CN109059746A - A kind of bathymetric surveying method based on accurate POS - Google Patents
A kind of bathymetric surveying method based on accurate POS Download PDFInfo
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- CN109059746A CN109059746A CN201810634956.5A CN201810634956A CN109059746A CN 109059746 A CN109059746 A CN 109059746A CN 201810634956 A CN201810634956 A CN 201810634956A CN 109059746 A CN109059746 A CN 109059746A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
- G01B7/16—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring the deformation in a solid, e.g. by resistance strain gauge
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
- G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
- G01S19/13—Receivers
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- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves (AREA)
Abstract
The present invention relates to bathymetric surveying technical fields, more particularly to a kind of bathymetric surveying method based on accurate POS, purpose is based on GNSS positioning with high precision, pass through GNSS receiver, the three-dimensional coordinate information for the accurate POS acquisition vessel bulk measurement system that posture instrument and sounding instrument are constituted, on the basis of when resolving measuring point three-dimensional coordinate by reference ellipsoid, it is used uniformly WGS-84 coordinate system, improve in traditional water-depth measurement work, the problem of precision of Measurement results matched by plan-position with depth information, water level control, depth of water reduction etc. influence.
Description
Technical field
The present invention relates to bathymetric surveying technical fields, survey more particularly to a kind of sea-floor relief based on accurate POS
Amount method.
Background technique
This concept of bathymetric surveying is from water-depth measurement inheritance and development.Traditional water-depth measurement is mainly by fixed
Position, depth measurement and tidal observation three parts composition, acquire plan-position, the depth of water and the tidal height of underwater measuring point respectively.It is underwater solving
When the three-dimensional coordinate of measuring point, the instantaneous water of the point is acquired by corrections such as the depth of apparatus measures, the velocity of sound and instrument drinking water first
It is deep, the charted depth of the point is acquired further according to tide correction, finally matches the depth information with plan position information
Obtain the three-dimensional coordinate information of the point.In traditional water-depth measurement work, the precision of Measurement results inevitably will receive flat
Face position matches with depth information, water level control, there are the influences of error for depth of water reduction etc..Further, since depth datum
There is " step " phenomenon in the even same sea area of different waters in face, to realize that the seamless spliced of measurement data still faces larger choose
War.
Summary of the invention
The present invention proposes a kind of seabed based on accurate POS for the problems in above-mentioned background technique of effective solution
Topographic survey method simplifies work flow, reduces operating cost, realizes the Unified Expression of land-sea Measurement results.
Specific technical solution is as follows:
A kind of bathymetric surveying method based on accurate POS, comprising the following steps: step 1, data acquisition: this method
The measuring instrument that acquisition data are used mainly has: GNSS receiver, posture instrument and sounding instrument, GNSS receiver are surveyed for measuring
The three-dimensional location coordinates of ship are measured, posture instrument is used to measure the posture of surveying vessel, and sounding instrument emits sound wave realization by energy converter and changes
Can device to seabed distance detection；GNSS receiver, posture instrument and sounding instrument are centrally mounted on same straight line, wherein appearance
State instrument is placed in the position of centre of gravity of surveying vessel, and this passes straight through surveying vessel center of gravity and perpendicular to measurement longitudinal axis, three kinds of surveys
Rigid connection between measuring appratus and surveying vessel；
Coordinate system building: step 2 establishes three different coordinate systems: carrier coordinate system " G system ", attitude transducer coordinate
It is " I system " and energy converter coordinate system " H system "；
Coordinate conversion: step 3 successively arrives carrier coordinate system " G system " by energy converter coordinate system " H system ", carrier coordinate system
The coordinate of " G system " to attitude transducer coordinate system " I system " and attitude transducer coordinate system " I system " to WGS-84 coordinate system is converted,
Realize the Unified Expression of seabed observation point three-dimensional coordinate under WGS-84 coordinate system.
