JP4958424B2 - Electric field detection method, apparatus, electric field detection method program, moving object position estimation detection method, apparatus, and moving object position estimation detection method program - Google Patents

Description

  The present invention relates to a method and apparatus for accurately detecting only a desired electric field strength in a certain field. In particular, it relates to electric field detection in the sea. Further, the present invention relates to a moving body position detection method for detecting the position of the moving body based on the detected electric field.

Various detections of objects, events, and the like have been conventionally performed by detecting temporal changes in an electric field. For example, there is also a method for detecting the position (amount of deviation) of a moving target based on orthogonal three-axis components of a signal generated by an electric field generated by a ship (see, for example, Patent Document 1).
JP 2000-304533 A

  In the above method, it is assumed that there is no electric field noise (noise) naturally occurring on the sea surface. Based on this assumption, when the moving body moves in seawater, the time series data of the electric field signal to be detected can be expressed by a theoretical formula, and the position etc. is estimated using the least square method, Detection is in progress.

  However, when seawater, which is a conductive medium, moves across the geomagnetism (tide flows), an induced electromotive force is generated by electromagnetic induction. Then, when the electric field sensor is in seawater under geomagnetism, stray noise caused by the induced electromotive force generated in the vicinity of the electric field sensor is superimposed on the electric field signal (time series data) detected by the electric field sensor. As a result, the detection accuracy of an electric field generated by a desired object, event, or the like is lowered. As the tidal flow velocity increases, the noise increases. For example, even in an environment where the tidal flow velocity is several m / s, the accuracy of the position detection is reduced. In addition, depending on the level of stray noise, an electric field generated by a desired object, event, etc. may be buried in the noise, and it may be impossible to estimate and detect the position or the like. As described above, there is a factor that generates an electric field in addition to a desired electric field, and it is necessary to always take measures against noise in order to increase the detection accuracy of the electric field. This is also necessary in order to increase the estimated detection accuracy of the position and the like.

  Therefore, the present invention solves the above-described problems, copes with the effects of naturally occurring (floating) noise, especially in the sea, and can detect an electric field generated based on a desired object, event, etc. with high accuracy. The purpose is to provide a method and the like. It is another object of the present invention to provide a method and the like that can estimate and detect the position of a moving body with high accuracy based on the detected electric field.

  The electric field detection method according to the present invention measures at least the electric field and the velocity of seawater by means provided in the sea, and the seawater is geomagnetic based on the velocity of the seawater and the measured or determined geomagnetic flux density data. And a step of calculating a value based on the induced electromotive force generated by crossing the line and a step of removing a component of the value based on the induced electromotive force from the electric field.

  In addition, the position detection and estimation method according to the present invention measures at least the electric field and the velocity of seawater in time series by means provided in the sea, and the magnetic flux due to the velocity of the seawater and the measured or determined geomagnetism. Based on the density data, the value of the induced electromotive force generated by the seawater crossing the geomagnetism is calculated, the component of the induced electromotive force is removed from the electric field, and the electric field data generated by the mobile body navigating the sea surface or the sea is obtained. The calculation step and the estimation detection means apply a least square method using a residual to determine the parameter values such that the value of the electric field data generated by the moving body satisfies the theoretical formula for the point current source And estimating and detecting at least the current and / or future position of the moving body based on the determined parameter value.

  In addition, the position detection and estimation method according to the present invention measures at least the electric field and the velocity of seawater in time series by means provided in the sea, and the magnetic flux due to the velocity of the seawater and the measured or determined geomagnetism. Based on the density data, the value of the induced electromotive force generated by the seawater crossing the geomagnetism is calculated, the component of the induced electromotive force is removed from the electric field, and the electric field data generated by the mobile body navigating the sea surface or the sea is obtained. The value of the parameter that satisfies the step of calculating and the expression expressed by the sum of the electric field component generated by the moving body and the electric field component based on the mirror image electrode virtually set with the sea surface and the sea bottom as a boundary. And estimating and detecting at least the current and / or future position of the moving body based on the determined parameter value.

  In addition, in the position and the like estimation detection method according to the present invention, values are further determined for parameters including the electrical conductivity of seawater and the seabed.

  Also, the Gauss-Newton method is applied to the least square method used in the position estimation estimation method according to the present invention.

  In addition, the estimated position detection method according to the present invention further detects and detects the closest position with respect to the speed of the moving body and the reception position of the electric field signal.

  In addition, the position and the like estimation detection method according to the present invention determines the moving object or its type based on the electric field strength or the parameter value.

  The electric field detection device according to the present invention includes an electric field detection means for detecting an electric field with each component in three axial directions, a tidal current measurement means for measuring the velocity of seawater with each component in three axial directions, and the speed and measurement of seawater. Based on the data of each component of the magnetic flux density by the determined or defined geomagnetism, the induced electromotive force estimation means for performing the calculation based on the induced electromotive force generated to generate the electric field floating noise data, and the electric field floating noise data, And an electric field correction means for correcting data based on the electric field.

  The electric field detection device according to the present invention further includes magnetic field detection means for detecting a magnetic field with each component in three axial directions, and the induced electromotive force estimation means is calculated by data of each component of magnetic flux density due to geomagnetism based on the magnetic field. Is to do.

  In addition, the position and other estimation detection apparatus according to the present invention includes an electric field detection unit that detects an electric field with each component in three axial directions, a tidal current measurement unit that measures the velocity of seawater with each component in three axial directions, and the velocity of seawater. In addition, the induced electromotive force estimation means for calculating the induced electromotive force generated as electric field floating noise data based on the measured or determined magnetic flux density component data, and the electric field data detected by the electric field detection means And a data recording means for recording the electric field floating noise data in time series, an electric field correcting means for correcting the data based on the electric field based on the electric field floating noise data, and the value of the electric field data corrected by the electric field correcting means in the point current source. The parameter value is determined by performing the iterative calculation using the least squares method using the residual until a predetermined convergence condition is satisfied so as to satisfy the theoretical formula of the electric field. Was based on the value of the parameter is obtained by a detecting means for estimating detecting the current and / or future location of the at least mobile.

  In addition, the position and other estimation detection apparatus according to the present invention includes an electric field detection unit that detects an electric field with each component in three axial directions, a tidal current measurement unit that measures the velocity of seawater with each component in three axial directions, and the velocity of seawater. In addition, the induced electromotive force estimation means for calculating the induced electromotive force generated as electric field floating noise data based on the measured or determined magnetic flux density component data, and the electric field data detected by the electric field detection means The data recording means for recording the electric field floating noise data in time series, the electric field correcting means for correcting the data based on the electric field by the electric field floating noise data, and the value of the electric field data corrected by the electric field correcting means are the moving body. Satisfies the expression expressed as the sum of the electric field component directly emitted from the sea surface or a ship navigating in the sea and the electric field component based on the mirror image electrode virtually set with the sea surface and sea bottom as the boundary And detecting means for estimating and detecting at least the current and / or future position of the moving object based on the determined parameter value and determining a value of such a parameter by applying a least square method using a residual. It is provided.

