RU2561229C1 - Buoy for determination of characteristics of sea wind waves - Google Patents

Abstract

FIELD: instrumentation.

SUBSTANCE: device comprises a solid metal casing (3), inside of which there is a control module (1) with an optional GPS unit, a power supply source (2), a digital three-component accelerometer (15), a three-component magnetometer (17). In the lower part of the casing (3) there is a sliding anchor device (4), and also a stabilising device (5). The stabilising device (5) is made in the form of wings coupled with the casing (3) by means of hinged joints (6) and rubber shock absorbers (7). The power supply source (2) is equipped with a generator coupled with the stabilising device (5). The casing (3) in its underwater part is equipped with a damping device (14), made of an attachment, equipped with the even number of tabs. Tabs of the attachment are fixed to the buoy casing with the help of flat springs. Besides, even tabs are fixed as inclined downwards, and odd tabs - as inclined upwards. The optional GPS unit of the control module (1) comprises a four-channel receiver of satellite signals made as capable of simultaneous measurement of delta pseudo-ranges to four artificial satellites of the Earth. At the same time the receiver of the satellite communication channel comprises a navigation filter for buoy movement modelling. The casing (3) is equipped with elements (8) of the parachute system and a device (13) for transfer of information along radio and satellite communication channels. A digital three-component accelerometer (15) and a three-component magnetometer (17) are placed in a single body (16).

EFFECT: increased accuracy of determination of characteristics of sea wind waves.

1 dwg

Description

The invention relates to the field of hydrometeorology and can be used to determine the characteristics of sea wind waves, and can also be used to measure hydrometeorological parameters by means of registration placed on buoys.

Known devices for measuring hydrometeorological parameters by means of registration placed on buoys (copyright certificate SU No. 1280321, 12/30/1986; copyright certificate SU No. 1280320, 12/30/1986; copyright certificate SU No. 1712784, 02/15/1992; JP patent No. 60107490, 12.06 .19S5 [1-4]), consist of a hull, a mast with a device for transmitting information via radio and satellite communication channels, a wind parameter meter, an atmospheric pressure meter, an air temperature sensor, a water temperature sensor, a beacon, a radar corner reflector, a module I control with an optional GPS unit, an information memory unit, a central module with a controller, a wave height and orientation meter, a speed and direction sensor, salinity, electrical conductivity, turbidity, oxygen content, pH ions, an oxidation / reduction process controller, power source.

A common disadvantage of the known devices for determining the characteristics of sea wind waves [1-4] is the low structural reliability of both the buoy itself and the measuring instruments and power source, which significantly increases the complexity of using these tools for a long time interval of marine research.

There is also known a device for measuring hydrometeorological parameters by means of registration placed on buoys (patent RU No. 2238757, July 10, 2008) [5], which consists of a cylindrical body, a mast with a device for transmitting information via radio and satellite communication channels, and a parameter meter wind, atmospheric pressure measuring instrument with a barport including a separation chamber, a desiccant, a flexible connecting pipe, a lockable channel, an air collector, a ball valve located inside the air intake pipe, sensors and air temperature, a water temperature sensor, a beacon, a radar angle reflector, a control module with an optional GPS unit, an information memory unit, a central module with a controller, a wave height and orientation meter, a speed and direction sensor, salinity, electrical conductivity, turbidity sensors , oxygen content, pH ion content, oxidation / reduction process controller, power source, in which, unlike the known analogues [1-4], the buoy’s body is made of reinforced plastic, and the lower part is made in the form of a metal base equipped with a stabilizing device, the upper part of the body is made of foam in the form of a cone expanding to the top at an angle of 30 degrees, in the center of which a tube is sealed through the foam housing, in the upper part of which is on the crosshead a water temperature sensor is installed, a second air temperature sensor is installed on the mast in a protective shield made of a hydrophobic heat-insulating material with a reflective coating and equipped with m lateral ventilation openings and the ball valve baroporta atmospheric pressure sensor is made of spheroplastic, air intake tube inlet is oriented downward and inside of the ball valve is a narrow channel, the upper surface of the valve abutment molded field similar diameter lockable channel.

The design differences of the device [5] from its analogues allow to achieve a technical result, which consists in increasing the reliability of measuring hydrometeorological parameters.

However, during long-term temporary studies in marine waters, especially in the conditions of the Arctic seas, the construction of the buoy’s hull, which includes plastic elements along with metal elements, is subject to deformation, which significantly reduces the life of the device. The appearance of deformation introduces additional errors in solving the problem of determining the wave parameters due to the presence of uneven movement of the buoy both in the vertical and horizontal planes, which also negatively affects the normal functioning of the satellite communication channel.

