Aircraft navigation and positioning method based on projection plane coordinate system

Abstract

The application provides an aircraft navigation positioning method based on a projection plane coordinate system, and relates to the technical field of aircraft navigation positioning. The method comprises the following steps: collecting initial latitude and longitude coordinates of an aircraft and a displacement vector of the aircraft in each sampling period, and converting the initial latitude and longitude coordinates into projection plane coordinates in a projection coordinate system; converting the displacement vector of the aircraft into a geographical displacement vector based on a current heading angle of the aircraft; calculating, in sequence, a transverse distance of the aircraft to a central meridian, a projection scale factor and a meridian convergence angle at a current time according to the projection plane coordinates and the current latitude of the aircraft at the current time; constructing a Jacobian compensation matrix based on the projection scale factor and the meridian convergence angle, and performing incremental calculation on the geographical displacement vector according to the Jacobian compensation matrix to update the projection plane coordinates of the aircraft. The application is helpful to improve the positioning reliability of the aircraft.

Description

Technical Field

[0001] This invention relates to the field of aircraft navigation and positioning technology, and in particular to an aircraft navigation and positioning method based on a projected plane coordinate system. Background Technology

[0002] In long-distance autonomous flight missions, navigation systems rely primarily on track estimation when GNSS signals are unavailable. Existing navigation algorithms typically assume that the flight area is an ideal Euclidean flat space, with the map coordinate system perfectly aligned with the physical motion space. They map the physical displacement measured by sensors to the map plane using only the heading angle. However, this approach often overlooks the nonlinear deformation caused by the projection of the Earth's ellipsoid onto the plane.

[0003] Chinese Patent Publication No. CN120976009A discloses an adaptive projection transformation method and related apparatus for low-altitude air navigation systems. The method involves acquiring decision factors for projection mode switching, including display scale and / or primary accuracy requirements; determining the target projection mode based on the decision factors; and transforming the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projected coordinates. Adaptive matching is performed based on the decision factors to determine the target projection mode, thereby transforming the acquired actual geographic coordinates according to the target projection mode to obtain the corresponding projected coordinates. However, the above scheme mainly relies on selecting the projection mode based on the display scale and primary accuracy requirements and performing a one-time coordinate transformation to handle projection distortion, resulting in continuous accumulation of scale distortion and orientation distortion errors during track calculation. Therefore, it is essential to provide an aircraft navigation and positioning method based on a projection plane coordinate system to improve the positioning reliability of aircraft. Summary of the Invention

[0004] In view of this, the present invention proposes an aircraft navigation and positioning method based on a projected plane coordinate system, which transforms the projected plane coordinate system into the basic space for navigation calculation, solves the problems of coordinate jump, repeated transformation and closed-loop cumulative error, thereby improving the positioning reliability of the aircraft.

[0005] This invention provides a method for aircraft navigation and positioning based on a projected plane coordinate system, the method comprising: The initial latitude and longitude coordinates of the aircraft and the displacement vector of the aircraft in each sampling period are collected. The Gauss-Kruger projection plane coordinate system is used as the basic coordinate space for the aircraft navigation calculation. The central meridian of the projection plane coordinate system is determined according to the initial longitude in the initial latitude and longitude coordinates, and the initial latitude and longitude coordinates are converted into projection plane coordinates under the projection coordinate system. Based on the current heading angle of the aircraft, the displacement vector of the aircraft in the carrier coordinate system is converted into the geographic displacement vector in the geographic coordinate system; Based on the projected plane coordinates and current latitude of the aircraft at the current moment, the lateral distance from the aircraft to the central meridian, the projection scale factor, and the meridian convergence angle at the current moment are calculated sequentially. Based on the projection scale factor and the meridian convergence angle, a Jacobian compensation matrix is ​​constructed, and the geographic displacement vector is incrementally calculated according to the Jacobian compensation matrix to update the projection plane coordinates corresponding to the aircraft.

[0006] Based on the above technical solutions, preferably, the step of converting the aircraft displacement vector in the carrier coordinate system to the geographic displacement vector in the geographic coordinate system based on the aircraft's current heading angle specifically includes: Based on the onboard sensors of the aircraft, the displacement vector of the aircraft in the carrier coordinate system is obtained in each sampling period, wherein the displacement vector of the aircraft includes an eastward displacement component along the nose direction and a northward displacement component along the right side of the fuselage. The current heading angle of the aircraft is collected, a rotation matrix from the carrier coordinate system to the geographic coordinate system is constructed based on the current heading angle, and the displacement vector of the aircraft is converted into a geographic displacement vector in the geographic coordinate system according to the rotation matrix.

[0007] Based on the above technical solutions, the preferred step of sequentially calculating the lateral distance, projection scale factor, and meridian convergence angle of the aircraft to the central meridian at the current moment specifically includes: Obtain the current projected plane coordinates of the aircraft and the current latitude of the aircraft in the geographic coordinate system; Based on the projected coordinate offset of the central meridian in the Gauss-Krüger projection coordinate system, calculate the lateral distance of the aircraft from the current position to the central meridian; Based on the lateral distance and the Earth's radius of curvature parameters, calculate the projection scale factor of the spacecraft at its current position; Based on the lateral distance, the current latitude, and the Earth's radius of curvature parameter, calculate the meridian convergence angle corresponding to the current position of the spacecraft.