  The electric field detection device according to the present invention further includes magnetic field detection means for detecting a magnetic field with each component in three axial directions, and the induced electromotive force estimation means is calculated by data of each component of magnetic flux density due to geomagnetism based on the magnetic field. Is to do.

  Moreover, the detection means of the position estimation estimation device according to the present invention further estimates and detects the speed of the moving object and the closest approach position to the detection means based on the parameter values.

  In addition, the detection means of the position estimation detection apparatus according to the present invention determines the moving object or its type based on the physical quantity or the parameter value.

Further, the program of the electric field detection method according to the present invention is based on the measured or determined geomagnetic flux density and at least seawater velocity data obtained from means provided in the sea, and the seawater crosses the geomagnetism. And calculating a value based on the induced electromotive force generated as a data and calculating the electric field data corrected by removing a component of the value based on the induced electromotive force from the electric field data in the sea. It is what you want to do.

In addition, the position estimation detection program according to the present invention is based on the measured or determined geomagnetic flux density and at least seawater velocity data obtained from means provided in the sea. Calculating the value of the induced electromotive force generated by crossing the sea, removing the component of the induced electromotive force from the electric field data in the sea, and calculating the electric field generated by the moving object navigating the sea surface or the sea as data in time series And the least square method using the residual is applied to determine the parameter value such that the value of the electric field data generated by the moving body satisfies the theoretical formula for the point current source, and the determined parameter value Based on this, at least the present and / or future position of the moving object is estimated and detected by the computer.

In addition, the position estimation detection program according to the present invention is based on the measured or determined geomagnetic flux density and at least seawater velocity data obtained from means provided in the sea. Calculating the value of the induced electromotive force generated by crossing the sea, removing the component of the induced electromotive force from the electric field data in the sea, and calculating the electric field generated by the moving object navigating the sea surface or the sea as data in time series And a step of determining a parameter value that satisfies a formula expressed by a sum of an electric field component generated by a moving body and an electric field component based on a mirror image electrode virtually set with a seawater surface and a sea bottom as a boundary. Based on the value of the parameter, the computer performs at least a step of estimating and detecting the current and / or future position of the moving body.

    Moreover, the program of the position estimation estimation method according to the present invention further causes the computer to determine values for parameters including the electrical conductivity of the seawater and the seabed.

  Further, the program of the estimation detection method for position and the like according to the present invention further causes the computer to perform estimation detection of the closest position with respect to the speed of the moving body and the reception position of the electric field signal based on the parameter values.

  In addition, the program of the position and the like detection method according to the present invention causes the computer to further determine the moving object or its type based on the strength of the electric field or the value of the parameter.

  According to the present invention, in electric field detection in the sea, more accurate electric field detection is performed by calculating and removing a value based on the induced electromotive force generated when seawater that is noise in the electric field crosses the geomagnetism. be able to. Thereby, for example, the accuracy of the position estimation of the moving body by the electric field detection, the earthquake prediction, etc. can be improved.

  In addition, according to the present invention, the estimation detection means is configured to detect the point current source from the electric field data in which the electric field generated by the mobile body is time-series after removing the component based on the induced electromotive force generated by the seawater crossing the geomagnetism. The value of the parameter that satisfies the theoretical formula is determined, and at least the current and / or future position of the moving object is estimated and detected based on the determined parameter value, so the position and the like are estimated accurately. Detection can be performed.

  Further, according to the present invention, after removing the component based on the induced electromotive force generated by the seawater crossing the geomagnetism, the estimation detection means is detected from the moving body from the electric field data in which the electric field generated by the moving body is time-series. Determine the value of the parameter that satisfies the expression expressed as the sum of the electric field component directly emitted and the electric field component based on the mirror image electrode virtually set with the seawater surface and sea bottom as the boundary, and based on the determined parameter value Thus, at least the current and / or future position of the moving object is estimated and detected, so that a result closer to reality can be obtained, and the position and the like can be estimated and detected accurately.

  In addition, according to the present invention, when setting the mirror image electrode with the seawater surface and the seafloor as a boundary, a parameter relating to the electrical conductivity of the seabed is added, and the value is determined. Based on the determined value The direction of the moving body can be corrected with certainty.

  In addition, according to the present invention, the Gauss-Newton method is applied to the least square method, so that the least square method with good convergence stability is applied and the estimation of position and the like is quickly performed while reducing the calculation time. It can be performed with high accuracy.

  Furthermore, according to the present invention, it is possible to further estimate and detect the closest position (minimum distance) between the speed of the moving object and the reception position of a signal having a physical quantity of 2 or more based on the determined parameter value.

  Further, according to the present invention, the size of the physical quantity or the parameter value and the moving object corresponding to the physical quantity or the characteristics of the type are stored in a database, for example, so that the moving object is obtained based on the obtained signal and parameter value. Alternatively, the type can also be determined.

  According to the present invention, in the electric field detection in the sea, the induced electromotive force estimation means calculates the value based on the induced electromotive force generated by the seawater that becomes noise in the electric field crossing the geomagnetism, and generates the electric field floating noise data. Then, the electric field correction unit corrects the data based on the electric field based on the electric field floating noise data and removes the influence of the noise, so that the electric field can be detected with higher accuracy. Thereby, for example, the accuracy of the position estimation of the moving body by the electric field detection, the earthquake prediction, etc. can be improved.

  Further, according to the present invention, the induced electromotive force estimation means generates the electric field floating noise data based on the data of each component of the magnetic flux density by the geomagnetism obtained from the magnetic field detected by the magnetic field detection means. High-precision calculations can be expected by calculations based on actual measurements.

  Further, according to the present invention, the induced electromotive force estimation means calculates a value based on the induced electromotive force generated when seawater crosses the geomagnetism to generate electric field floating noise data, and the electric field correction means performs the electric field floating noise data. From the data based on the electric field corrected by the above, the estimated detection means determines a parameter value that satisfies the theoretical formula relating to the point current source, and at least the present and / or future of the moving object based on the determined parameter value Since the position is estimated and detected, the position and the like can be estimated and detected accurately. This is particularly effective for estimating and detecting the position and the like when the distance between the detection means and the moving body is short.

  Further, according to the present invention, the induced electromotive force estimation means calculates a value based on the induced electromotive force generated when seawater crosses the geomagnetism to generate electric field floating noise data, and the electric field correction means performs the electric field floating noise data. From the data based on the electric field corrected by, the estimated detection means satisfies the expression expressed by the sum of the electric field component directly emitted from the moving body and the electric field component based on the mirror image electrode virtually set with the seawater surface and sea bottom as the boundary. The value of such a parameter is determined, and at least the current and / or future position of the moving object is estimated and detected based on the determined parameter value, so that a more realistic result can be obtained and accurately Position and the like can be estimated and detected.