Also a significant disadvantage of the device [5] is its low autonomy, due to the life of the power source.

Similar disadvantages have known devices (patent RU No. 2238757 C2, 07/10/2008; patent RU No. 2254600 C1, 06/20/2005, US patent No. 42,20044 A1, 09/02/1980 [6-8]). When creating oceanographic instruments, the integration of various measuring instruments became widespread, which led to the fact that the autonomous buoys being created began to be intended not only for measuring waves, but also for obtaining information about the temperature of water and air, the speed and direction of currents, as well as other physical quantities.

The shape of the designed buoys should take into account the requirements for the buoy from the means of measuring these values. Therefore, some companies produce buoys that have not only a cylindrical, but also a different shape.

Abroad, various beacons with non-acoustic sensors are used to measure sea waves. Their main producers are the USA and Canada. In Canada, a series of compact, discharged from aircraft or surface ships, drifting CMOD (Compact Meteorogical and Oceanographic Drifter) generation beacons has been developed in Canada for measuring waves.

So “CMOD Waves” - a one-time drifting buoy - is designed to measure and calculate the characteristics of surface waves and transmit data through the integrated MAT 609 Argos PTT system and the NOAA Tiros satellite system. In addition to the standard CMOD generation sensors, the buoy uses accelerometers, tilt sensors and a compass device to determine the direction of the wavefront.

There is also known a device for measuring hydrometeorological parameters by means of registration placed on buoys, a device for measuring wave parameters (patent RU No. 2432589 10.27.2011 [9]), the essence of which is that in a device for measuring hydrometeorological parameters by means of registration placed on buoys [5], which consists of a hull, a mast with a device for transmitting information via radio and satellite communication channels, a wind parameter meter, atmospheric pressure meter with baroport m, including a separation chamber, a desiccant, a flexible connecting pipe, a lockable channel, an air collector, a ball valve located inside an air intake pipe, an air temperature sensor, a water temperature sensor, a beacon, a radar angle reflector, a control module with an optional GPS unit, an information memory unit, a central module with a controller, a wave height meter and a buoy orientation, a speed and direction sensor, salinity, electrical conductivity, turbidity sensors, content oxygen, the content of pH ions, a controller of oxidation / reduction processes, a power source in which the lower part of the housing is made in the form of a metal base equipped with a stabilizing device, a tube is sealed in the center of the housing, in the upper part of which a water temperature sensor is installed on the traverse, the second the air temperature sensor is mounted on the mast in a protective shield made of a hydrophobic heat-insulating material with a reflective coating and provided with side ventilation holes holes, and the ball valve of the baroport of the atmospheric pressure sensor is made of spherical plastic, the air intake tube is oriented downward and a narrow channel is located inside the valve above it, the upper surface of the valve fit is molded along the sphere of the same diameter of the lockable channel, the following additions are made: the body is made of all-metal, cigar-shaped forms, in the lower part of the housing is a retractable anchor device, a stabilizing device is installed on the upper part of the housing and but in the form of wings, articulated to the housing in the upper part by hinges, and at the bottom - by means of rubber shock absorbers in the upper housing portion also has elements of the parachute system, the power supply generator is provided, articulated to the stabilizing device.

The implementation of the stabilizing device in the form of wings and rubber shock absorbers in combination with a cigar-shaped body provides the repayment of unwanted hydrometeorological effects. The implementation of the all-metal housing allows you to use it repeatedly and eliminate the negative effects of both sea water and external conditions. The execution of the cigar-shaped body allows for uniform oscillations of the device when in the marine environment. The placement of the anchor device in the lower part of the housing helps to keep the buoy in a vertical position and reduces the influence of wind drift and drift from wave currents. The elimination of the negative impact on the device of sea water and external hydrometeorological conditions, as well as ensuring uniform fluctuations when it is in the marine environment, improves the accuracy of measuring hydrometeorological parameters. In addition, the shock absorbers connecting the wings of the stabilizing device with the lower part of the body are made in such a way that when the translational movement is made, the power source generator is started and the batteries of the power source are recharged, thereby increasing its useful life.

However, when operating the buoy at shallow depths with vertical rolling, it is necessary to ensure damping of the vertical rolling in the resonance region.

The introduction of satellite (navigation) technology, the equipment of wave-measuring buoys with satellite navigation receivers significantly reduces the time of determining the coordinates of the buoy and allows you to determine its motion elements with high accuracy.

