RU2490679C1 - Buoy for determining characteristics of sea waves - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: device consists of a housing (3), a device for transmitting information over radio and satellite communication channels (13), a control module (1) with an optional GPS unit, a power supply (2). The housing (3) is entirely made of metal and is cigar-shaped. In the lower part of the housing (3) there is pull-out anchor apparatus (4) and in the upper part there is a stabilising device (5) in form of wings. There are also elements of a parachute system (8) in the upper part of the housing (3). Furthermore, the housing (3), in its submerged part, is equipped with a damping device (14) which consists of an orifice equipped with an even number of lobes. Said lobes are attached to the housing of the buoy by flat springs. Even lobes are attached with inclination downwards and odd lobes are attached with inclination upwards. The optional GPS unit has a four-channel satellite signal receiver which is able to simultaneously measure delta-pseudoranges to four artificial Earth satellites. The satellite communication channel receiver has a navigation filter for simulating movement of the buoy.

EFFECT: determining characteristics of sea waves.

3 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 1280321, 12/30/1986; copyright certificate SU 1280320, 12/30/1986; copyright certificate SU 1712784, 02/15/1992; patent JP 60107490, 06/12/19S5 [1 -4]), consist of a hull, a mast with a device for transmitting information via radio and satellite channels, a wind parameter meter, an atmospheric pressure meter, an air temperature sensor, a water temperature sensor, a beacon, a radar corner reflector, and 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, oxygen content, pH ions, an oxidation / reduction controller, a source nutrition.

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.

A device is also known for measuring hydrometeorological parameters by means of registration placed on buoys (patent RU 2328757, July 10, 2008) [5], which consists of a cylindrical body, a mast with a device for transmitting information via radio and satellite communication channels, a wind parameter meter, 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, a sensor air temperature, water temperature sensor, beacon, radar corner reflector, control module with optional GPS unit, information memory unit, central module with controller, wave height and orientation meter, speed and direction sensor, salinity, 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 tmass, 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 extending 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 a side ventilation holes, and the baroport ball valve of the atmospheric pressure sensor is made of spherical plastic, the intake pipe is oriented downward by the inlet and inside it is a narrow channel above the ball valve, the upper surface of the valve fit is molded along the sphere of the same diameter of the 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.

The known devices also have similar disadvantages (patent RU No. 2238757С2 July 10, 2008; patent RU No. 2254600С1 June 20, 2005, US patent No. 42,20044A1 of September 2, 1980 [6-8]. When creating oceanographic instruments, the combination of various measuring instruments was widespread, this 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.

The closest analogue (prototype) of the claimed invention is a device for measuring hydrometeorological parameters by means of registration placed on buoys is a device for measuring wave parameters (patent RU No. 2432589 10.27.2011 [9]), the essence of which is that the device for measure 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, measure For a wind parameter, atmospheric pressure meter with a pressure port 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, and 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, a sensor for determining salinity, electrical conductivity, turbidity, oxygen content, pH ion content, oxidation / reduction process controller, power source, in which the lower part of the body is made in the form of a metal base equipped with a stabilizing device, a tube is sealed in the center of the body, in the upper part of which a water temperature sensor is installed on the traverse, a second air temperature sensor is installed on the mast in a protective shield made of hydrophobic heat-insulating material with a chewing coating and provided with lateral ventilation openings, and the atmospheric pressure sensor’s baroport ball valve is made of spherical plastic, the air intake pipe is oriented downward and a narrow channel is located inside it above the ball valve, 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 casing is made of all-metal, cigar-shaped, in the lower part of the casing there is a retractable anchor device, stabilization uyuschee device is mounted on top of the housing and is in the form of wings, articulated to the housing in the upper part by hinges, and in the lower part by means of rubber shock absorbers in the upper housing portion also has elements of the parachute system, the power supply is provided with a generator, 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 the buoy operates 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 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) for solving 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. Ship satellite navigation systems. - L .: Sudostroenie, 1983. - 272 p.):

$$\Delta X=(H^T{H}^{-\mathrm{one}})H^{T}L,\text{(one)}$$

where ΔX is the vector of corrections to reckoning coordinates, i.e. to the coordinates of the point relative to which the linearization of the measurement equations is made;