[0008] More preferably, the step of incrementally calculating the geographic displacement vector based on the Jacobian compensation matrix to update the projected plane coordinates corresponding to the aircraft specifically includes: A Jacobian compensation matrix is ​​constructed using the projection scale factor as the scale compensation term and the meridian convergence angle as the direction compensation term. The Jacobian compensation matrix is ​​configured to linearly map the displacement increment vector in the geographic coordinate system to obtain the displacement increment vector in the projection plane coordinate system. The current projection coordinates are superimposed based on the displacement increment vector in the projection plane coordinate system to update the projection plane coordinates corresponding to the aircraft.

[0009] More preferably, the method further includes: The current longitude of the aircraft is obtained, and the differences between the current longitude and the left and right boundary longitudes of the adjacent projection zones are calculated respectively to determine the minimum longitude difference between the current longitude and the adjacent projection zones. The adjacent projection zones refer to the projection zones that are directly adjacent to the current projection zone of the aircraft in the longitude direction and share the same boundary meridian under the zoning rules of the Gauss-Kruger projection coordinate system. The minimum longitude difference is converted into the corresponding ground distance. When the ground distance is less than the projection zone switching distance threshold, the projection plane coordinates are solved in parallel solution mode to obtain the transition projection plane coordinates.

[0010] More preferably, the step of solving for the projection plane coordinates in a parallel solution mode specifically includes: In the first and second projection zones, the central meridian and corresponding projection parameters in their respective Gauss-Kruger projection coordinate systems are used to independently calculate the first projection plane coordinates of the aircraft in the first projection zone and the second projection plane coordinates of the aircraft in the second projection zone under the same sampling period. The first and second projection zones are adjacent projection zones, and the first projection zone is the projection zone in which the aircraft is currently located. The linear interpolation weight coefficient is determined based on the ratio between the ground distance and the projection zone switching distance threshold, and the first projection plane coordinates and the second projection plane coordinates are weighted and fused according to the linear interpolation weight coefficient to obtain the transition projection plane coordinates.

[0011] More preferably, the method further includes: When the aircraft fully enters the second projection zone and the ground distance between the aircraft and the first projection zone is greater than the projection zone switching distance threshold, only the standard projection plane coordinates under the second projection zone are retained to complete the projection zone switching.

[0012] A second aspect of this application provides a real-time positioning system for aircraft based on Jacobian matrix compensation for Gaussian projection distortion. The real-time positioning system includes a data acquisition module, a data processing module, and a coordinate positioning module. The data acquisition module is used to acquire the initial latitude and longitude coordinates of the aircraft and the displacement vector of the aircraft in each sampling period. The Gauss-Kruger projection plane coordinate system is used as the basic coordinate space for aircraft navigation calculation. The central meridian of the projection plane coordinate system is determined according to the initial longitude in the initial latitude and longitude coordinates, and the initial latitude and longitude coordinates are converted into projection plane coordinates under the projection coordinate system. The data processing module is used to convert the displacement vector of the aircraft in the carrier coordinate system into the geographic displacement vector in the geographic coordinate system based on the current heading angle of the aircraft. According to the projection plane coordinates and current latitude of the aircraft at the current moment, the lateral distance of the aircraft to the central meridian, the projection scale factor and the meridian convergence angle at the current moment are calculated in sequence. The coordinate positioning module is used to construct a Jacobian compensation matrix based on the projection scale factor and the meridian convergence angle, and to perform incremental calculations on the geographic displacement vector according to the Jacobian compensation matrix in order to update the projection plane coordinates corresponding to the aircraft.

[0013] A third aspect of this application provides an electronic device including a processor, a memory, a user interface, and a network interface, wherein the memory is used to store instructions, the user interface and the network interface are used to communicate with other devices, and the processor is used to execute the instructions stored in the memory.

[0014] A fourth aspect of this application provides a non-transitory computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor to implement the steps of an aircraft navigation and positioning method based on a projected plane coordinate system.

[0015] The aircraft navigation and positioning method based on a projected plane coordinate system provided by this invention has the following advantages over existing technologies: (1) By calculating the projection scale factor and meridian convergence angle based on the current latitude and lateral distance to the central meridian, and constructing the Jacobian compensation matrix, incremental correction is made for geographic displacement. This can compensate for the scaling and orientation distortions of the Gauss-Kruger projection, effectively reducing the positioning error caused by the transformation from the ellipsoid to the projection plane. Furthermore, the Jacobian compensation is dynamically updated in each sampling period under the current projection plane coordinates and current latitude, ensuring that the incremental update process always conforms to the local projection characteristics, suppressing the accumulation of projection distortion caused by displacement integral, and determining the central meridian and initial latitude based on the initial latitude and longitude. Instead of returning to the geodetic coordinates each time to perform a complete projection transformation, incremental updates are performed directly on the projection plane, reducing numerical instability and computational noise caused by multiple nonlinear coordinate transformations. This allows for higher consistency between geographic and projected displacements locally. By using the current heading angle to transform the displacement vector in the carrier coordinate system to the geographic coordinate system, and then combining it with the meridian convergence angle for projection correction, the direction and magnitude of displacement in the projection plane can still be accurately reflected even when the aircraft is maneuvering or its heading is changing rapidly. This improves the positioning reliability and trajectory continuity under complex flight conditions.