It should be borne in mind that the concept of "satellite navigation technology" means the methods and techniques (algorithms) for using the results of measurements of radio navigation parameters (RNP) of signals from satellite navigation systems (SNA), obtained with the accuracy of both conventional and special satellite navigation receivers (SPS) to solve various applied problems. Depending on the required accuracy of navigation support, they can be divided into three groups:

- tasks provided by the regular navigation mode of the SNA;

- tasks provided by the differential mode of the SNA;

- tasks requiring relative positioning.

Regular navigation mode involves the use of measurement information only from the SNA. From code measurements (pseudo-ranges), usually form the coordinates of the object with the automatic exclusion of the systematic measurement error (discrepancy between the system time scale and the SOR scale). This error is a manifestation of the specifics of the non-query satellite navigation method (pseudo-rangefinder method) and is excluded by evaluating it in the extended coordinate vector. One of the simplest algorithms for solving the absolute positioning problem is the least squares method (Volosov PS, Dubinko Yu.S. et al. Shipborne satellite navigation systems. - L .: Sudostroenie, 1983. - 272 p.). The solution of the navigation problem at the same time implements the decomposition of the full state vector (coordinate and speed) into coordinate and speed subvectors and the full measurement vector (pseudorange and pseudo-speed) also into two subvectors: code and phase.

Consequently, estimates of the projections of the velocity vector are obtained from pseudo-Doppler measurements. The systematic error here is the rate of change of the divergence of time scales, caused mainly by the instability of the reference generator of the satellite navigation receiver (SPS).

The differential mode in the SPS involves the formation in the ground control and correction station (CCS), the coordinates of which are geodesically accurately linked to the terrain, corrections to the measured values of ranges caused by errors in predicting ephemeris information (EI), delays in the troposphere and ionosphere (for single-frequency SPS ), transferring them to consumers located in the area of the KKS operation within a radius of several tens to hundreds of kilometers, and taking these amendments into account in the SPS when solving the navigation problem.

However, both of these modes are neither functionally nor in terms of accuracy suitable for solving the determination of the parameters of the movement of a wave-like buoy with the required accuracy, as well as for solving problems of determining the inclination of the sea surface.

The task of creating a device, the design features of which will improve the accuracy of the measured hydrometeorological parameters, is solved in the well-known technical solution (patent RU No. 2490679 C1, 08/20/2013 [10]).

The well-known technical solution [10] is implemented by means of a buoy for determining the characteristics of sea wind waves, consisting of a body, a device for transmitting information via radio and satellite communication channels, a control module with an optional GPS unit, a power source, the body is made of an all-metal, cigar-shaped, in the lower parts of which a retractable anchor device is placed, the stabilizing device is installed on the upper part of the body and is made in the form of wings articulated with the body in the upper part ditch, and in the lower part of the casing - by means of rubber shock absorbers, in the upper part of the casing there are also elements of a parachute system, the power supply is equipped with a generator articulated with a stabilizing device, unlike the prototype the casing in its underwater part is equipped with a damping device consisting of a nozzle equipped with an even number of petals fixed to the buoy body using flat springs, with the odd petals fixed upward and the even petals fixed downward, an optional GP unit S contains a four-channel receiver of satellite signals with the possibility of simultaneous measurement of delta-range from up to four artificial Earth satellites, while the receiver of the satellite communication channel contains a navigation filter for simulating the movement of the buoy.

New distinctive features of the known technical solution, namely, that the buoy body in its underwater part is equipped with a damping device consisting of a nozzle equipped with an even number of petals secured to the buoy body using flat springs, the odd petals being fixed with an upward inclination, and the even the petals are fixed downward inclined; the optional GPS unit contains a four-channel receiver of satellite signals with the possibility of simultaneous measurement of deltap-range ranges of up to four artificial Earth satellites, while the satellite communication channel receiver contains a navigation filter, to simulate the movement of the buoy, when operating the buoy at shallow depths with vertical pitching, the damping of the pitching in the resonance region can be improved, measurement accuracy can be improved when solving problems of determining the motion parameters of the buoy and the incline of the sea surface .

However, the main drawbacks of the known buoy for determining the characteristics of sea wind waves [10] are measurement errors due to the periodicity of the satellite in the area of research, and errors due to the inability to separate the acceleration components caused on the one hand by the projections of gravity into three coordinate axes, and with on the other hand, components of acceleration of buoy movement in the horizontal plane.