  Further, according to the present invention, the induced electromotive force estimation means generates the electric field floating noise data based on the data of each component of the magnetic flux density by the geomagnetism obtained from the magnetic field detected by the magnetic field detection means. High-precision calculations can be expected by calculations based on actual measurements.

  Further, according to the present invention, the detection means further estimates and detects the closest position (minimum distance) between the speed of the moving object and the reception position of the electric field signal based on the determined parameter value, so that the position other than the position is detected. Further information can be obtained.

  Further, according to the present invention, if the detection means stores, for example, a physical quantity size or parameter value and a moving object corresponding to the physical quantity or characteristics of the type in a database, based on the obtained signal and parameter value. More detailed information such as the moving object or its type can be obtained.

  According to the present invention, in the electric field detection in the sea, the computer calculates the value based on the induced electromotive force generated by the seawater that becomes noise in the electric field crossing the geomagnetism, and causes the computer to execute the program to be removed. Electric field detection with higher accuracy can be performed. Thereby, for example, the accuracy of the position estimation of the moving body by the electric field detection, the earthquake prediction, etc. can be improved.

  In addition, according to the present invention, after removing the component based on the induced electromotive force generated when seawater crosses the geomagnetism, the theoretical formula related to the point current source is obtained from the electric field data in which the electric field generated by the moving body is time-series. Since the value of the parameter that satisfies the condition is determined, and the computer is caused to execute a program that estimates and detects at least the current and / or future position of the moving object based on the determined parameter value, the position is accurately determined. Etc. can be estimated and detected. This is particularly effective for estimating and detecting the position and the like when the distance between the detection means and the moving body is short.

  In addition, according to the present invention, after removing a component based on an induced electromotive force generated when seawater crosses the geomagnetism, an electric field component directly emitted from the moving object from electric field data obtained by chronologically generating an electric field generated by the moving object. And the value of the parameter satisfying the equation expressed by the sum of the electric field component based on the mirror image electrode virtually set with the seawater surface and the seafloor as the boundary, and at least the moving body based on the determined parameter value Since the computer is caused to execute a program that estimates and detects the current and / or future position, it is possible to obtain a result closer to reality and accurately estimate and detect the position and the like.

  Further, according to the present invention, when setting the mirror image electrode with the seawater surface and the seafloor as a boundary, a parameter relating to the electrical conductivity of the seabed is added, and the value is determined by the computer. Based on this, the direction of the moving body can be corrected with certainty.

  In addition, according to the present invention, the computer is further made to detect and detect the closest approach position with respect to the receiving position of the velocity and physical quantity of the moving object based on the parameter values, so that information other than the position can be obtained. it can.

  In addition, according to the present invention, the program of the estimation detection method of the moving object position and the like has caused the computer to further determine the moving object or its type based on the magnitude of the physical quantity or the parameter value. More detailed information can be obtained.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing the configuration of a moving body position detecting device partially including an electric field detecting device according to a first embodiment of the present invention. Here, in this Embodiment, the navigation body which moves the sea surface or the sea is assumed and demonstrated. Therefore, the moving body position detection device is provided in the sea (including the seabed). The medium that conducts electricity is seawater (therefore, the electric field detector 1 detects the electric field strength in the sea as a signal). In addition, it is assumed that the moving body is performing a uniform linear motion. The location where the moving body position detection device (especially the electric field detector 1) is provided is not particularly limited. However, if the seawater salinity is stable, the detection accuracy of the electric field and the like is further increased. In addition, the accuracy of estimation and detection of the position of the moving body can be improved.

  In FIG. 1, an electric field detector (electric field sensor) 1 detects (receives) electric field intensity as a signal and converts it into an electric signal (hereinafter referred to as an electric field signal) (in some cases, based on other detected electric physical quantities). An electric signal whose electric field strength is calculated based on the signal may be used as an electric field signal, or may be converted into an electric signal after being converted into an optical signal). Here, the electric field detector 1 is a detector having three detection means orthogonal to each other or a detector representing a three-axis sensor, and can detect in the three-axis direction of an orthogonal (relative) coordinate system. .

  The magnetic detector (magnetic sensor) 2 also detects (receives) a magnetic field (magnetic flux density) as a signal and converts it into an electric signal (hereinafter referred to as a magnetic field signal) (in some cases, other detected magnetic physical quantities). The electric signal obtained by calculating the magnetic flux density based on the signal based on the above may be used as the magnetic field signal). Similarly to the electric field detector 1, the magnetic detector 2 can detect in the three-axis directions of the orthogonal coordinate system. In the present embodiment, it is mainly used for calculation for calculating the induced electromotive force generated in the electric field detector 1.

  The tide meter 3 measures the moving speed of seawater (the speed of the sea tide) and converts it into an electrical signal (hereinafter referred to as a tide signal). Also for the tide meter 3, it is assumed that each component of the velocity in the three-axis directions can be transmitted as a tide signal. The A / D converters 4a, 4b, and 4c, for example, perform processing such as sampling and convert electric field signals, magnetic field signals, and power flow signals into digital data signals (hereinafter, data based on each signal is converted into electric field signal data). , Magnetic field signal data and tidal current data). Here, since the distance between the electric field detector 1 and the magnetic detector 2 is negligibly small compared to the distance between the apparatus and the moving body, the origins of the respective coordinate systems are the same (in the same position). Shall. Further, the electric field detector 1, the magnetic detector 2, and the tide meter 3 are assumed to have the same three-axis direction (coordinate system).

  The inclinometer 5 measures the degree of inclination of the moving body position detection device (in particular, the electric field detector 1, the magnetic detector 2, and the tide meter 3) when the direction perpendicular to the sea surface is the Z axis. Then, a signal including data based on the measurement (hereinafter, this data is referred to as inclination data) is transmitted to the induced electromotive force estimator 6 and the electric field signal processor 7. Then, the induced electromotive force estimator 6 corrects the tidal current data and the magnetic field signal data based on the inclination data, and estimates and calculates the value of the induced electromotive force generated by the seawater flow based on the corrected data. Is recorded in the data collector 8. The electric field signal processor 7 corrects the electric field signal data based on the inclination data, and stores the electric field signal data in the data collector 8 (here, in the following description, the electric field signal data, the magnetic field signal data, The tidal current data is assumed to be unaffected by the slope).

  The data collector 8 includes a data processing unit 8A and a data recording unit 8B. The data processing unit 8A is a so-called database management system (DBMS). A process of associating the electric field signal data and the electric field floating noise estimation data with the time data is performed. The data recording unit 8B is composed of a recording device (means), and records electric field signal data, electric field floating noise estimation data, and time data for at least a certain time or a certain number. This data collector 8 serves as a so-called database.