[0016] (2) By calculating the lateral distance from the aircraft to the central meridian in real time, and further obtaining the accurate projection scale factor and meridian convergence angle, the scale distortion and orientation distortion when converting geographic coordinates to projected coordinates can be quantitatively compensated. This is beneficial to improving the accuracy of the aircraft's position calculation in the projected coordinate system, reducing the track deviation caused by Gauss-Kruger projection distortion, and the real-time calculation of the meridian convergence angle allows the aircraft's heading angle to be accurately converted between the geographic coordinate system and the projected coordinate system, avoiding systematic errors in the heading angle caused by not considering meridian convergence. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating the aircraft navigation and positioning method based on a projected plane coordinate system provided by the present invention; Figure 2 A schematic diagram illustrating the theoretical distribution of the Gaussian projection scale factor as a function of longitude deviation, provided by this invention. Figure 3 A schematic diagram illustrating the relationship between the meridian convergence angle and latitude provided by the present invention; Figure 4The circular closed-loop route error elimination analysis diagram provided by the present invention; Figure 5 This is a schematic diagram of the structure of the real-time positioning system for aircraft provided by the present invention; Figure 6 This is a schematic diagram of the structure of the electronic device provided by the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. Real-time positioning system for aircraft; 11. Data acquisition module; 12. Data processing module; 13. Coordinate positioning module; 2. Electronic equipment; 21. Processor; 22. Communication bus; 23. User interface; 24. Network interface; 25. Memory. Detailed Implementation

[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] The following technical approaches are mainly used to address positioning errors caused by the Earth's curvature: Directly accumulating displacement in latitude and longitude space (LLA method): This method provides intuitive coordinates and clear physical meaning, but the physical distance corresponding to 1 degree of longitude varies with latitude, reaching only half the distance at the equator at 60° North latitude. Real-time cosine correction is required, and simple correction is only suitable for extremely short distances. When crossing large latitudes or in high-latitude regions, the nonlinearity caused by the convergence of meridians towards the poles leads to arc-shaped deviations in the trajectory due to linear accumulation; spherical geometric calculations are complex; and it is incompatible with electronic map systems based on projected coordinates.

[0022] The Earth-Centered, Earth-Fixed Coordinate System (ECEF) method uses a three-dimensional rectangular coordinate system. Its mathematical form is simple, and it has no singularities, yet its coordinate magnitude reaches 10^6. 6 The displacement increment is only 0.1 to 10 meters, and the scale span is 6 to 7 orders of magnitude, resulting in a loss of floating-point precision; using 3D ellipsoidal transformation is highly complex and disconnected from two-dimensional maps.

[0023] Local tangent plane approximation (ENU method): This method is computationally simple and naturally aligned with the IMU, but it attempts to simulate a "curved sphere" with an "absolute plane", which has a limited effective range (10-20km). Long-distance flights require resetting the tangent point, causing coordinate jumps; it cannot provide a globally consistent coordinate framework.

[0024] This invention discloses an aircraft navigation and positioning method based on a projected plane coordinate system, with reference to... Figure 1The steps of this method include S1 to S4.

[0025] Step S1: Collect the initial latitude and longitude coordinates of the aircraft and the displacement vector of the aircraft in each sampling period. Use the Gauss-Kruger projection plane coordinate system as the basic coordinate space for aircraft navigation calculation. Determine the central meridian of the projection plane coordinate system based on the initial longitude in the initial latitude and longitude coordinates, and convert the initial latitude and longitude coordinates into projection plane coordinates under the projection coordinate system.

[0026] In this step, the Gauss-Kruger projection plane coordinate system is used as the basic coordinate space for aircraft navigation calculation, and the aircraft displacement is continuously updated by incremental integration within the projection plane coordinate system. First, the initial latitude and longitude coordinates of the aircraft are acquired, and the central meridian of the projection plane coordinate system is determined based on the initial longitude, converting the initial latitude and longitude coordinates into initial projected coordinates. During subsequent navigation, the displacement is directly incrementally integrated within the projection plane coordinate system to update the projection plane coordinates, without returning to the latitude and longitude or local tangent plane coordinate system for calculation.

[0027] In one example, due to the Gaussian projection unfolding the ellipsoid onto a plane, there is a scale factor *m* that deviates between the map distance and the actual ground distance. This factor is defined as:

[0028]

[0029] According to Gaussian projection theory, we know that:

[0030] in, This represents the distance from the point to the projection plane of the central meridian. This represents the projected coordinates of a point along the central meridian, where R represents the Earth's mean radius of curvature, approximately 6,371,008.8 meters. Indicates latitude, Represents a higher-order small term, i.e., a term that follows... And the ignored terms that change to higher powers.