The objective of the proposed technical solution is to increase the accuracy and reliability of the measurement of wave parameters through a buoy to determine the characteristics of sea wind waves.

The problem is solved due to the fact that the buoy for determining the characteristics of sea wind waves consists of a body, a device for transmitting information via radio and satellite communication channels, a control module with an optional GPS unit, a power source, the body is made all-metal, a retractable is located in the lower part of the body the anchor device, as well as the stabilizing device of the buoy, made in the form of wings, articulated with the hull by means of hinges and rubber shock absorbers, in the upper part of the hull there are parachute elements of the cradle system, the power source is equipped with a generator articulated with a stabilizing device, the buoy body in its underwater part is equipped with a damping device consisting of a nozzle equipped with an even number of petals secured to the buoy body using flat springs, with the odd petals secured upwardly, and even lobes are fixed with a downward inclination, the optional GPS unit contains a four-channel receiver of satellite signals with the possibility of simultaneous measurement of deltap-range ranges of up to four governmental satellites, wherein the satellite communication channel the receiver comprising a navigation filter for modeling the motion of the buoy. At the same time, the buoy for determining the characteristics of sea wind waves is made with a cross-sectional area along the waterline in a ratio of 2: 1 relative to the vertical dimension, the buoy for determining the characteristics of sea wind waves additionally contains a digital three-component accelerometer located in one housing with a three-component magnetometer.

The essence of the proposed technical solution is illustrated by the drawing, which shows a block diagram of a buoy for determining the characteristics of sea wind waves, which includes a control module 1 with an optional GPS unit, power supply 2, buoy body 3, retractable anchor device 4, stabilizing device 5, made in in the form of wings, hinges 6, rubber shock absorbers 7, mount unit for the parachute system 8, electrochemical breaker 9, timer 10, designed to start the power supply 2, micromotor 11 with gearbox 12, antenna 13 s GPS satellite communication channel, damping device 14, digital three-component accelerometer 15, located in one housing 16 with a three-component magnetometer 17.

The damping device 14, as in the prototype [10], consists of a nozzle equipped with an even number of petals secured to the buoy body using flat springs, the odd petals secured upwardly, and the even petals secured downwardly.

A buoy for determining the characteristics of sea wind waves is installed on the sea surface from an aircraft, as well as in the prototype, which allows to reduce the time to install many of these devices when performing large-scale studies, for example, during lengthy studies of processes at the atmosphere-ocean interface or during survey work in the construction of offshore hydraulic facilities, including offshore terminals of gas and oil fields. For installation from an aircraft, the device is equipped with a mount unit for the parachute system, through which the buoy is launched to the sea surface. The antenna 13 of the satellite communication channel of the GPS system is linearly polarized in the form of an asymmetric half-wave pin vibrator, which provides the best energy characteristics of radiation in the region of small angles, taking into account restrictions on the weight and size characteristics and operating conditions of the buoy.

To ensure the required probability of error-free reception of an information message from a buoy through a translator (spacecraft) to a ground-based receiving station of at least 0.99 in the conditions of interference fading of a transmitted signal, it is possible to generate packet messages containing a correction code block and a sync block consisting of a sync reamble for a spacecraft (translator) and synchro-preamble for a ground-based reception point, which determines the fact of receiving a packet, clock synchronization and sc GCC current bit-reception reliability. In addition, multiple transmission of packet messages with a duration not exceeding the average duration of time intervals favorable for reception was applied, with independent reception, majority addition of packets and restoration of the transmitted message by a buoy at a ground station.

To control the flooding of the antenna 13 by the sea wave and the shading of the spacecraft at small elevation angles and large notches, a control device 1 is provided that includes a current sensor in the circuit of the terminal stage of the power amplifier of the buoy transmitter with an amplitude modulator for two operating modes: high power mode "Used when transmitting a message, and the mode of" low power "used when waiting for favorable conditions for transmission. The stabilizing device, made in the form of wings 5, articulated with the lower part of the body using rubber shock absorbers 7, in combination with a cigar-shaped body provides the repayment of unwanted hydrometeorological effects. In addition, during hydrometeorological impacts on the buoy, the rubber shock absorbers 7 contract and stretch, making a translational motion. Making translational motion, the shock absorbers start the generator of the power source 2, which provides recharging the batteries of the power source 2. Anchor device 4 is designed to hold the buoy in an upright position and reduce the influence of wind drift and drift from wave currents. The execution of the housing 3 of the device all-metal allows you to use it repeatedly and exclude both the negative impact of sea water and the influence of external conditions, which are unstable in marine conditions.