  The position etc. estimation detector 9 includes an electric field signal data correction unit 9a and a position etc. estimation detection unit 9b. The electric field signal data correction unit 9a performs calculation based on the electric field signal data and the electric field floating noise estimation data, and generates electric field signal correction data. The position etc. estimation detection unit 9b estimates and calculates the position of the moving body based on the electric field signal correction data.

  Here, the induced electromotive force estimator 6, the electric field signal processor 7, and the position etc. estimation detector 9 are composed of control arithmetic processing means such as a computer centering on a CPU (Central Processing Unit), for example. Then, the control calculation processing means executes a program that preliminarily calculates the estimation calculation processing procedure for the position, etc., and performs processing based on the program to perform calculation such as addition / subtraction / multiplication / division based on each formula described later, and further calculation Estimating the position or the like is realized by judging convergence or the like based on the result. Here, each device is configured as a separate device (means). However, for example, processing based on a program performed by each device may be performed by one control arithmetic processing device.

  Although not an indispensable means in the apparatus according to the present embodiment, an approach detector and a movement detector are provided to determine the approach and movement of the moving object. For example, the data collector 8 starts or ends the recording of the electric field signal. Etc. can also be controlled. Further, by providing a depth meter in the vicinity of the electric field detector 1, in the case of a ship in which the moving body travels on the water surface, for example, the depth (height) that is the distance in the Z-axis direction is measured, and the known value is obtained. Can be used. Therefore, the number of parameters (unknown variables) described later can be reduced.

  In this embodiment, for example, the position of the moving body is estimated based on the strength of the electric field generated by the current generated by the moving body, but there are factors that generate an electric field due to a natural phenomenon in the sea. For example, seawater as a conductor moves as, for example, a tidal current, and an induced electromotive force is generated by crossing geomagnetism (magnetic field by the earth). Since this induced electromotive force becomes noise with respect to the electric field generated by the moving body and is added to the electric field signal by the electric field detector 1 in the sea (or the bottom of the sea), the estimation of the position and the like by the electric field signal data based on this electric field signal has low accuracy. .

  Therefore, in the present embodiment, the velocity of the seawater (conductor) at the position where the device is provided (the tidal current data obtained by the tide meter 3) and the magnetic flux density due to geomagnetism at the position where the device is provided (by the magnetic detector 2). The induced electromotive force estimator 6 performs an estimation calculation based on the obtained magnetic field signal data), and calculates the induced electromotive force (this is referred to as induced electromotive force e) in time series. Assuming that the component of the induced electromotive force e is an electric field floating noise included in the electric field signal based on the electric field detector 1, electric field floating noise data based on the induced electromotive force e (this value is set as E ′) is generated, and the data Let the collector 8 record.

  The induced electromotive force e estimated by the induced electromotive force estimator 6 is expressed by the following equation (1) based on the magnetic flux density B and the tidal velocity (seawater velocity) v due to geomagnetism. Here, the magnetic flux density B and the tidal flow velocity v are vectors, and the induced electromotive force e is an outer product of the magnetic flux density B and the tidal flow velocity v. The induced electromotive force e is also a vector. Here, the directions of the magnetic flux density B, the tidal flow velocity v, and the induced electromotive force e are orthogonal to each other (Fleming's right-hand rule).

On the other hand, electric field signal data (this value is set to E1) is also recorded in the data collector 8 by the electric field signal processor 7. Then, the electric field signal data correction unit 9a calculates the corrected electric field (electric field generated by the moving body) at each time based on E1 and E ′ based on the following equation (2), and the electric field signal correction data (this value) Is E). Here, E, E1, and E ′ are three-dimensional vectors.
E = E1-E ′ (2)

  FIG. 2 is a diagram illustrating the relationship between the position of the moving body and the electric field signal generated by the moving body. Since seawater is an electrolyte solution, if different metals exist in seawater, a potential difference is generated. In this case, a current flows from a metal having a high ionization tendency to a metal having a low ionization tendency, and the anode surface is corroded. In a ship, for example, a hull outer plate serves as an anode (steel) and a propeller serves as a cathode (copper alloy or the like), and a current is returned to the hull outer plate via a propeller main shaft to form a closed circuit. This current is the corrosion current. Moreover, in order to prevent metal corrosion due to such a corrosion current, an anticorrosion current may be passed. Therefore, for example, an anode electrode such as protective zinc or platinum for supplying current to seawater is provided on the hull. Moreover, the propeller, rudder, etc. which are provided in the stern part function as a cathode electrode for an electric current to flow in through seawater (inhale an electric current). And these become a current source (henceforth a point current source) with respect to the electric current which flows through seawater.

  If the distance between the electric field detector 1 and the moving body is long or the distance between the anode electrode and the cathode electrode is short, the point current source can be regarded as a dipole and a theoretical formula based on a dipole moment can be used. If this is not the case, the actual condition will deviate from the formula, and the parameter value determined based on the actual measurement value will deviate significantly from the true value, making it impossible to accurately detect the position of the moving object (actually the distance In some cases, the closer to is, the more accurate estimation and detection of the position is required). In the present embodiment, by performing calculation according to a point current source that is a monopole, accurate detection of the position of the moving body and the like is performed based on an equation in accordance with reality. The least squares method (especially the nonlinear least squares method is used for detecting the position and the like. Hereinafter, the least squares method is simply used. Specifically, the residual of the value obtained from the theory and the value obtained from the measured signal is used. The position is calculated based on the value of the parameter when it is determined that the predetermined convergence condition is satisfied, so that the sum of squares is minimized.

FIG. 3 is a diagram illustrating the relationship between the moving body and the point current source. When the moving body moves in the immediate vicinity of the electric field detector 1 by a uniform linear motion, the three-axis components (E _X , E _Y , E _Z ) of the electric field signal by the point current source provided on the moving body are expressed by the following equations: It is represented by (3) to (5).