[0031] In practical applications, the second term can usually be ignored; simplified engineering form:

[0032] like Figure 2 As shown, the variation law of the scale factor of Gauss projection in different latitudinal regions was verified through theoretical calculations and numerical simulations. First, the actual physical flight distance under the WGS84 ellipsoid was used as the reference value; then, the starting and ending points of the flight distance were converted into plane coordinates using the Gauss-Kruger projection, and their two-dimensional Euclidean distance was calculated; by the difference between the two, the deviation of the inertial odometry system caused by the projection scale factor can be accurately quantified.

[0033] Figure 2 The upper part shows the theoretical distribution of the scale factor *m* with distance from the central meridian, while the lower part further quantifies the actual impact of this deformation on inertial odometers. Taking Haikou as an example, at a distance of 1.5° from the central meridian, due to the scale factor... The deviation increases quadratically with longitude, resulting in a geometric stretching error of approximately 15.18 meters on the projected surface for every 50 kilometers of flight distance.

[0034] It can be seen that the scale factor changes nonlinearly with different geographical locations and cannot be compensated by a fixed value. The existing single projection parameter cannot adapt to different latitudinal regions. An adaptive compensation coefficient must be introduced to eliminate projection distortion. In the zone edge region 1.5 degrees away from the central meridian, the scale distortion in low-latitude areas is more significant, requiring an adaptive correction strategy.

[0035] In this step, the initial latitude and longitude are obtained. ,in, Indicates latitude, Indicates longitude, based on longitude Automatically identify the central meridian in the current Gauss-Kruger projection 3-degree zone coordinate system. The longitude of the central meridian is expressed as:

[0036] in, This represents the longitude of the central meridian in the current Gauss-Kruger projection 3-degree zone coordinate system. This indicates a bandwidth of 3°. This represents the floor function.

[0037] Using the Gaussian projection forward calculation formula, the initial latitude and longitude are calculated. Convert to initial projection plane coordinates ,in, Indicates the east coordinate. Indicates the north coordinate.

[0038] Step S2: Based on the aircraft's current heading angle, convert the aircraft displacement vector in the carrier coordinate system into a geographic displacement vector in the geographic coordinate system.

[0039] This step also includes steps S21 to S22.

[0040] Step S21: Based on the aircraft's onboard sensors, obtain the aircraft displacement vector in the carrier coordinate system for each sampling period. The aircraft displacement vector includes an eastward displacement component along the nose direction and a northward displacement component along the right side of the fuselage.

[0041] In this step, during the sampling period Obtain the displacement vector in the carrier coordinate system:

[0042] in, Indicates the sampling period Obtain the displacement vector in the carrier coordinate system. Indicates the displacement in the direction of the nose. This indicates the displacement in the right direction of the fuselage.

[0043] Step S22: Collect the current heading angle of the aircraft, construct a rotation matrix from the carrier coordinate system to the geographic coordinate system based on the current heading angle, and convert the aircraft displacement vector into a geographic displacement vector in the geographic coordinate system according to the rotation matrix.

[0044] In this step, the current heading angle is obtained. The displacement in the carrier coordinate system is converted to the displacement in the geographic coordinate system by using a rotation matrix:

[0045] in, Represents the geographic displacement vector in a geographic coordinate system. Indicates eastward displacement. This indicates northward displacement.

[0046] Step S3: Based on the projected plane coordinates and current latitude of the aircraft at the current moment, calculate the lateral distance from the aircraft to the central meridian, the projection scale factor, and the meridian convergence angle at the current moment.

[0047] In one example, the meridian convergence angle γ is defined as the angle between the map coordinate vertical axis (coordinate north) and the geographic true north direction. Based on projection geometry:

[0048]

[0049] Simplified engineering form (small angle approximation):

[0050] like Figure 3 As shown, this paper systematically analyzes the impact of the meridian convergence angle on the azimuth estimation of inertial odometry in existing technologies. First, the aircraft is assumed to travel in a straight line along true geographic north (true north) under the WGS84 ellipsoid, using this physical trajectory as a reference value. Then, the coordinates of the starting and ending points of this trajectory are converted to Cartesian coordinates using the Gauss-Kruger projection. By calculating the deviation angle of the line connecting two points on the projection plane relative to the map coordinate north, and converting it into a lateral displacement deviation, the cumulative azimuth error caused by the meridian convergence angle can be accurately quantified. This deviation manifests on the projection plane as a lateral position drift that increases linearly with the flight distance.

[0051] Figure 3 The upper part shows the convergence angle γ and latitude. Theoretical relationship At 1.5° of the zone boundary, the convergence angle increases from low to high latitudes. The lower part reveals the cumulative azimuth error caused by this angular deviation over a 10-50 km journey from south to north:

[0052] Haikou area (20°N): lateral drift of 452.77m over a 50km range, drift rate of 9.06 m / km; Harbin area (45°N): 50km range, lateral drift of 929.44m, drift rate of 18.59 m / km; Arctic Circle region (66.5°N): lateral drift of 1202.45m over a 50km voyage, drift rate of 24.05 m / km; The sensitivity of azimuth error is significantly higher in high-latitude regions than in low-latitude regions. The convergence angle varies with latitude and longitude, and azimuth error can cause lateral deviation of the flight track, which accumulates linearly.

[0053] This step also includes steps S31 to S34.

[0054] Step S31: Obtain the current projection plane coordinates of the aircraft and the current latitude of the aircraft in the geographic coordinate system.