The software for measuring wave parameters makes it possible to determine wave parameters (height, period, frequency, length, speed) with the allocation of the low-frequency part for describing large-scale oscillations of the sea surface, which is further used in the analysis of quasi-mirror reflection of radio waves by the Kirchhoff method and the high-frequency part for describing small-scale oscillations of the surface (wind ripple), which will be used later in the analysis of diffuse scattering of radio waves by the perturbation method. To dampen the pitching in the resonance region, the housing 3 is equipped with a damping device 14. The damping device 14, as in the prototype ([10], Fig. 2), consists of a nozzle equipped with an even number of petals fixed to the housing 3 of the buoy using flat springs moreover, the odd petals are fixed with an inclination up, and the even petals are fixed with an inclination down.

The damping device 14 is a nozzle mounted in the underwater part of the buoy on the housing 3. The damping element is the petals attached to the housing 3 of the buoy by means of flat springs. The damping device 14 has an even number of petals, with the odd petals secured upwardly, and the even ones downwardly secured.

With a vertical roll of the buoy, the petals will open, as a result of which the damping force will increase. A distinctive feature of the damping device 14 is that the magnitude of the resistance force, with vertical vibrations of the buoy, will depend on the frequency of these vibrations.

The digital three-component accelerometer 15 is an APXL 345 type digital accelerometer (interface 12 and SPI, measurement limits ± 2 g, ± 4 g, ± 8 g, ± 16 g, sampling frequency 0.1-3200 Hz). The digital three-component accelerometer 15 does not require external components, while accelerometers with an analog output are usually connected to the ADC through a low-pass filter (low-pass filter), and filter parameters must be calculated, and the error introduced by the filter elements must be calculated.

The optional GPS unit 1 contains a four-channel receiver of satellite signals with the possibility of simultaneous measurement of delta-range from up to four artificial Earth satellites, while the receiver of the satellite communication channel contains a navigation filter for modeling the movement of the buoy.

The determination of the current speed of the buoy on the signals of the SNA is carried out, as in the prototype.

If it is impossible to use a satellite channel to determine the parameters of sea wind waves, the average height and wave period are measured by the amplitude of the vertical roll of a surface buoy. The vertical component of the buoy roll is measured using a digital three-component accelerometer 15, combined in a single common housing 16 with a three-component magnetometer 17. Linear vertical displacements of the buoy are obtained by double integration of the vertical acceleration component over time. When processing data, the contribution of the projection of gravity onto the vertical axis due to the inclination of the buoy along the two horizontal axes X and Y is excluded.

At the same time, the buoy tilts along the X and Y axes are measured independently of the accelerometer 15 by processing the magnetometer 17 data. Independent measurements of the buoy tilt angles allow to exclude errors in the measurement of wave height due to the horizontal component of the buoy roll.

In known buoy designs, a one-component analog accelerometer, stabilized vertically by means of a pendulum suspension in a cardan with a vibration damper with an oil damper, is used to determine the waves. A pendulum with a relatively short period of natural oscillations with respect to the wave period ensures the verticality of the acceleration sensor when the buoy is inclined, which is necessary for the correct measurement of the vertical component of acceleration. In reality, the buoy does not oscillate strictly vertically, but has periodic horizontal displacements due to sliding along the inclined wave front. Due to the horizontal component of the buoy oscillations, horizontal accelerations appear that deflect the pendulum suspension vertically and, as a result, cause a proportional error in the measurement of the vertical component of acceleration. This type of error in measuring the wave height is fundamentally unrecoverable if we rely only on measurements of three projections of acceleration recorded by the accelerometer. Errors are due to the inability to separate the components of the acceleration caused on the one hand by the projections of gravity into three coordinate axes, and on the other, the components of the acceleration of the sensor.

For the correct solution of the problem, it is required to additionally involve the data of an independent tilt angle sensor. In necessary cases, gyroscopes or magnetometers based on the stable angular direction of the Earth's magnetic tension vector are used for accurate measurements.

It is assumed that regardless of the presence or absence of the horizontal component of the buoy rolling, the vertical amplitude of the oscillations accurately tracks the height of the water surface. The buoy, made in the form of a structure with a large cross-sectional area along the waterline relative to its dimensions, maintains the position of the waterline both on the crests and on the troughs of the waves with an error of the order of 10 cm, which characterizes the possible errors in measuring the wave height.