L is the vector of the differences of the measured and calculated values of the navigation parameters;

(здесь индекс i соотносит переменные с оцениваемыми параметрами, j - с номерами спутников).H - pseudorange partial derivatives matrix with respect to estimated parameters $$H=\left|\left|h_{ji}\right|\right|$$

(here index i correlates variables with estimated parameters, j - with satellite numbers).

Elements of the matrix h _ji (i = 1, 2, 3) represent the direction cosines of the line of sight of the satellites, and for i = 4 h _ji = 1.

Solving the navigation problem by formula (1) 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.

при этом изменений не претерпевает.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). Matrix $$\left|\left|h_{ji}\right|\right|$$

at the same time does not undergo changes.

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 problem to which the claimed invention is directed is to create a device whose design features will improve the accuracy of the measured hydrometeorological parameters.

The problem is solved due to the fact that in the buoy for determining the characteristics of sea wind waves, consisting of a housing, a device for transmitting information via radio and satellite channels, a control module with an optional GPS unit, a power source, the housing is made of 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 by means of hinges, and in the lower parts of the hull by means of rubber shock absorbers, parachute system elements are also located in the upper part of the hull, the power supply is equipped with a generator coupled to a stabilizing device, unlike the prototype, the hull in its underwater part is equipped with a damping device consisting of a nozzle equipped with an even number of petals, fixed to the body of the buoy using flat springs, with the odd petals secured upwardly, and the even petals secured downward inclined, the optional GPS unit contains a three-channel receiver of satellite signals with the possibility of simultaneous measurement of delta-range ranges of 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.

New distinctive features of the proposed technical solution, which consists in the fact 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 fixed 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 to four artificial x of the Earth’s satellites, while the receiver of the satellite communication channel contains a navigation filter, to simulate the movement of the buoy, when the buoy operates at shallow depths during vertical roll, damping of the vertical roll in the resonance region, improve measurement accuracy in solving problems of determining the parameters of the movement of the buoy, and slopes of the sea surface.

The essence of the proposed technical solution is illustrated by drawings.

Figure 1. 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, a power source 2, a buoy body 3, a retractable anchor device 4, a stabilizing device 5 made in the form of wings, 6 - hinges, 7 - rubber shock absorbers, 8 - attachment point of the parachute system, 9 - electrochemical disconnector, 10 - timer designed to start the power supply 2, 11 - micromotor with gear 12, 13 - antenna of the satellite communication channel of the GPS system, damping device 14.

Figure 2. Damping device design. The damping device 14 consists of a nozzle 15 provided with an even number of petals 16, fixed to the housing 3 of the buoy using flat springs 17, the odd petals are fixed with an inclination upward, and the even petals are fixed with an inclination downward.

Figure 3. The scheme for determining the motion parameters of a given point of the buoy. Case 3 buoys, antenna 13 of the GPS satellite communication channel.

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 reduces the time to install many of these devices when performing large-scale studies, for example, during long-term studies of processes at the interface between the atmosphere and the ocean or during survey work in the construction of offshore hydraulic facilities, including offshore 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 that provides the best energy characteristics of radiation in the field 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.

An estimate of the probability of error-free reception of a 500-bit buoy message taking into account the simulation of the channel transmission coefficient, the operating range of the spacecraft elevation angles and waves at a wind speed of 6 to 10 m / s depending on the radio emission power for code structures differing in a corrective code and transmission ratio batch messages for majority processing and the presence or absence of alternation of symbols of the correction code showed that to achieve the requirements of reliability of reception in the range of spacecraft elevation angles of 15-45 degrees and packet transmission ratio of 5, the longest message transmission time of 21.6 s is achieved using the most effective BCH correction code, and the smallest time of 9.4 s is achieved when using a simple Kasahara code having the highest relative bit rate; the minimum radio emission power, equal to 3.5 W, is achieved using the correcting BCH code, and the highest, equal to 29 W, is achieved using a simple BCH code.