[0055] In this step, the current projection plane coordinates of the aircraft are obtained. and current latitude and longitude coordinates .

[0056] Step S32: Calculate the lateral distance from the aircraft to the central meridian at its current position based on the projected coordinate offset of the central meridian in the Gauss-Kruger projection coordinate system.

[0057] In this step, the lateral distance of the aircraft from its current position to the central meridian can be expressed as:

[0058] in, This indicates the lateral distance of the aircraft from its current position to the central meridian. This represents the x-coordinate in the current projected plane coordinate system of the aircraft. This represents the projected coordinate offset, typically 500,000 meters.

[0059] Step S33: Calculate the projection scale factor of the spacecraft at its current position based on the lateral distance and the Earth's radius of curvature parameters.

[0060] In this step, the projection scale factor corresponding to the aircraft's current position can be expressed as:

[0061] in, This represents the projection scale factor of the aircraft at its current position. R represents the lateral distance of the spacecraft from its current position to the central meridian, and R represents the Earth's mean radius of curvature.

[0062] Step S34: Based on the lateral distance, current latitude, and Earth's radius of curvature, calculate the meridian convergence angle corresponding to the spacecraft's current position.

[0063] In this step, the meridian convergence angle corresponding to the aircraft's current position is determined. It can be represented as:

[0064] in, This represents the latitude in the current latitude and longitude coordinate system. When | When | < 0.1 radians, a small angle approximation can be used.

[0065] In this embodiment, by calculating the lateral distance from the aircraft to the central meridian in real time, and further obtaining the accurate projection scale factor and meridian convergence angle, the scale distortion and orientation distortion when converting geographic coordinates to projected coordinates are quantitatively compensated. This helps to improve the accuracy of the aircraft's position calculation in the projected coordinate system, reduce the track deviation caused by Gauss-Kruger projection distortion, and the real-time calculation of the meridian convergence angle allows the aircraft's heading angle to be accurately converted between the geographic coordinate system and the projected coordinate system, avoiding systematic errors in the heading angle caused by not considering meridian convergence.

[0066] Step S4: Based on the projection scale factor and the meridian convergence angle, construct the Jacobian compensation matrix, and perform incremental calculation on the geographic displacement vector according to the Jacobian compensation matrix to update the projection plane coordinates corresponding to the aircraft.

[0067] This step also includes steps S41 to S43.

[0068] Step S41: Construct the Jacobian compensation matrix using the projection scale factor as the scale compensation term and the meridian convergence angle as the direction compensation term.

[0069] In one example, the Jacobian compensation matrix acts as a bridge connecting the "sensor physical observation space" and the "map projection coordinate space," constructing a Jacobian matrix that dynamically changes with geographical location to achieve a precise differential mapping from the physical motion space to the map projection space. In latitude and longitude... At this point, the compensation matrix is ​​constructed as follows:

[0070]

[0071] Isotropic scale term This compensates for the proportional deviation between the "map distance" and the "actual physical distance on the ground" caused by projection surface stretching. Rotation compensation component. By rotating and transforming, the angular deviation between "Geographic True North" and "Projected Coordinate North" is corrected in real time, i.e., the meridian convergence angle.

[0072] From the perspective of differential geometry, the Jacobian matrix This describes the tangential mapping from the physical motion manifold to the planar projected manifold. During navigation calculations, the sensor acquires the infinitesimal displacement vector in the true north-east coordinate system. It is not directly equal to the coordinate increment of the projection plane. It is determined through the operator. The vector is reconstructed to obtain the corrected planar coordinate increments. Represented as:

[0073]

[0074] This precise mapping with micro-levels ensures that the displacement increment of each control cycle can be correctly reproduced on the projection plane, thereby cutting off the nonlinear accumulation path of system error at its source.

[0075] In this step, a 2x2 Jacobian compensation matrix is ​​constructed.

[0076] This matrix contains two layers of coupled corrections and rotation components. Used to compensate for the angular deviation between coordinate north and true north, scale component Used to compensate for the ratio deviation between map distance and ground distance.

[0077] Step S42: Configure the Jacobian compensation matrix to linearly map the displacement increment vector in the geographic coordinate system to obtain the displacement increment vector in the projected plane coordinate system.

[0078] In this step, the physical displacement is transformed using a Jacobian transformation to obtain the displacement increment in the projected coordinate system:

[0079] in, This represents the displacement increment of the east coordinate system in the projection plane coordinate system. This represents the displacement increment of the north coordinate in the projected plane coordinate system.

[0080] Step S43: Based on the displacement increment vector in the projection plane coordinate system, the current projection coordinates are superimposed to update the projection plane coordinates corresponding to the aircraft.

[0081] In this step, the process of updating the coordinates of the corresponding projection plane of the aircraft can be represented as:

[0082]

[0083] The process of updating the latitude of an aircraft can be represented as:

[0084] in, Indicates the current projection plane coordinates of the aircraft. This represents the projected plane coordinates of the spacecraft at the next moment. This indicates the latitude of the spacecraft at the next moment.

