and measurement time of the sonar sounder obtained from information from the GPS fixed station and the GPS mobile station, the sonar sounder and the motion detection It is characterized by comprising means for storing information from the means, and an arithmetic processing unit for calculating and expressing the seabed topography from the information stored by the storage means.

Further, the method and apparatus for surveying the seafloor topography according to the present invention include a GPS fixed station provided in a non-moving part, a GPS mobile station and a sonar sounder provided on a survey ship, and a sonar sounder which is repeated in a desired range. Turning means for turning, motion detection means and direction detection means of the surveying ship, and precise time based on the timing pulse of the Coordinated Universal Time obtained from GPS as the seafloor depth information from the sonar sounder and the motion detection Means for adding a time tag to the shaking information and the azimuth information of the survey ship obtained by the means and the azimuth detecting means;
Means for storing the coordinates and measurement time of the sonar sounder obtained from information from the S fixed station and the GPS mobile station, information from the sonar sounder and the shaking detecting means and azimuth detecting means, and storing by the storing means And an arithmetic processing unit that calculates and expresses the seabed topography from the obtained information.

The method of surveying the seafloor topography according to the present invention comprises the steps of obtaining and storing the coordinate position of a sonar sounder provided on a survey ship and the measurement time from a GPS signal from an artificial satellite; Adding a precision time as a time tag based on the timing pulse of the Coordinated Universal Time obtained from GPS to the seafloor depth information and the motion information of the survey ship, and storing the time position, and the coordinate position of the sonar sounder as the measurement time Calculating the bottom sea topography by calculating the sea bottom depth information and the motion information of the ship at the closest time.

[0013] In addition, the method for surveying the seafloor topography of the present invention comprises the steps of obtaining and storing the coordinate position and the measurement time of a sonar sounder provided on a survey ship from a GPS signal from an artificial satellite; Adding and storing a precise time as a time tag based on the timing pulse of the Coordinated Universal Time obtained from GPS to the seafloor depth information, the motion of the surveying vessel, and the bearing information, and measuring the sonar sounder coordinate position Calculating together with the seabed depth information, ship sway information and azimuth information at the time closest to the time to display the seafloor topography.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

In the present invention, a survey sensor 1 is provided with a sway sensor and a direction sensor (both not shown), and the GPS survey data and other measured data are synchronized as shown in FIG. Therefore, in addition to the positioning data from the GPS, a clock of 10 ms in the arithmetic processing unit is synchronized with a UTC (Coordinated Universal Time) output from the GPS every positive second and a 1 pps pulse signal indicating the timing of the time. And add the UTC time to this to create a precise time in 10 millisecond increments. This time is used as a time tag managed by the present invention, and when each measurement data is received, a time tag is attached to this data value to temporarily store the past data. In this way, of the seafloor depth information from the sonar sounder and the sway information from the sway detector and / or the azimuth information from the azimuth detector, search for the measurement data at the time closest to the GPS positioning time, Synchronous processing is performed in units of 10 mm.

[0016]

As described above, according to the present invention, the precise time using the UTC time is added as a time tag to the swaying and azimuth data of the survey ship, and all the data are synchronized with time to determine the shape of the seabed. There is a great benefit to be able to represent the ocean floor with extremely high precision.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a seafloor topographical survey method and apparatus of the present invention.

FIG. 2 is an explanatory diagram of a conventional seafloor topographic surveying method and apparatus.

FIG. 3 is an explanatory diagram of a conventional seafloor topographic surveying method and apparatus.

FIG. 4 is a bird's-eye view of the seabed obtained by the method of FIG. 3;

FIG. 5 is an explanatory diagram of another conventional seafloor topographic surveying method and apparatus.

FIG. 6 is a bird's-eye view of the seabed obtained by the method of FIG. 5;

[Explanation of symbols]

 1 surveying vessel 2 sonar sounder 3 GPS fixed station 4 GPS mobile station

Claims (4)

[Claims] 1. A GPS fixed station provided in a non-moving part, a GPS mobile station and a sonar sounder provided on a survey ship, turning means for repeatedly turning the sonar sounder in a desired range, and The motion detection means and the precise time based on the timing pulse of the Coordinated Universal Time obtained from the GPS are added as time tags to the seafloor depth information from the sonar sounder and the motion information of the survey ship obtained by the motion detection means. Means, means for storing coordinates and measurement time of the sonar sounder obtained from information from the GPS fixed station and the GPS mobile station, information from the sonar sounder and the shaking detecting means, and storage by the storage means. And an arithmetic processing unit that calculates and expresses the seafloor topography from the obtained information. 2. A GPS fixed station provided on a non-moving part, a GPS mobile station and a sonar sounder provided on a surveying ship, turning means for repeatedly turning the sonar sounder in a desired range, and Movement detecting means and azimuth detecting means, GPS
The precise time based on the Coordinated Universal Time timing pulse obtained from the above is added as a time tag to the seafloor depth information from the sonar sounder and the motion and direction information of the surveying vessel obtained by the motion detection means and direction detection means. Means, and the coordinates and measurement time of the sonar sounder obtained by the information from the GPS fixed station and the GPS mobile station, means for storing information from the sonar sounder and the motion detection means and the direction detection means, A submarine topographic surveying apparatus comprising: an arithmetic processing unit that calculates and expresses a submarine topography from the information stored by the storage means. 3. A step of obtaining and storing the coordinate position of a sonar sounder provided on the surveying ship and its measurement time from a GPS signal from an artificial satellite, information on the seabed depth from the sonar sounder and information on the motion of the surveying ship. Adding a precise time based on the timing pulse of the Coordinated Universal Time obtained from the GPS as a time tag and storing the time tag, and storing the coordinate position of the sonar sounder with the seafloor depth information at the time closest to the measured time and And a step of displaying the seafloor topography by calculating together with the ship's motion information. 4. A step of obtaining and storing a coordinate position and a measurement time of a sonar sounder provided on a surveying ship from a GPS signal from an artificial satellite, and information on seabed depth from the sonar sounder.
Adding and storing a time tag with a precise time based on the coordinated universal time obtained from GPS as a time tag to the motion information and heading information of the surveying vessel, and storing the sonar sounder coordinate position closest to the measurement time. A step of calculating the seafloor topography by calculating the seafloor depth information of the time, the sway information of the ship, and the azimuth information to display the seafloor topography.