Preferably, coordinate system construction method is as follows in step 2:
It is longitudinal for X with ship using GNSS antenna phase center as coordinate origin GGAxis is X before being directed towardGAxis is positive；With vertical
XGAxis, direction surveying vessel starboard direction are YGAxis；ZGAxis vertically downward, XGYGZGRight hand orthogonal coordinate system is constituted, and by this coordinate
System is named as carrier coordinate system (G-XGYGZG), referred to as " G system "；Using posture instrument center as coordinate origin, hull y direction is XI
Axis is positive forward；Hull starboard direction is YIAxis, with XIAxis is vertical；It is vertically downward ZIAxis, with XIAxis and YIAxis is orthogonal at the right hand
System, and this coordinate system is named as attitude transducer coordinate system (I-XIYIZI), referred to as " I system "；With depth sounder transducer wave beam hair
Exit point is origin, XHAxis is directed toward direction of ship travel, ZHAxis is downward along instantaneous beam direction, YHAxis and XHAxis, ZHAxis constitutes the right hand
The coordinate system is named as energy converter coordinate system (H-X by orthogonal coordinate systemHYHZH), referred to as " H system ".
Preferably, coordinate is converted in step 3, and the coordinate system being finally transformed into is WGS-84 coordinate system；Not by depth of water number
According to Inversion for bottom landform, but is converted by coordinate and realize direct expression of the sea-floor relief based on reference ellipsoid.
Compared with prior art, the beneficial effects brought by the technical solution of the present invention are as follows:
Bathymetric surveying method proposed by the present invention based on accurate POS realizes data handling procedure and is not related to water level
Correction, therefore eliminate the influences of the factors to measurement accuracy such as the dynamic and static drinking water of tide, ship.Measuring point coordinate is transformed by this method
It is convenient to realize expression of the sea-floor relief in different coordinates according to actual needs in WGS-84 coordinate system；Realize land, extra large coordinate
The integration expression of system, reduces the pilot process of data processing, reduces error accumulation, improve operation to a certain extent
Precision.
Detailed description of the invention
Fig. 1 is measuring system instrument installation of the present invention and coordinate system building schematic diagram；
Fig. 2 is the transition diagram between energy converter coordinate system and carrier coordinate system；
Fig. 3 is the transition diagram between geographic coordinate system and WGS-84 coordinate system.
Specific embodiment
To be more clear the purpose of the present invention and technical solution, below the invention will be further described.
Invention describes a kind of bathymetric surveying method based on accurate POS, so-called precision POS refers to high precision
Based on GNSS positioning, by GNSS receiver, the precision measurement system of posture instrument and sounding instrument composition.Purpose, which is to acquire, to be surveyed
The three-dimensional coordinate information of ship is measured, realizes the land-sea coordinate system one under the WGS-84 coordinate system on the basis of reference ellipsoid
Change expression；Improve in traditional water-depth measurement work, the precision of Measurement results matched by plan-position with depth information, water level control
The problem of system, depth of water reduction etc. influence.
The present invention is based on the bathymetric surveying methods of accurate POS, by data acquisition, coordinate system building, coordinate conversion three
A major part composition, detailed process is as follows:
Step 1, data acquisition, the measuring instrument that this method acquisition data are used mainly have: GNSS receiver, posture instrument
And sounding instrument.GNSS receiver is used to measure the three-dimensional location coordinates of surveying vessel, and posture instrument is used to measure the posture of surveying vessel, surveys
Deep instrument emits sound wave by energy converter and realizes the detection of energy converter to seabed distance.The design of measuring system of this method is different from biography
The place of system bottom topography survey system is: posture instrument being placed in the position of centre of gravity of surveying vessel, makes the center of posture instrument with survey
The center of gravity for measuring ship is overlapped；GNSS antenna is installed and when sounding instrument, make they center and posture instrument center point-blank,
This passes straight through surveying vessel center of gravity and perpendicular to measurement longitudinal axis；GNSS antenna, three kinds of instruments of posture instrument and sounding instrument and ship
Between be rigidly connected.Then it can be used for after systematic error, calibration are qualified before operation by the way that instrument is installed progress Accurate Calibration and determined
Marine field survey operation.