[0085] In one example, the current longitude of the aircraft is obtained, and the differences between the current longitude and the left and right boundary longitudes of the adjacent projection zones are calculated to determine the minimum longitude difference between the current longitude and the adjacent projection zones. The adjacent projection zones refer to the projection zones that are directly adjacent to the current projection zone of the aircraft in the longitude direction and share the same boundary meridian under the zoning rules of the Gauss-Kruger projection coordinate system.

[0086] The minimum longitude difference is converted into the corresponding ground distance. When the ground distance is less than the projection zone switching distance threshold, the projection plane coordinates are solved in parallel solution mode to obtain the transition projection plane coordinates.

[0087] Furthermore, in the first and second projection zones, the central meridian and corresponding projection parameters in their respective Gauss-Kruger projection coordinate systems are used to independently calculate the first projection plane coordinates of the aircraft in the first projection zone and the second projection plane coordinates of the aircraft in the second projection zone under the same sampling period. The first and second projection zones are adjacent projection zones, and the first projection zone is the projection zone in which the aircraft is currently located. The linear interpolation weight coefficient is determined based on the ratio between the ground distance and the projection zone switching distance threshold, and the coordinates of the first projection plane and the second projection plane are weighted and fused according to the linear interpolation weight coefficient to obtain the coordinates of the transition projection plane.

[0088] Furthermore, monitor the current longitude. Whether it is close to the boundary of the projection zone can be expressed as:

[0089] in, This represents the minimum difference in longitude between the current longitude and the boundaries of the left and right zones. This indicates the minimum value operation. This indicates the longitude of the left boundary of the current projection zone. This indicates the longitude of the right boundary of the current projection zone. This indicates the current longitude of the aircraft.

[0090] when When calculating the longitude difference corresponding to 1 kilometer, the parallel solution mode is enabled, and the coordinates of the current zone (Zone N) are calculated simultaneously. and the coordinates of adjacent zones (Zone N±1) . This indicates the threshold for switching the projection band distance.

[0091] Coordinate fusion is performed using linear weights based on a distance-weighted average.

[0092]

[0093]

[0094] in, This represents the linear interpolation weighting coefficient.

[0095] When the aircraft fully enters the second projection zone and the ground distance between the aircraft and the first projection zone is greater than the projection zone switching distance threshold, only the standard projection plane coordinates under the second projection zone are retained to complete the projection zone switching.

[0096] In this embodiment, the projection scale factor and meridian convergence angle are calculated based on the current latitude and lateral distance to the central meridian, and a Jacobian compensation matrix is ​​constructed to incrementally correct geographical displacement. This compensates for the scaling and orientation distortions of the Gauss-Kruger projection, effectively reducing positioning errors caused by the transformation from the ellipsoid to the projection plane. Furthermore, the Jacobian compensation is dynamically updated in each sampling period under the current projection plane coordinates and current latitude, ensuring that the incremental update process always conforms to the local projection characteristics, suppressing the accumulation of projection distortion caused by displacement integrals, and determining the central meridian using the initial latitude and longitude. Instead of returning to the geodetic coordinates each time to perform a complete projection transformation, incremental updates are performed directly on the projection plane based on the initial projection coordinates. This reduces numerical instability and computational noise caused by multiple nonlinear coordinate transformations, and makes the geographic displacement and projected displacement more consistent locally. By using the current heading angle to transform the displacement vector in the carrier coordinate system to the geographic coordinate system, and then combining it with the meridian convergence angle for projection correction, the direction and magnitude of the displacement in the projection plane can still be accurately reflected when the aircraft maneuvers and the heading changes rapidly. This improves the positioning reliability and trajectory continuity under complex flight conditions.

[0097] In one example, a closed-loop flight path is a standard method for verifying the global accuracy of a navigation system in aerial surveying. Closure error (position deviation upon returning to the starting point) directly reflects the system's error accumulation characteristics during long-endurance operations and is a key indicator for evaluating navigation accuracy. By setting error checkpoints at key locations during a 100km circular flight test, the error control capability of the Jacobian matrix compensation method in long-endurance operations can be comprehensively evaluated. When the aircraft returns to the starting point along the closed-loop flight path, the accumulated positioning error generated by navigation integration in the projected plane coordinate system approaches zero. Error self-cancellation is achieved through the following mechanism:

[0098] At different locations along the closed path, the magnification and reduction effects of the projection scale factor cancel each other out. In different heading segments, the positive and negative deviations of the meridian convergence angle cancel each other out; By updating the Jacobi compensation matrix in real time, the aforementioned cancellation is ensured to occur naturally in the incremental integral.

[0099] Furthermore, a multi-directional closed-loop verification embodiment was designed, with typical low-altitude aerial survey scenario parameters as follows: Test location: Harbin area (45° North latitude); Projection system: Gauss-Kruger projection, 3-degree zone, central meridian 126°E; Projection position: 1.5° from the central meridian (located at the edge of the projection zone, where distortion effects are significant); Route design: Square closed route, first segment: 25 km due north, second segment: 25 km due east, third segment: 25 km due south, fourth segment: 25 km due west, total distance: 100 km.