E _X = ΣI _{σ i} · X _i / (X _i ² + Y _i ² + Z _i ² ) ^3/2 (3)
E _y = ΣI _{σ i} · Y _i / (X _i ² + Y _i ² + Z _i ² ) ^3/2 (4)
E _z = ΣI _{σ i} · Z _i / (X _i ² + Y _i ² + Z _i ² ) ^3/2 (5)

Here, the positions X ₁ and Y ₁ of the _first point current source from the reference position are
X ₁ = X ₀ + V cos α · t (6)
Y ₁ = Y ₀ + Vsin α · t (7)
age,
X _i = X ₁ + d _i · cos α · t (8)
Y _i = Y ₁ + d _i · sin α · t (9)
And

However,
X ₀ , Y ₀ : Reference position i: Number of point current sources (1, 2,...)
I σi: I _i / 4πσ ₁
I _i : Current amount of each point current source σ ₁ : Electrical conductivity of seawater (conductivity)
t: time V: moving body speed d _i : distance in the hull length direction between the first point current source and each point current source (1, 2,..., i−1)
Z _i : The height of the moving body from the electric field detector 1 (almost the same as the water depth for a ship traveling on water)
α: An angle formed by the X-axis direction of the electric field detector 1 and the moving direction of the moving body. Here, when the point current source I is viewed as a point charge Q, the point current source I and the point charge Q have a relationship of I = σ · Q / ε. ε is the dielectric constant. Also, ΣI _i = 0, that is, the sum of the point current sources is zero.

In the theoretical formula of the electric field obtained as described above, the parameter (unknown) determined for matching with the value based on the actually measured electric field signal is set as the following formula (10). Here, as described above, when the distance to the sea surface is known by the depth gauge, and the distance in the Z-axis direction to the moving body is known, Z _i may not be included in the parameter.
_{a e = (I σi, d} i, X 0, Y 0, Z i, V, α) ... (10)

The position estimation detection unit 9b adjusts each parameter by the least square method so that the value based on the electric field obtained by actual detection (the value E of the electric field signal correction data) satisfies the theoretical formula, and sets the parameter value. The position of the moving body is estimated and detected based on the determined value. When applying the method of least squares, an initial value is given to a parameter and calculation is performed. For example, with respect to the reference positions X ₀ and Y ₀ , X ₀ = 0 and Y ₀ = 0 (directly above the electric field detector 1) are set as initial values. Here, although X ₀ = 0 and Y ₀ = 0 are estimated values, they are values close to actual X ₀ and Y ₀ , so that a favorable calculation result can be obtained. Although there are various methods for the least square method, the Gauss-Newton method is applied in this embodiment. Here, it is assumed that the calculation is performed using the Levenberg-Marquardt method based on the Gauss-Newton method, taking into account the balance between calculation time and convergence stability, the relationship with the function, etc. However, other solutions based on the Gauss-Newton method, such as the damping method and the Powell method, may be used. Further, instead of the Gauss-Newton method, other nonlinear least squares methods such as the steepest descent method may be used. When applied to an electric field signal (electric field signal data), the following equations (11) to (13) are established.

^{_{P e t P e · Δa e}} = -P e t r e ... (11)
^{_{P e t P e = P ex}} t P ex + P ey t P ey + P ez t P ez ... (12)
^{_{P e t r e = P ex}} t r ex + P ey t r ey + P ez t r ez ... (13)

However,
P _ex : Matrix consisting of the first derivative of each parameter of the electric field signal in the x-axis direction P _ey : Matrix consisting of the first derivative of each parameter of the electric field signal in the y-axis direction P _ez : Each parameter of the electric field signal in the z-axis direction A matrix consisting of first-order derivatives: r _e : sum of squares of residual Δa _e : a parameter correction value.

Then, the position etc. estimation detection unit 9b then continues until the sum of squares of the residual in the equation (13) satisfies a predetermined convergence condition (for example, the sum of squares of the residual is equal to or less than a predetermined value or the rate of change of the sum of squares is reduced) Iterative calculation is performed (until the value becomes a predetermined value or less). In this iterative calculation, until it is determined that the moving body is closest, the value calculated based on the electric field signal correction data obtained from the actual signal is used as X ₀ , used as an initial value of Y _0. Then, CPA (Closest Point of Approach: closest approach position (position at t = 0)) is estimated and detected based on the parameters (X ₀ , Y ₀ ) that satisfy the convergence condition. Further, by substituting the determined values of the parameters V, α, d _{i into} the expressions (6), (7), (8), and (9), the current position of the moving body and the position of each point current source (stern Etc.) can be estimated and detected. Further, since the moving body is treated as having a constant velocity linear motion, a future position can also be predicted (estimated or detected) based on the estimated and detected current position and speed.

  Further, for example, by associating data such as electrical physical quantities and parameter values generated from a moving body with data on the moving body or its type, the electric field signal correction data and the determined parameter value can be used to determine the moving body or its The type can also be specified.

  As described above, according to the first embodiment, the induced electromotive force e generated when the seawater as the conductor crosses the geomagnetism is converted into the magnetic field signal from the magnetic detector 2 and the tidal current signal from the tide meter 3. On the basis of this, the induced electromotive force estimator 6 performs an estimation calculation, and the electric field signal data correction unit 9a determines that the component of the induced electromotive force e is electric field floating noise included in the electric field signal from the electric field detector 1. Since the electric field signal correction data E in which the electric field floating noise component is removed from the signal is generated, the position of the position is estimated based on the corrected data value after removing the noise component generated by the natural phenomenon from the electric field signal. It is possible to perform calculations such as the above, and it is possible to estimate the position and the like with higher accuracy.

  Then, based on the electric field signal correction data, the least square method is performed by using the theoretical formula of the electric field generated by the current flowing from the point current source of the ship so that the position and the like detection unit 9b obtains a more realistic result. The value of the parameter is determined so that the value based on the electric field signal is applied and the current and / or future position of the moving object is estimated and detected based on the determined value. Estimation and detection can be performed. This is particularly effective for estimating and detecting the position and the like when the distance between the electric field detector 1 and the moving object is short.

  In addition to estimating and detecting the current and / or future position of the mobile object, detailed data on the mobile object can be obtained by estimating and detecting the closest approach position and speed based on the determined parameter values. Can be estimated and obtained. For example, if data such as electric field strength and parameter values by a moving object is associated with the moving object or its type data, the moving object or its type can be determined from the obtained electric field signal data and the determined parameter value. Can also be specified. Furthermore, since the propeller or the like serves as a point current source, the position of the stern can be specified. Then, for example, if the bow position can be specified based on a signal such as a magnetic field, the hull length can be estimated, and the moving object or its type can also be specified.

  Furthermore, since the Gauss-Newton method, particularly the Levenberg-Marquardt method or the modified Marquardt method, is used as the solution of the least square method, the least square method with good convergence stability is applied while reducing the calculation time. The position and the like can be detected quickly and with high accuracy.