The task of processing the wave data is to build wave points from the points during the observation interval, followed by calculating the average height and wave period. According to statistical standards, to process data on waves, it is enough to have a series of observations of 30 waves with an average period of 6 s, which is an averaging interval of 180 s. Sufficient discreteness of the waveogram samples is 0.5 s, which corresponds to measuring wave periods from 2 to 12 s. Each sample should represent an average value in the range of 0.5 s in order to filter high-frequency components. A series of observations from 360 samples should be centered, i.e. a constant component should be excluded from it. Only the vertical component of the acceleration is accepted for processing, from which the projections of gravity due to the buoy's inclinations are excluded.

First, the data of the magnetometer 17 are measured and processed to measure the angles of inclination of the Z axis from the vertical at each point of the waveform with a period of 0.5 s in the interval of 180 s (360 counts in total).

For this, all three components of the magnetic field M _x , M _y , M _z with a frequency of 100 Hz are recorded, 50 samples are averaged and written to the buffer memory. At each point of the waveogram with a number from 1 to 360, the instantaneous angle of deviation of the magnetic field vector from the Z axis of the sensor is calculated by the formula:

,

,

where M _x , M _y , M _z are the values of the magnetic field projections averaged over 50 measurements on the X, Y, Z axis in arbitrary units. The price of divisions along the axes should be reduced to a single scale by preliminary calibration (by determining the scale factors m _x , m _y , m _z ).

The obtained value of α _{z is} still insufficient to calculate the angle of deviation of the Z axis from the vertical, since the magnetic field vector M is inclined to the horizontal by some angle β, depending on the coordinates of the geographic point and called magnetic inclination (in contrast to magnetic declination, the angle between the geographic and magnetic meridian ) The magnetic inclination is calculated as the average value of the angle α _{z of the} entire series of observations from 360 points, based on the assumption that the buoy oscillations occur symmetrically relative to the vertical. In calm weather without disturbance, the magnetic inclination is equal to the angle α _z .

At each point of the waveform from 1 to 360, the deviation of the Z axis of the sensor from the vertical is calculated by the formula:

γ = α _z -β, where

γ is the angle of deviation of the Z axis from the vertical, in radians;

α _z is the instantaneous angle of the Z axis relative to the magnetic field vector;

β is the magnetic inclination.

Three acceleration components are recorded along the X, Y, Z axes at each point of the waveform from 1 to 360 with a frequency of 100 Hz, averaged over 50 samples, are recorded in buffer memory in arbitrary units. Then the acceleration readings are converted into a physical quantity m / s ² by multiplying by the graduated coefficients a _x , a _y , a _z determined during the initial calibration of the sensor. This is necessary in order to obtain the wave height in meters in subsequent calculations. The obtained three series of observations are centered, calculating the average value from 360 samples and subtracting the obtained average value from each sample. On the Z axis, the average acceleration should be close to 9.8 m / s ² , and on the horizontal components X and Y - close to zero. If this condition is met, then the buoy does not have a constant component of the angle of inclination. If not performed, then subsequent processing using magnetometer data, the error from the angle of inclination will be eliminated. The data of the magnetometer 17, measuring the angles of inclination of the buoy from the vertical, are necessary if oscillations in the angle occur symmetrically with respect to the vertical. If we imagine that under the influence of wind or other reasons, the buoy oscillates only in the angle of inclination, without experiencing vertical movements of the center of gravity, then the result of measuring the height of the waves should be zero. However, the projection of gravity on the Z axis will have a significant amplitude when taking into account the tilt angles, which will give a false amplitude of the vertical roll. To avoid this kind of error, all three projections on the X, Y, Z axis should be taken into account, which with vector addition will give an acceleration value of exactly 9.81 m / s ² , which indicates the absence of excitement.

To calculate only the vertical component of the buoy roll, it is enough to project the registered acceleration projections b _x , b _y , b _z onto the vertical. For this, it is necessary to use the angle of inclination γ of the Z axis to the vertical, measured by a magnetometer 17. Calculations are performed for each point of the waveogram according to the formula:

B = b _z * cosγ + b _X * cos (γ + 90 °) + b _Y cos (γ + 90 °), where

B is the vertical component of the acceleration of the buoy in m / s ² ;

b _x , b _y , b _z — acceleration components measured by the accelerometer at each point of the waveform, m / s ² ;

γ is the angle of deviation of the Z axis of the sensor from the vertical at each point of the waveform.

As a result of the calculations, we obtain a centered series of 360 points of vertical accelerations of the buoy, which is used later to calculate the height and period of the wave.