[0100] Please see Figure 4 The simulation verification method is adopted, by constructing a dynamic Jacobian matrix. The system can transmit the physical displacement measured by the sensors in real time. Precise mapping to map coordinate increments The rotation component of the matrix compensates for angular deviations, while the scaling component compensates for scaling ratios, thus eliminating the cumulative error after the corners of the polygonal line. Test results are as follows... Figure 4 As shown.

[0101] Under the traditional uncompensated method, the systematic error accumulates continuously with the flight distance, exhibiting obvious direction dependence and nonlinear growth characteristics. Details of the errors at key points are shown in Table 1.

[0102] Table 1

[0103] The error characteristics of the four flight segments in Table 1 are as follows: Northbound segment (0-25km): Due to projection distortion, when flying due north on the projection plane, the actual ground trajectory shifts westward, with the lateral error accumulating to 463.9 meters at 25km.

[0104] Eastbound segment (25-50km): At this point, the latitude has increased from 45.0° to 45.225°, and the longitude scale has decreased. Flying 25km eastward on the projected plane, the actual longitude traversed by the geodetic trajectory is greater, leading to further accumulation of errors, reaching a maximum of 642.0 meters at 50km.

[0105] Southbound segment (50-75km): When flying south, the latitude gradually decreases and the longitude scale gradually increases, and the nature of the error changes. At 75km, the error is 549.4 meters.

[0106] Westward segment (75-100km): After returning to the starting latitude, the flight heads west, but due to the accumulated deviation of the previous segment, it cannot return to the starting point completely, resulting in a closure error of 99.1 meters and a closure error rate of 0.099%.

[0107] After using Jacobian matrix real-time compensation, the system error was significantly suppressed. A comparison of key technical indicators is shown in Table 2.

[0108] Table 2

[0109] Under theoretical conditions—namely, no sensor noise and real-time accurate calculation of the Jacobian matrix—this method can theoretically completely eliminate systematic errors caused by projection distortion. However, in practical applications, the residuals mainly originate from: sensor measurement noise (such as drift error in inertial navigation systems), limitations on the Jacobian matrix update frequency (typically 10-100Hz), and limitations on numerical calculation accuracy (floating-point operation error of approximately 10). -14 (Order of magnitude) and the accuracy limitations of ellipsoidal and projection parameters.

[0110] When flying over a true square in a geodetic coordinate system, the longitude scale varies significantly at different latitudes due to the Earth's curvature and latitude variations. Specifically:

[0111] When the starting latitude is 45.0°, the longitude scale coefficient is cos(45.0°)≈0.7071; Flying 25km north, the latitude is 45.225°, and the longitude scale coefficient is cos(45.225°)≈0.7055; The difference between the two is approximately 0.23%.

[0112] Theoretical estimation of closure error: Longitude deviation due to latitude variation: approximately 57.5 meters, affected by a span of 25km. The impact of proportional differences.

[0113] Projection scale distortion effect: approximately 15 meters, affected by the average scale factor in the east-west flight segment. The stretching effect.

[0114] The dynamic deviation of the meridian convergence angle is approximately 27 meters, which is caused by the cumulative azimuth shift resulting from the change of the 1.06° convergence angle with the latitude gradient.

[0115] The cumulative geometric distortions mentioned above amount to approximately 99 meters.

[0116] Clearly, the Jacobian matrix compensation method, based on rigorous differential geometry theory, can mathematically and accurately model the local linearization characteristics of map projection. Under theoretical limits, this method can completely eliminate systematic errors caused by projection distortion, which is unattainable by traditional fixed-attitude matrix methods. During a 100km flight across four different directions, the compensated systematic error theoretically remained zero, showing no significant accumulation trend. This demonstrates the stability of the method in long-term, large-scale operations. The compensation effect remained consistent regardless of the flight direction (north, east, south, or west). This proves that the Jacobian matrix can accurately model the projection distortion characteristics in all directions and exhibits good isotropy. The entire compensation process can be completed in real-time during flight, with low computational complexity and no need for post-flight data processing, meeting the requirements of real-time navigation operations. This method does not rely on high-precision map data and requires minimal storage space; it only needs the latitude and longitude of the current location and projection parameters to calculate the Jacobian matrix in real time. This makes the method highly feasible and portable in engineering. The closed-loop flight path test, spanning 100 kilometers and encompassing four directions, has been fully validated, demonstrating that the Jacobian matrix compensation method can theoretically and completely eliminate systematic errors caused by projection distortion. This method possesses significant advantages, including theoretical completeness, high accuracy, good real-time performance, and engineering feasibility, and can be widely applied in fields such as aerial surveying, aircraft navigation, and precision agriculture.

[0117] Based on the above method, this application discloses a real-time positioning system for aircraft based on Jacobian matrix compensation for Gaussian projection distortion, with reference to... Figure 5 The real-time positioning system 1 for aircraft includes a data acquisition module 11, a data processing module 12, and a coordinate positioning module 13, wherein... The data acquisition module 11 is used to acquire the initial latitude and longitude coordinates of the aircraft and the displacement vector of the aircraft in each sampling period. The Gauss-Kruger projection plane coordinate system is used as the basic coordinate space for the aircraft navigation calculation. The central meridian of the projection plane coordinate system is determined according to the initial longitude in the initial latitude and longitude coordinates, and the initial latitude and longitude coordinates are converted into projection plane coordinates under the projection coordinate system. The data processing module 12 is used to convert the aircraft displacement vector in the carrier coordinate system into the geographic displacement vector in the geographic coordinate system based on the aircraft's current heading angle. According to the aircraft's projection plane coordinates and current latitude at the current moment, it sequentially calculates the lateral distance of the aircraft to the central meridian, the projection scale factor, and the meridian convergence angle at the current moment. The coordinate positioning module 13 is used to construct the Jacobian compensation matrix based on the projection scale factor and the meridian convergence angle, and to perform incremental calculations on the geographic displacement vector according to the Jacobian compensation matrix in order to update the projection plane coordinates corresponding to the aircraft.