Embodiment 2. FIG.
In the above-described embodiment, the estimation calculation of the induced electromotive force e is performed based on the equation (1), and the subsequent calculation is performed assuming that this value is the same value as the electric field floating noise included in the electric field signal. Here, for example, depending on the shape or the like of the electric field detector 1, the value of the induced electromotive force e simply calculated by applying the equation (1) is assumed to be the same as the electric field floating noise component included in the electric field signal. There are cases where it cannot be handled. Therefore, for example, correction coefficients l (l _x , l _y , l _z ) corresponding to the shape of the electric field detector 1 are determined, and correction is performed by multiplying the induced electromotive force e as shown in the following equation (14). To do. And the electric field floating noise data which estimated the component of the induced electromotive force e after correction | amendment in time series are produced | generated. Thereby, the value of the electric field floating noise E ′ according to the environment such as the shape of the electric field detector 1 can be calculated. here,
E ′ _x = l _x · e _x
E ′ _y = l _y · e _y (14)
E ' _z = l _z · e _z

Embodiment 3 FIG.
In the embodiment described above, the value of the magnetic field signal data based on the magnetic field signal from the magnetic detector 2 is set as the value of the geomagnetism at the position where the device is provided, and the induced electromotive force e is calculated based on the magnetic field signal data and the tidal current data. did. The present invention is not limited to this.

  Strictly speaking, the geomagnetism at the position where the device is provided is not constant and often changes, but depending on the relative speed change with seawater due to only the geomagnetism fluctuation, electric field floating noise can occur. It is considered that the induced electromotive force e is not generated. For example, if the fluctuation due to a magnetic storm or the like is so small as to be negligible, for example, the induced electromotive force estimator 6 stores data relating to geomagnetism at a position where the device is provided in advance as magnetic field signal data, and the tide meter 3 The induced electromotive force e may be estimated and calculated in the same manner as in the first embodiment based on the tidal current data.

Embodiment 4 FIG.
FIG. 4 is a diagram showing a mirror image point current source (mirror image electrode) for a point current source (electrode) in the hull. It is conceivable that the electric field generated in seawater (which becomes an electric field signal) is most affected by the atmosphere and the boundary of the seabed (seawater surface and seafloor) having a different dielectric constant (electrical conductivity) from seawater. Therefore, using the mirror image theory, the mirror image point current source for the point current source in the hull is virtually assumed, and the sum of the electric fields generated by all the point current sources is defined as the electric field (electric field signal) generated in the seawater (hull wall, seawater temperature However, it is difficult to consider all the influences, and since it is negligible, it is omitted here).

  Here, mirror image theory means that, for example, when two different dielectric media (seawater and air, seawater and seabed) are in contact with each other at the interface (seawater surface, seafloor), the charge (dots) in one medium A method for obtaining an electric field by virtually providing an electric charge (point current source, electrode) in another medium having no electric charge, instead of directly solving an electric field generated by a current source or an electrode in consideration of boundary conditions. It is. In this case, the electric field can be obtained without disturbing the boundary condition.

  In the present embodiment, a mirror image point current source is virtually provided (placed) to calculate the theoretical value of the electric field, thereby reducing the deviation from the actual measurement value, and performing more accurate position detection and the like. Although the processing of the position and the like estimation detection unit 9b is different, the configuration is the same as that of the moving body position and the like detection device of the first embodiment, and therefore this embodiment will also be described with reference to FIG.

In this embodiment, (a) For each point current source A in the hull,
(B) A mirror image point current source (hereinafter referred to as a mirror image point current source B) paired with the point current source of (a) across the seawater surface.
(C) A mirror image point current source (hereinafter referred to as mirror image point current source C) that is paired with the point current source of (a) across the sea floor.
(D) A mirror image point current source (hereinafter referred to as a mirror image point current source D) paired with the mirror image point current source of (b) across the sea floor.
These three mirror image point current sources are virtually placed and the electric field relating to each point current source is calculated. Although a mirror image point current source based on other conditions is also conceivable, it is omitted here because it is negligibly small (the mirror image point current source D may be ignored in some cases).

Assuming that the current value at the point current source (electrode) provided on the hull is I _A (I _i in the first embodiment), the current value I _B of the virtual point current source is expressed by the following equation (15). . Similarly, the current value I _C current value I _D is expressed by the following equations (16) and (17). Here, in this embodiment, each component of the electric field represented by (3) to (5) described in the first embodiment is expressed as (E _Ax , E _Ay , E _Az ).
I _B = (σ ₁ −σ ₂ ) I _A / (σ ₁ + σ ₂ ) (15)
I _C = (σ ₁ −σ ₃ ) I _A / (σ ₁ + σ ₃ ) (16)
I _D = (σ ₁ −σ ₂ ) I _A / (σ ₁ + σ ₂ ) (17)

When considered based on the equations (15) to (17), the electric field generated by the mirror image point current source B is represented by the following equations (18) to (20).
E _Bx = {(σ ₁ −σ ₂ ) I _σi / (σ ₁ + σ ₂ ) } ・ X _i
/ {X _i ² + Y _i ² + (− Z _i ) ² } ^3/2 (18)
E _By = {(σ ₁ −σ ₂ ) I σ _i / (σ ₁ + σ ₂ )} · Y _i
/ {X _i ² + Y _i ² + (− Z _i ) ² } ^3/2 (19)
E _BZ = {(σ ₁ −σ ₂ ) I σ _i / (σ ₁ + σ ₂ )} · (−Z _i )
/ {X _i ² + Y _i ² + (− Z _i ) ² } ^3/2 (20)

Similarly, the electric field generated by the mirror image point current source C is expressed by the following equations (21) to (23).
E _Cx = {(σ ₁ −σ ₃ ) I σ _i / (σ ₁ + σ ₃ )} · X _i
/ {X _i ² + Y _i ² + (2Zs−Z _i ) ² } ^3/2 (21)
E _Cy = {(σ ₁ −σ ₃ ) I σ _i / (σ ₁ + σ ₃ )} · Y _i
/ {X _i ² + Y _i ² + (2Zs−Z _i ) ² } ^3/2 (22)
E _CZ = {(σ ₁ −σ ₃ ) I σ _i / (σ ₁ + σ ₃ )} · (2Zs−Z _i )
/ {X _i ² + Y _i ² + (2Zs−Z _i ) ² } ^3/2 (23)

Furthermore, the electric field generated by the mirror image point current source D is expressed by the following equations (24) to (26).
E _Dx = {(σ ₁ −σ ₂ ) I _σi / (σ ₁ + σ ₂ )} · X _i
/ {X _i ² + Y _i ² + (Z _i −2Zs) ² } ^3/2 (24)
E _Dy = {(σ ₁ −σ ₂ ) I σ _i / (σ ₁ + σ ₂ )} · Y _i
/ {X _i ² + Y _i ² + (Z _i −2Zs) ² } ^3/2 (25)
E _DZ = {(σ ₁ −σ ₂ ) I σ _i / (σ ₁ + σ ₂ )} · (Z _i −2Zs)
/ {X _i ² + Y _i ² + (Z _i −2Zs) ² } ^3/2 (26)

here,
σ ₁ : Electrical conductivity of seawater σ ₂ : Electrical conductivity of seabed σ ₃ : Electrical conductivity of air (= 0)
Zs: water depth.