Step 2, it is to sit that coordinate system building, which is mainly established on surveying vessel with three respective centers of main observation instrument,
Mark three coordinate systems of origin: carrier coordinate system (G system), attitude transducer coordinate system (I system) and energy converter coordinate system (H system).
Specific construction method is as follows: longitudinal for X with ship using GNSS antenna phase center as coordinate origin GGAxis is X before being directed towardGAxis is just
To；With vertical XGAxis, direction surveying vessel starboard direction are YGAxis；ZGAxis vertically downward, XGYGZGRight hand orthogonal coordinate system is constituted,
And this coordinate system is named as carrier coordinate system (G-XGYGZG), referred to as " G system ".Using posture instrument center as coordinate origin, hull is vertical
Axis direction is XIAxis is positive forward；Hull starboard direction is YIAxis, with XIAxis is vertical；It is vertically downward ZIAxis, with XIAxis and YIAxis
Attitude transducer coordinate system (I-X is named as at right hand rhombic system, and by this coordinate systemIYIZI), referred to as " I system ".It is changed with sounding instrument
Energy device beam transmission point is origin, XHAxis is directed toward direction of ship travel, ZHAxis is downward along instantaneous beam direction, YHAxis and XHAxis, ZH
Axis constitutes right hand orthogonal coordinate system, which is named as energy converter coordinate system (H-XHYHZH), referred to as " H system " is (such as Fig. 1 institute
Show).The purpose for establishing these three coordinate systems is to facilitate intermediate conversion result to move while simplifying flow chart of data processing for his use.
The coordinate system that coordinate conversion is finally transformed into step 3 is WGS-84 coordinate system, realizes that sea-floor relief is detached from the depth of water
The direct expression of constraint.According to the definition of coordinate system in step 2 it is found that X in H systemHAxis should theoretically be parallel to the X in G systemG
Axis, the conversion of H system to G system only need to be by H systems around XHAxis, which rotates an angle, θ (field angle), can just make three seats of H system and G system
Parameter is corresponding parallel (as shown in Figure 2), corresponding spin matrix are as follows:
But actually due to equipment placement error and influence of the environmental factors such as wind, stream to ship under sail, in difference
The course of moment ship will not be generally completely coincident, therefore there is also error angle alphas between them1, β1, γ1.Assuming that comprehensively considering
Error angle afterwards is α, and beta, gamma, then by H system, rotating around X, Y, Z axis, (X, Y, Z axis here can refer to transitional in rotary course
Reference axis) rotation alpha, beta, gamma angle, then the spin matrix for being transformed into G system by H system is writeable are as follows:
The spin matrix R converted from energy converter coordinate system (H system) to carrier coordinate system (G system) can be writtenG:
RG=RG2RG1 (3)
Since the coordinate origin of H system and G system is not overlapped, therefore to realize that coordinate conversion between the two also needs to carry out origin
Translation, if the space vector between origin is THG, then coordinate (X of the one point S of seabed in carrier coordinate systemSG,YSG,ZSG) can indicate
Are as follows:
[XSG,YSG,ZSG]T=RG[0 0 D]T+THG (4)
Wherein, D is the distance of beam transmission point H to seabed point S, the wave beam two-way time that can be recorded according to POS system
In conjunction with Sound speed profile, pass through principle type:
It acquires.D indicates the distance from launch point to reflection point in formula, and V (t) is the velocity of sound on acoustic wave propagation path, and t is sound
The time of wave roundtrip propagation.In actual job, the mean propagation velocity V of the sound wave from sea to seabed is generally takenmInstead of V (t),
Therefore principle type can be written as d=1/2Vmt。
Similarly, transition matrix of the G system to I system:
Then coordinate (X of the seabed point S in I systemSI,YSI,ZSI) writeable are as follows:
[XSI,YSI,ZSI]T=RI[XSG,YSG,ZSG]T+TGI (7)
Wherein, α2, β2, γ2For three installation error angles existing for due to equipment placement；TGIIt is flat for the origin of G system to I system
The amount of shifting to.