Next, integrate acceleration.

The first integration of a series of observations over time gives the instantaneous speed of the vertical movement of the buoy at each point of the waveform. The increment of speed is calculated by the formula known from physics:

ΔV = g * Δt, where

ΔV is the increment of speed in m / s,

g - acceleration in m / s ² ,

Δt is the sampling interval in s.

Integration is performed in steps from the first point of the waveform to 360, sequentially adding a speed increment taking into account the sign from point to point according to the formulas:

V ₁ = B ₁ ∗ Δt

V ₂ = (B ₁ + B ₂ ) * Δt

V ₃ = (B ₁ + B ₂ + B ₃ ) * Δt

V _n = (B ₁ + B ₂ + B ₃ + B _n ) * Δt, where

V ₁ ... V _n - buoy speed at the points of the waveform from 1 to 360 in m / s;

B ₁ ... B _n - vertical acceleration of the buoy at the points of the waveform;

Δt = 0.5 s is the quantization resolution in s.

Correction of the zero point of the acceleration sensor is not required, since the original row was centered.

The resulting new series of instantaneous buoy velocities from 360 samples is subjected to second integration, as a result of which the desired waveform of wave height is obtained directly in meters. The calculations are performed according to a similar formula:

H ₁ = V ₁ ∗ Δt

H ₂ = (V ₁ + V ₂ ) * Δt

H ₃ = (V ₁ + V ₂ + V ₃ ) * Δt

H _n = (V ₁ + V ₂ + V ₃ + V _n ) * Δt, where

H is the vertical displacement of the buoy in m;

V ₁ , V ₂ ... V _n - buoy speed at the points of the waveform from 1 to 360;

Δt = 0.5 s is the quantization resolution.

The average wave height from the bottom to the top is calculated, assuming that the buoy oscillates in a sinusoidal manner. In fact, the area of the waveogram is calculated, divided by the time of observation and multiplication by the shape factor. The shape factor can be adjusted according to the results of field tests of the wave sensor. The calculation is performed according to the formula:

, где

where

H _cf - wave height in m;

H ₁ , N ₂ ... N ₃₆₀ - the displacement of the buoy from its average position in absolute value (unsigned) in m;

K = 1.41 - shape factor for a sinusoid.

The average wave period is determined by the formula by the ratio of the amplitudes of the wave height and accelerations, based on the assumption of a sinusoidal wave form. The calculation is performed according to the formula:

, где

where

T is the average period of the wave, s;

In _cf is the average acceleration amplitude, m / s ² ;

N _cf - average wave height, m

It should be noted that the average period of excitement calculated using this formula is rather arbitrary, but it corresponds to the period of a sinusoid with the maximum amplitude obtained by Fourier spectral analysis - decomposition. Previously, when processing waveograms, the average wave period was determined by the number of intersections of the waveogram with zero sea level. At small wave amplitudes between trains of relatively large waves, the number of zero-level intersections increases sharply and is difficult to calculate. The conventionality of this approach to measuring the period of excitement is even more formal and does not reflect the energetic side of the process. There is no strict definition of the average period of unrest.

The real parameters of the waves are determined based on the following equations.

If the buoy makes sinusoidal oscillations on the wave, then the equations of motion are written as follows:

H = H ₀ * sinωt

V = ωН ₀ * sinωt

g = ω ² * H ₀ * sinωt, where

;

;

H ₀ is half the wave height in m;

V is the instantaneous speed of the buoy in m / s;

g is the instantaneous acceleration in m / s ² ;

ω is the angular frequency of the waves, 1 / s;

T is the wave period, s;

t - current time in sec.

From these formulas, the expression for the wave period is derived depending on the ratio of the wave amplitude and acceleration amplitude (or their average values):

.

.

If we substitute in these formulas the real wave height of 5 m, the oscillation period of 10 s, then we obtain the acceleration amplitude of the buoy:

, где

where

,

,

H ₀ = 1/2 * 5 m;

g = 0.985 m / s ² , i.e. about 0.1 m / s ² , and the ratio g / H ₀ will be 0.1 / 2.5 = 0.392.

The average height and the period of excitement in the proposed technical solution are measured by the amplitude of the vertical roll of the anchored surface buoy. The vertical rolling component of the anchored surface buoy is measured using a digital three-component accelerometer 15, combined in one common housing 16 with a three-component magnetometer 17. The linear displacement of the buoy vertically is obtained by double integration of the vertical acceleration component over time. When processing data, the contribution of the projection of gravity onto the vertical axis due to the inclination of the buoy along the two horizontal axes X and Y is excluded.