The electric field (E _x , E _y , E _z ) is finally expressed by the sum of each point current source (point current source) as in the following equations (27) to (29), for example. Become. Here, depending on the environmental conditions and the like, it may be more realistic not to consider all the mirror image point current sources, and the amount of calculation increases when all terms are added. (27) to (29) In the formula, one or more terms may be omitted.
E _x = E _Ax + E _Bx + E _Cx + E _Dx (27)
E _y = E _Ay + E _By + E _Cy + E _Dy (28)
E _z = E _Az + E _Bz + E _Cz + E _Dz (29)

Based on (E _x , E _y , E _z ) calculated as described above, the parameter value is calculated and determined by the method of least squares, as in the first embodiment. Here, in the present embodiment, in addition to the parameters shown in the equation (8), for example, parameters including electrical conductivity σ ₂ of the seabed such as σ ₂ , σ ₁ −σ ₂ , σ ₁ + σ _2, etc. Is added. Here, in particular, σ ^* (conductivity ratio) where σ ^* = (σ ₁ −σ ₂ ) / (σ ₁ + σ ₂ ) is added as a parameter. Accordingly, parameters for performing position estimation and the like are set as in the following equation (30).
_{a e = (I σi, d} i, X 0, Y 0, Z i, V, α, σ *) ... (30)

Here, it is verified whether there is a combination of similar parameters in the equations (27) to (29). The electric field signal forms a signal waveform by combining values of a plurality of parameters such as position and velocity. Similarity refers to the case where there are innumerable combinations of values even with the same electric field signal waveform. At this time, parameters such as position and speed estimated from the signal are not uniquely determined and become indefinite. Similar parameters are parameters determined by k and k ′ that satisfy the expressions (27) to (29) other than the combination of k = 1 and k ′ = 1 in the following expression (31). If there are similar parameters, k and k 'can take any value, so there are an infinite number of combinations, and the values of parameters such as moving body speed and initial position are determined as one set. It will not be possible.
a _e = (k′I σ _i , kd _i , kX ₀ , kY ₀ , kZ _i , kV, α, σ ^* ) (31)

  Then, consider the identity of equations (27) to (29) based on the parameters of equation (30) and equations (27) to (29) based on the parameters of equation (31). The values of k and k ′ satisfying this identity are at most finite. Among these values, even if they exist mathematically, there are only combinations of k = 1 and k ′ = 1 that can be taken at least within the range of a realistic moving body (especially a ship). . (This is the same even if one or two terms out of the second to fourth terms in the equations (27) to (29) are omitted.) Therefore, the moving object is derived from the equations (27) to (29). The parameters such as the speed and the initial position can be determined as one set. Thereby, the speed, position, etc. of the ship navigating on the water and the moving body in the sea can be estimated.

Here, in the determined parameter value, σ ^* > 1 may be satisfied. In this case, a value obtained by performing the following correction on the determined parameter value is newly determined as the parameter value. When σ ^* > 1, the moving direction of the moving body is reversed (the direction relation of the point current source is also reversed in accordance with the direction).
I _σi after correction: −I _σi (before correction) × σ ^* (before correction)
Α after correction: α (before correction) −180 ° σ ^* after correction: 1 / σ ^* (before correction)

  As described above, according to the fourth embodiment, in consideration of the boundary conditions on the sea surface and the sea bottom, a mirror image point current source (electrode) is virtually provided, and the electric field and mirror image point from the point current source on the ship are provided. The equation is set as the electric field generated by the ship with the sum of the electric field generated by the current source (electrode), and the parameter value is set so that the position estimation estimation unit 9b satisfies the value based on the electric field signal by applying the least square method. Since the current position and / or future position of the moving body moving on the sea surface and the sea is estimated and detected based on the determined value, it is possible to obtain a result that is closer to reality, and the position etc. accurately. Can be estimated and detected. Also, for ships navigating the sea surface, the depth of point current sources such as propellers and rudder changes depending on the size (displacement) of the ship (basically, the heavier it is, the deeper it is from the sea surface). Based on the parameter of the height of the point current source (distance with respect to the electric field detector 1 in the Z-axis direction), the size of the ship (the amount of drainage) can be estimated.

Embodiment 5 FIG.
In the first embodiment described above, a description has been given assuming that a plurality of point current sources (electrodes) are arranged in a line in the hull length direction. Here, for example, a case is considered in which a ship in which a plurality of point current sources are arranged in two rows of port and starboard (ship width direction) is considered. In this case, not only d _i which is a parameter in the hull length direction but also the next parameter d _wi is added. As a result, the theoretical formula can be made closer to the actual one, and the position and the like can be accurately estimated and detected.
d _wi : Spacing in the width direction of each point current source

Embodiment 6 FIG.
In the above-described fourth embodiment, the mirror image theory is applied to the theory based on the point current source and the theoretical formula is set. However, the present invention is not limited to this. For example, in the theory based on the dipole moment, as described in the fourth embodiment by applying mirror image theory, the theoretical formula is set using the sum of the electric field formulas of the mirror image point current sources from the dielectric constant of each medium. be able to. Also, in the case of detecting the magnetism as a signal and estimating and detecting the position or the like, the mirror image theory can be applied between media having different magnetic permeability to the theoretical formula for use in the method of least squares.

1 is a configuration block diagram of a moving body position detection device according to a first embodiment of the present invention. It is a figure showing the relationship between the position of a moving body and an electric field signal. It is a figure showing the relationship between a mobile body and a point current source. It is a figure showing the mirror image point current source (electrode) with respect to the point current source in a ship body.

Explanation of symbols

1 electric field detector, 2 magnetic detector, 3 tide meter, 4a, 4b, 4c A / D converter, 5 inclinometer, 6 induced electromotive force estimator, 7 electric field signal processor, 8 data collector, 8A data processing Part, 8B data recording part, 9 position etc. estimation detector, 9a electric field signal data correction part, 9b position etc. estimation detection part.