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 us 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 execution of the casing 3 of the cigar-shaped device allows for uniform oscillation of the device when in sea water.

As the case of the device for measuring hydrometeorological parameters, the bodies of commercially available marine signal buoys can be used, which can significantly reduce the cost of manufacturing the buoy.

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 sea surface (wind ripple), which will be used later in the analysis of diffuse scattering of radio waves by the perturbation method. Unlike the prototype [9], in the proposed technical solution, for damping the pitching in the resonance region, the housing 3 is equipped with a damping device 14. The damping device 14 consists of a nozzle 15 provided with an even number of petals 16 fixed to the housing 3 of the buoy using flat springs 17, wherein the odd petals are fixed with an inclination upward, and the even petals are fixed with an inclination downward (FIG. 2).

The damping device 14 is a nozzle 15 mounted in the underwater part of the buoy on the housing 3. The damping element is the petals 16, fixed to the housing 3 of the buoy by means of flat springs 17. The damping device 14 has an even number of petals, the odd petals are fixed with an inclination upward, and even with a downward slope.

In the vertical roll of the buoy, the petals 16 will open, resulting in an increase in damping force. A 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.

In contrast to the prototype [9], 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.

и вращается вокруг мгновенного центра качаний с угловой скоростью $$\overline{{\omega }_k}$$

. Линейная скорость точек А и N в условиях сложного движения обозначена векторами $${\overline{V}}_A$$

и $${\overline{V}}_N$$

. Положение точек А, N и М относительно центра Земли обозначено векторами $${\overline{R}}_A$$

,

и $${\overline{R}}_N$$

. Точки А и N фиксированы относительно корпуса буя, а положение точки М в процессе динамического движения непрерывно меняется. Векторы $$\overline{RA}$$

и $$\overline{VA}$$

определяются координатами и составляющими скорости точки А, вырабатываемыми СНП. Пренебрегая в данном случае нежесткостью несущих конструкций антенного устройства СНП и корпуса самого буя, на основании известного выражения для вектора скорости твердого тела при сложном движении (Ривкин С.С. Определение линейных скоростей и ускорений качки корабля инерциальным методом. - Л..: ЦНИИ «Рубин», 1980. - 180 с.) следует, что:Determining the current buoy speed from the SNA signals is a rather complicated task, the feature of which is that by the SNA signals it is possible to measure the coordinates of the point of the buoy combined with the phase center of the antenna (FCA) of the satellite navigation equipment installed on the buoy. This point is involved in complex translational and rotational motion. The task of determining the parameters of the movement of the buoy can be represented as follows. Let a buoy (Fig. 3) with a swing center M arbitrarily given by a point N and a fixed point A combined with a PCA participate in translational motion with linear velocity $$\overline{V}$$

and revolves around the instantaneous swing center with angular velocity $$\overline{{\omega }_k}$$

. The linear velocity of points A and N under complex motion is indicated by vectors $${\overline{V}}_A$$

and $${\overline{V}}_N$$

. The position of points A, N and M relative to the center of the Earth is indicated by vectors $${\overline{R}}_A$$

,

and $${\overline{R}}_N$$

. Points A and N are fixed relative to the body of the buoy, and the position of point M in the process of dynamic movement is constantly changing. Vectors $$\overline{RA}$$

and $$\overline{VA}$$

are determined by the coordinates and components of the speed of point A generated by the SPS. In this case, neglecting the rigidity of the supporting structures of the antenna device of the SPS and the body of the buoy itself, on the basis of the well-known expression for the velocity vector of a solid body with complex motion (Rivkin S.S. Rubin ", 1980. - 180 p.) It follows that:

$${\overline{V}}_A={\overline{V}}_M+{\overline{r}}_k{\overline{\omega }}_k\overline{V_N}={\overline{V}}_M+{\overline{\omega }}_k{\overline{r}}_N.\left(2\right)$$