Similarly, by the transition matrix R of I system to WGS-84 coordinate systemW=RW1RW2, in which:
For the spin matrix of I system with being transformed into east northeast geographic coordinate system.R, p, y respectively represent POS system posture instrument and measure
Ship transient posture angle roll, pitch and yaw.
For the spin matrix converted from geographic coordinate system to WGS-84 coordinate system, it is latitude (such as Fig. 3 institute that λ, which is longitude, φ,
Show).
The above is only a preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also answered
It is considered as the protection scope of invention.
Claims (3)
1. a kind of bathymetric surveying method based on accurate POS, comprising the following steps: step 1, data acquisition: this method is adopted
The measuring instrument that collection data are used mainly has: GNSS receiver, posture instrument and sounding instrument, GNSS receiver is for measuring surveying vessel
Three-dimensional location coordinates, posture instrument is used to measure the posture of surveying vessel, and sounding instrument emits sound wave realization energy converter by energy converter
To the detection of seabed distance；GNSS receiver, posture instrument and sounding instrument are centrally mounted on same straight line, wherein posture instrument
It is placed in the position of centre of gravity of surveying vessel, and this passes straight through surveying vessel center of gravity and perpendicular to measurement longitudinal axis, three kinds of measuring instruments
Rigid connection between device and surveying vessel；
Coordinate system building: step 2 establishes three different coordinate systems: carrier coordinate system " G system ", attitude transducer coordinate system " I
System " and energy converter coordinate system " H system "；
Coordinate conversion: step 3 successively arrives carrier coordinate system " G system " by energy converter coordinate system " H system ", carrier coordinate system " G
System " converts to attitude transducer coordinate system " I system " and attitude transducer coordinate system " I system " to the coordinate of WGS-84 coordinate system, real
The Unified Expression of seabed observation point three-dimensional coordinate under existing WGS-84 coordinate system.
2. the bathymetric surveying method according to claim 1 based on accurate POS, which is characterized in that sat in step 2
Mark system construction method is as follows:
It is longitudinal for X with ship using GNSS antenna phase center as coordinate origin GGAxis is X before being directed towardGAxis is positive；With vertical XG
Axis, direction surveying vessel starboard direction are YGAxis；ZGAxis vertically downward, XGYGZGRight hand orthogonal coordinate system is constituted, and by this coordinate system
It is named as carrier coordinate system (G-XGYGZG), i.e. carrier coordinate system " G system "；Using posture instrument center as coordinate origin, hull longitudinal axis side
To for XIAxis is positive forward；Hull starboard direction is YIAxis, with XIAxis is vertical；It is vertically downward ZIAxis, with XIAxis and YIAxis is at the right side
Hand rhombic system, and this coordinate system is named as attitude transducer coordinate system (I-XIYIZI), i.e. attitude transducer coordinate system " I system "；
Using depth sounder transducer beam transmission point as origin, XHAxis is directed toward direction of ship travel, ZHAxis is downward along instantaneous beam direction, YH
Axis and XHAxis, ZHAxis constitutes right hand orthogonal coordinate system, which is named as energy converter coordinate system (H-XHYHZH), i.e. energy converter
Coordinate system " H system ".
3. the bathymetric surveying method according to claim 1 based on accurate POS, which is characterized in that sat in step 3
Mark conversion, the coordinate system being finally transformed into is WGS-84 coordinate system；Not by bathymetric data Inversion for bottom landform, but pass through seat
Direct expression of the sea-floor relief based on reference ellipsoid is realized in mark conversion.
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| CN111350214A (en) * | 2020-03-23 | 2020-06-30 | 中交第三航务工程局有限公司江苏分公司 | Multi-beam underwater steel pipe pile position measuring method |
| CN114114361A (en) * | 2022-01-27 | 2022-03-01 | 山东科技大学 | Offshore platform precise positioning auxiliary system based on GNSS and working method |
| WO2022062158A1 (en) * | 2020-09-22 | 2022-03-31 | 广东工业大学 | Acoustic positioning monitoring method for marine engineering floating platform |
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| CN114114361B (en) * | 2022-01-27 | 2022-04-29 | 山东科技大学 | Offshore platform precise positioning auxiliary system based on GNSS and working method |
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