Claims (20)

At least the electric field and the seawater velocity are measured by the sensing and measuring means provided in the sea, and the seawater crosses the geomagnetism based on the velocity of the seawater and the measured or defined geomagnetic flux density data. Calculating a value based on the electromotive force;
And a step of removing a value component based on the induced electromotive force from the electric field. At least the electric field and the seawater speed are measured in time series by the detection and measurement means provided in the sea. Based on the seawater speed and the magnetic flux density data measured or determined, the seawater Calculating the value of the induced electromotive force generated by crossing the electric field, removing the component of the induced electromotive force from the electric field, and calculating the data of the electric field generated by the mobile body navigating the sea surface or the sea;
The estimation detection means applies a least square method using a residual to determine and determine parameter values such that the value of the electric field data generated by the moving body satisfies the theoretical formula relating to the point current source A method of estimating and detecting a position of the moving body, and the like, comprising: estimating and detecting at least a current and / or future position of the moving body based on the value of the parameter. At least the electric field and the seawater speed are measured in time series by the detection and measurement means provided in the sea. Based on the seawater speed and the magnetic flux density data measured or determined, the seawater Calculating the value of the induced electromotive force generated by crossing the electric field, removing the component of the induced electromotive force from the electric field, and calculating the data of the electric field generated by the mobile body navigating the sea surface or the sea;
The estimation detection means determines a value of a parameter that satisfies an expression represented by a sum of an electric field component generated by the moving body and an electric field component based on a mirror image electrode virtually set with a seawater surface and a sea bottom as a boundary, And a step of estimating and detecting at least the current and / or future position of the moving body based on the determined value of the parameter.   4. The method for estimating and detecting the position of a moving body according to claim 3, wherein values are further determined for parameters including electrical conductivity of seawater and the seabed. The method for estimating and detecting a moving object position or the like according to claim 2, wherein a Gauss-Newton method is applied to the least square method.   The method for estimating and detecting the position of a moving body according to any one of claims 2 to 5, further comprising the step of estimating and detecting a position closest to the speed of the moving body and a reception position of the signal of the electric field.   The method for estimating and detecting a moving object position or the like according to any one of claims 2 to 6, wherein the moving object or its type is determined based on the intensity of the electric field or the value of the parameter. An electric field detection means for detecting an electric field with each component in three axial directions;
Tidal current measuring means for measuring the velocity of seawater with each component in three axial directions;
Based on the data of each component of the magnetic flux density due to the velocity of the seawater and the measured or determined geomagnetism, induced electromotive force estimation means for performing calculation based on the generated induced electromotive force and generating electric field floating noise data,
An electric field detection apparatus comprising: electric field correction means for correcting data based on the electric field based on the electric field floating noise data. Magnetic field detection means for detecting a magnetic field with each component in three axial directions;
9. The electric field detection apparatus according to claim 8, wherein the induced electromotive force estimation means performs calculation based on data of each component of magnetic flux density by the geomagnetism based on the magnetic field. An electric field detection means for detecting an electric field with each component in three axial directions;
Tidal current measuring means for measuring the velocity of seawater with each component in three axial directions;
Based on the data of each component of the magnetic flux density due to the velocity of the seawater and the measured or determined geomagnetism, induced electromotive force estimation means for performing calculation based on the generated induced electromotive force and generating electric field floating noise data,
Data recording means for recording the electric field data detected by the electric field detection means and the electric field floating noise data in time series,
Electric field correction means for correcting data based on the electric field by the electric field floating noise data;
Iterative calculation by the least squares method using the residual until the electric field data corrected by the electric field correction means satisfies a predetermined convergence condition so that the electric field data of the point current source satisfies the theoretical formula And a detection means for estimating and detecting at least a current and / or future position of the mobile body based on the determined parameter value and performing the determination of a parameter value, etc. Estimated detection device. An electric field detection means for detecting an electric field with each component in three axial directions;
Tidal current measuring means for measuring the velocity of seawater with each component in three axial directions;
Based on the data of each component of the magnetic flux density due to the velocity of the seawater and the measured or determined geomagnetism, induced electromotive force estimation means for performing calculation based on the generated induced electromotive force and generating electric field floating noise data,
Data recording means for recording the electric field data detected by the electric field detection means and the electric field floating noise data in time series,
Electric field correction means for correcting data based on the electric field by the electric field floating noise data;
The value of the electric field data corrected by the electric field correcting means is based on a mirror image electrode virtually set with the boundary between the sea surface and the sea bottom as an electric field component directly emitted from a sea surface or a ship navigating in the sea as a moving body. A parameter value satisfying the expression expressed by the sum with the electric field component is determined by applying a least square method using a residual, and at least the current and / or the moving object is determined based on the determined parameter value. Alternatively, a moving body position estimation / detection device, comprising: a detection unit that estimates and detects a future position. Magnetic field detection means for detecting a magnetic field with each component in three axial directions;
The induced electromotive force estimating means, the moving body position or the like estimated detection apparatus according to claim 10 or 11, wherein the performing operations by the data of each component of the magnetic flux density due to the geomagnetism based on the magnetic field.
  The moving body position according to any one of claims 10 to 12, wherein the detecting means further estimates and detects the speed of the moving body and the closest approach position to the detecting means based on the value of the parameter. Equal estimation detection device.   The said detection means judges the said mobile body or its classification based on the magnitude | size of the said physical quantity, or the value of the said parameter, The detection detection etc. of a mobile body position in any one of Claims 10-12 characterized by the above-mentioned. apparatus. Based on the measured or defined magnetic flux density due to geomagnetism and the seawater velocity data obtained from means installed in the sea, the value based on the induced electromotive force generated by the seawater crossing the geomagnetism is calculated as data. Process,
A program for an electric field detection method, which causes a computer to calculate the electric field data corrected by removing the component of the value based on the induced electromotive force from the electric field data in the sea. Based on the measured or defined geomagnetic flux density and the seawater velocity data obtained from means installed in the sea, the value of the induced electromotive force generated by the seawater crossing the geomagnetism is calculated. Removing the component of the induced electromotive force from the electric field data, and calculating the electric field generated by the mobile body navigating the sea surface or the sea in time series as data;
By applying a least square method using a residual, a parameter value is determined so that the value of the electric field data generated by the moving body satisfies the theoretical formula relating to the point current source, and the determined parameter value A program for estimating and detecting a moving object position and the like, characterized by causing a computer to perform at least a step of estimating and detecting the current and / or future position of the moving object based on the computer program. Based on the measured or defined geomagnetic flux density and the seawater velocity data obtained from means installed in the sea, the value of the induced electromotive force generated by the seawater crossing the geomagnetism is calculated. Removing the component of the induced electromotive force from the electric field data, and calculating the electric field generated by the mobile body navigating the sea surface or the sea in time series as data;
Determining a value of a parameter that satisfies an expression represented by a sum of an electric field component generated by the moving body and an electric field component based on a mirror image electrode virtually set with a seawater surface and a sea bottom as a boundary;
A computer program for estimating and detecting a moving object position and the like, which causes a computer to perform at least a step of estimating and detecting a current and / or future position of the moving object based on the determined value of the parameter.   18. The program according to claim 17, wherein the computer further determines values for parameters including seawater and seabed electrical conductivity.   19. The computer according to claim 16, further causing the computer to perform estimation and detection of the closest position to the speed of the moving body and the reception position of the signal of the electric field based on the value of the parameter. A program for a method for detecting and detecting the position of a moving object. The mobile object position estimation detection method according to any one of claims 16 to 18, further causing a computer to make a determination of the mobile object or its type based on the intensity of the electric field or the value of the parameter. program.

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