; $${\overline{V}}_M={\overline{V}}_N-{\overline{\omega }}_k{\overline{r}}_N.\left(3\right)$$

The speed of point M, the position of which varies indefinitely, is expressed in the form of differences: $${\overline{V}}_M={\overline{V}}_A-{\overline{\omega }}_k{\overline{R}}_A$$

; $${\overline{V}}_M={\overline{V}}_N-{\overline{\omega }}_k{\overline{r}}_N.\left(3\right)$$

From this expression, we obtain the value for the velocity vector of the given point of the buoy:

. $${\overline{V}}_N={\overline{V}}_A+{\overline{\omega }}_k\left({\overline{r}}_N-{\overline{r}}_A\right)={\overline{V}}_A+{\overline{\omega }}_k{\overline{r}}_N.\left(\mathrm{four}\right)$$

.

Since expressions (3) and (4) are free of motion parameters and the position of the instantaneous swing center M, they can be used to recalculate the information measured by the SNA signals at a given point.

необходимо знать относительное положение заданной точки и антенны $$\left({\overline{r}}_k\right)$$

, а также угловую скорость вращения корпуса буя $$\left({\overline{\omega }}_k\right)$$

. Решение данного вопроса возможно посредством описания положения точки М через А и N: $${\overline{R}}_M={\overline{R}}_A-{\overline{r}}_A$$

; $${\overline{R}}_M={\overline{R}}_N-{\overline{r}}_N\left(5\right)$$

.From the expression (2) it follows that to determine the velocity vector of a given buoy point according to the SNA in addition to $${\overline{V}}_A$$

you need to know the relative position of a given point and antenna $$\left({\overline{r}}_k\right)$$

as well as the angular speed of rotation of the buoy body $$\left({\overline{\omega }}_k\right)$$

. The solution to this issue is possible by describing the position of point M through A and N: $${\overline{R}}_M={\overline{R}}_A-{\overline{r}}_A$$

; $${\overline{R}}_M={\overline{R}}_N-{\overline{r}}_N\left(5\right)$$

.

.From formula (5) we obtain an expression that determines the position of a given point of the buoy: $${\overline{R}}_N={\overline{R}}_A-{\overline{r}}_A+{\overline{r}}_N={\overline{R}}_A-{\overline{r}}_A.\left(6\right)$$

.

Since expressions (2) and (3) are free of motion parameters and the position of the instantaneous swing center M, they can be used to recalculate the information measured by the SNA signals at a given point.

Representing expressions (2) and (3) in projections on the axis of a topocentric coordinate system with a beginning at point A, we obtain: $$\begin{array}{l}{V}_{NX}=V_{AX}+{\omega }_{ky}{r}_x-{\omega }_{kx}{r}_y;R_{NX}=R_{AX}-r_x=-r_x;\\ V_{Ny}=V_{Ay}+{\omega }_{kx}{r}_x-{\omega }_{kx}{r}_x;R_{Ny}=R_{Ay}-r_y=-r_y;\\ V_{NX}=V_{AX}+{\omega }_{kx}{r}_y-{\omega }_{ky}{r}_x;R_{NX}=R_{AX}-r_x;\end{array}\}\left(7\right)$$

The methodology for calculating the motion parameters of a marine object under irregular rolling conditions was developed in detail in (Rivkin S. S. Determination of linear velocities and accelerations of the ship’s rolling by the inertial method. - L ..: Central Research Institute “Rubin”, 1980. - 180 p. Networked satellite radio navigation systems / BC Shibshevich, P.P. Dmitriev, N.V. Ivantsevich et al. - M.: Radio and communications, 1982 - 272 p.) And allows you to calculate the statistical characteristics of the errors of navigation definitions from the SNA signals.