At the same time, the buoy tilts along the X and Y axes are measured independently of the accelerometer 15 by processing the magnetometer 17 data. Independent measurements of the buoy tilt angles allow to exclude errors in the measurement of wave height due to the horizontal component of the buoy roll.

And while determining the characteristics of wind waves through the use of an accelerometer and a magnetometer and a satellite channel, the root-mean-square error of the range increment by the Doppler method which does not depend on the duration of the integration interval and on dividing this interval into parts, provides increased reliability and reliability in determining the characteristics of wind waves. The latter circumstance allows for continuous measurements of delta-range-to-four satellites, eliminating the systematic error of the frequency standard of the buoy receiving device, to build the trajectory of its movement, regardless of its dynamics.

, где V - скорость движения волны, определяемая по изменению доплеровской частоты в горизонтальной плоскости, g - ускорение силы тяжести, Y_в - коэффициент, зависящий от плотности воды), которые используют для прогноза воздействия волнения на морские объекты хозяйственной деятельности, например добычные комплексы и морские терминалы по отгрузке углеводородов.Other wave parameters (phase velocity c, wavelength L, group velocity c _g , wave steepness (H ₀ / L ₀ ) _max ) are calculated on the basis of known formula dependences depending on the sea depth in the measurement area (shallow water, intermediate, deep water), as well as characteristics such as wave energy (E = e / 8hL, where e is the weight of 1 m of sea water in kg; h is the wave height in m; L is the wavelength in m), the height of the wave (formula H . I. Dzhunkovsky: hв = 3.2 khtga, where h is the wave height in m; k is the slope roughness coefficient, k = 1 for smooth slopes, k = 0.9 for paved and single slopes, k = 0.77 for stone sketches and continuous thickets on the slope; α is the angle of inclination of the slope to the horizon); wave impact force ( $$P={\stackrel{2}{Y}}_{\mathrm{at}}V/g$$

, where V is the velocity of the wave, determined by the change in the Doppler frequency in the horizontal plane, g is the acceleration of gravity, Y _in is a coefficient depending on the density of water), which are used to predict the impact of the waves on marine objects of economic activity, for example, mining complexes and offshore hydrocarbon shipping terminals.

Industrial implementation of the claimed technical solution can be carried out by using commercially available measuring sensors, components and elements, which allows us to conclude that the claimed technical solution meets the patentability condition “industrial applicability”.

Thus, the new distinguishing features of the claimed invention ensure the achievement of the technical result, which consists in increasing the accuracy and reliability of the measurement of wave parameters by means of a buoy for determining the characteristics of sea wind waves.

Information sources

1. Copyright certificate SU No. 1280321, 12/30/1986.

2. Copyright certificate SU No. 1280320, 12.30.1986.

3. Patent SU No. 1712784, 02.15.1992.

4. JP patent No. 60107490, 06/12/1985.

5. Patent RU No. 23228757, 07/10/2008.

6. Patent RU No. 2238757 C2, 07/10/2008.

7. Patent RU No. 2254600 C1, 06/20/2005.

8. US patent No. 422,044 A1, 02.09.1980.

9. Patent RU No. 2432589, 10.27.2011.

10. Patent RU No. 2490679 C1, 08/20/2013.

Claims (1)

     Buoy for determining the characteristics of sea wind waves, consisting of a body, an information transmission device via radio and satellite communication channels, a control module with an optional GPS unit, a power source, the body is made of all-metal, a retractable anchor device and a stabilizing device are located in the lower part of the body buoy made in the form of wings articulated with the hull by means of hinges and rubber shock absorbers, elements of the parachute system are placed in the upper part of the hull, the power source is equipped with a gene a rotor articulated with a stabilizing device, the buoy body in its underwater part is equipped with a damping device consisting of a nozzle equipped with an even number of petals secured to the buoy body using flat springs, the odd petals secured upward and the even petals secured downward , the optional GPS unit contains a four-channel receiver of satellite signals with the possibility of simultaneous measurement of deltap-range to four artificial satellites of the Earth, while the receiver with the communication channel contains a navigation filter for modeling the movement of the buoy, characterized in that the buoy for determining the characteristics of sea wind waves is made with a cross-sectional area along the waterline in a ratio of 2: 1 relative to the vertical dimension, the buoy for determining the characteristics of sea wind waves additionally contains a digital three-component accelerometer, housed in one housing with a three-component magnetometer.