In order to exclude the influence of the distance of points A and N on the accuracy of determining the components of the velocity vector of a given point of a buoy, in the general case, it is necessary to take into account the corresponding terms in the right-hand sides of equations (7). In the specific case, due to the small dimensions of the buoy, these values can be neglected.

Given the small dimensions of the buoy and the equal ratios of the magnitude of the antenna, it is advisable to determine the coordinates of the place and the components of the speed of its movement using quasidaleric or quasi-Doppler measurements. The use of simultaneous measurements of range and radial velocity makes it possible to determine not only the coordinates, but also the components of the buoy speed from such a sample. To find all unknown parameters, it is not necessary to solve the system of equations, since using the decomposition method under certain conditions, we can simplify the problem and pass to the independent solution of two equations giving, respectively, the coordinates and components of the buoy velocity vector. The condition for applying the decomposition is the absence of responses of the measured quantities to changes in some of the determined parameters. It is known that in simultaneous measurements, the velocity components are determined only by Doppler measurements. At the same time, for the orbits of the navigation satellites of the GLONASS system, we can assume that Doppler measurements respond poorly to changes in coordinates, as a result of which the coordinates are determined almost exclusively from quasi-one-dimensional measurements. Therefore, without loss of accuracy, the processing of rangefinder-Doppler measurements can be performed in two stages. At the first stage, the components of its speed are estimated based on the results of quasi-Doppler (difference-Doppler) measurements. At the first stage, ranging, difference-ranging and quasi-ranging algorithms can be used (On-board devices of satellite radio navigation / N.V. Kudryavtsev, I.I. Mishchenko, A.I. Volynkin, etc. - M .: Transport, 1988 - 201 s )

At the second stage, the estimation of the components of the wave-buoy velocity is reduced to solving the following equations:

- with Doppler measurements $$R_i=\stackrel{-\mathrm{one}}{r_i}\left[\left(x_{ci}-x\right)\left(x_{ci}-x\right)+\left(y_{ci}-y\right)\left(y_{ci}-y\right)+\left(z_{ci}-z\right)\left(z_{ci}-z\right)\right],i=\mathrm{one,}23\left(8\right)$$

- with difference-Doppler measurements $$\Delta r_{jl}=r_j-r_l,i=23\mathrm{four}\left(9\right)$$

with quasi-Doppler measurements $$r_{jl}=r_j+\delta r_f\left(10\right)$$

where δr _f is the correction of the radial velocity due to the discrepancy between the frequencies of the generators of the receiver of the buoy and satellite.

The systems of equations (8-10) with respect to the component velocities x, y, z are linear, and methods for solving them are obvious.

In a specific implementation of the claimed technical solution, since the pseudorange measurements of up to four satellites are performed by a four-channel receiver, the following algorithm is applied:

$${\displaystyle \sum _{J=\mathrm{one}}^3{\left(x_{cy}-x_j\right)}^2={\left(r_i-\tau \right)}^2\left(\mathrm{eleven}\right)}$$

.

Moreover, the measured pseudorange can be attributed to a single point in time, so a single notch of four pseudorange allows you to fix the instantaneous spatial position of the buoy. The accuracy of determining the instantaneous coordinates does not depend on the dynamics of the buoy, nevertheless, the refinement of these coordinates due to smoothing out quickly fluctuating measurement errors can be carried out only if there is information about the nature of the trajectory of the buoy, allowing the calculation of its coordinates in the intervals between pseudorange measurements. Knowledge of the trajectory of the buoy (its dynamics) is necessary to develop the current values of such important navigation parameters as the components of its velocity vector in a specific implementation of the proposed technical solution, such information can be obtained using a mathematical model that describes the dynamics of the buoy. For this, a navigation filter is used in the receiver to simulate the movement of the buoy. A discrete Kalman filter was used as such a filter (Zaitsev A.V., Reznichenko V.I. Determination of the ship's ship speed from the signals of the medium-orbit space navigation system // Notes on Hydrography. - 1982 - No. 208a. - p. 62-64), which is built on the basis of the following models of buoy dynamics and measurements:

$$X_k=F_{k-\mathrm{one}}{X}_{k-\mathrm{one}}+A_{k-\mathrm{one}}{W}_{k-\mathrm{one}}\left(12\right)$$

$$Z_k=H_k{X}_k+U_{k-\mathrm{one}}\left(13\right)$$

where X _k is the state vector;

Ф _k - transition matrix;

H _k - matrix of partial derivatives of measurements;

Z _k is the vector of measurements;

W _k is the disturbance (noise) vector of the buoy dynamics;

U _k is the vector of measurement noise.

The movement of the buoy is modeled by a dynamic system excited by noise. The variables of the differential equations describing this system form the state vector X _k . In addition to these variables, some “interfering” parameters are modeled in the filter - systematic errors of measurements of pseudorange and pseudo-velocity, which are also included in the state vector.

. Дисперсия этой суммы: $${\delta }_{\Sigma }^2={\displaystyle \sum _{I=0}^n{\displaystyle \sum _{j=0}^{n}E\left[{\epsilon }_i-{\epsilon }_j\right].\left(14\right)}}$$

.For a buoy, in addition to pseudorange, the delta pseudorange, which essentially represents the results of integrating the Doppler frequency shift over a finite interval Δt = t _i + 1-t _i , is included in the measurement vector Z. If we add up to the delta-pseudorange range t _n -t ₀ , obtained by integrating the Doppler frequency with an error ε _i at successive times t _i we obtain a range increment in the interval with an error

. The variance of this amount: $${\delta }_{\Sigma }^2={\displaystyle \sum _{I=0}^n{\displaystyle \sum _{j=0}^{n}E\left[{\epsilon }_i-{\epsilon }_j\right].\left(\mathrm{fourteen}\right)}}$$

.

The errors of neighboring measurements of Doppler integrals are correlated with a coefficient of 0.5:

$$E\left[{\epsilon }_i{\epsilon }_j\right]=\left\{\begin{array}{l}{\delta }_{\epsilon }^2............i=j\\ -0.5{\delta }_{\epsilon }^2......\left|I-j\right|=\mathrm{one}\\ 0............\left|I-j\right|>\mathrm{one}\end{array}\right\}\left(\mathrm{fifteen}\right)$$

Then

. $${\delta }_{\Sigma }^2=\left(n-\mathrm{one}\right){\delta }_{\epsilon }^2-2\cdot 0.5n{\delta }_{\epsilon }^2={\delta }_{\epsilon }^2\left(16\right)$$

.

Thus, the standard error of the range increment by the Doppler method does not depend on the duration of the integration interval and on dividing this interval into parts. 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.

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 of the measurement of hydrometeorological parameters.

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. Patent JP 60107490, 06/12/1985.

5. Patent RU 2328757, July 10, 2008.

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

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

8. US patent No. 42220044 A1, 09/02/1980.

9. Patent RU No. 2432589, 10.27.2011.

Claims (1)

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 all-metal, cigar-shaped, in the lower part of which there is a retractable anchor device that stabilizes the device is mounted on the upper part of the body and is made in the form of wings articulated with the body in the upper part by means of hinges, and in the lower part of the body by means of rubber dampers ators, the parachute system elements are also located in the upper part of the hull, the power supply is equipped with a generator articulated with a stabilizing device, characterized in that the hull 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 hull with flat springs, with the odd lobes fixed with a slope up and the even lobes fixed with a slope down, the optional GPS unit contains a four-channel receiver of satellite signals with the possibility of simultaneous measurement of deltap-range to four artificial Earth satellites, while the satellite communication channel receiver contains a navigation filter to simulate the movement of the buoy.

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