[0118] In one example, the data processing module 12 is used to acquire the aircraft displacement vector in the carrier coordinate system in each sampling period based on the aircraft's onboard sensors. The aircraft displacement vector includes an eastward displacement component along the nose direction and a northward displacement component along the right side of the fuselage. The module also acquires the aircraft's current heading angle, constructs a rotation matrix from the carrier coordinate system to the geographic coordinate system based on the heading angle, and converts the aircraft displacement vector into a geographic displacement vector in the geographic coordinate system based on the rotation matrix.

[0119] In one example, the data processing module 12 is used to obtain the current projection plane coordinates of the aircraft and the current latitude of the aircraft in the geographic coordinate system; calculate the lateral distance of the aircraft from the central meridian to the central meridian based on the projection coordinate offset of the central meridian in the Gauss-Kruger projection coordinate system; calculate the projection scale factor of the aircraft at the current position based on the lateral distance and the radius of curvature of the earth; and calculate the meridian convergence angle of the aircraft at the current position based on the lateral distance, the current latitude, and the radius of curvature of the earth.

[0120] In one example, the coordinate positioning module 13 is used to construct a Jacobian compensation matrix using the projection scale factor as the scale compensation term and the meridian convergence angle as the direction compensation term; the Jacobian compensation matrix is ​​configured to linearly map the displacement increment vector in the geographic coordinate system to obtain the displacement increment vector in the projection plane coordinate system; and the current projection coordinates are superimposed based on the displacement increment vector in the projection plane coordinate system to update the projection plane coordinates corresponding to the aircraft.

[0121] In one example, the method also includes: Obtain the current longitude of the aircraft and calculate the differences between the current longitude and the left and right boundary longitudes of the adjacent projection zones to determine the minimum longitude difference between the current longitude and the adjacent projection zones. The adjacent projection zones refer to the projection zones that are directly adjacent to the current projection zone of the aircraft in the longitude direction and share the same boundary meridian under the zoning rules of the Gauss-Kruger projection coordinate system. The minimum longitude difference is converted into the corresponding ground distance. When the ground distance is less than the projection zone switching distance threshold, the projection plane coordinates are solved in parallel solution mode to obtain the transition projection plane coordinates.

[0122] In one example, the coordinates of the projected plane are solved in parallel, specifically including: In the first and second projection zones, the central meridian and corresponding projection parameters in their respective Gauss-Kruger projection coordinate systems are used to independently calculate the first projection plane coordinates of the aircraft in the first projection zone and the second projection plane coordinates of the aircraft in the second projection zone under the same sampling period. The first and second projection zones are adjacent projection zones, and the first projection zone is the projection zone in which the aircraft is currently located. The linear interpolation weight coefficient is determined based on the ratio between the ground distance and the projection zone switching distance threshold, and the coordinates of the first projection plane and the second projection plane are weighted and fused according to the linear interpolation weight coefficient to obtain the coordinates of the transition projection plane.

[0123] In one example, the method further includes: when the aircraft fully enters the second projection zone and the ground distance between the aircraft and the first projection zone is greater than the projection zone switching distance threshold, only the standard projection plane coordinates under the second projection zone are retained to complete the projection zone switching.

[0124] Please see Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 6 As shown, the electronic device 2 may include: at least one processor 21, at least one network interface 24, user interface 23, memory 25, and at least one communication bus 22.

[0125] The communication bus 22 is used to enable communication between these components.

[0126] The user interface 23 may include a display screen and a camera. Optionally, the user interface 23 may also include a standard wired interface and a wireless interface.

[0127] The network interface 24 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface).

[0128] The processor 21 may include one or more processing cores. The processor 21 connects to various parts of the server using various interfaces and lines, and performs various server functions and processes data by running or executing instructions, programs, code sets, or instruction sets stored in the memory 25, and by calling data stored in the memory 25. Optionally, the processor 21 may be implemented using at least one hardware form of Digital Signal Processing (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 21 may integrate one or a combination of several of the following: Central Processing Unit (CPU), Graphics Processing Unit (GPU), and modem. The CPU primarily handles the operating system, user interface, and applications; the GPU is responsible for rendering and drawing the content required for display; and the modem handles wireless communication. It is understood that the modem may also be implemented as a separate chip without being integrated into the processor 21.

[0129] The memory 25 may include random access memory (RAM) or read-only memory. Optionally, the memory 25 may include non-transitory computer-readable storage medium. The memory 25 can be used to store instructions, programs, code, code sets, or instruction sets. The memory 25 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as touch function, sound playback function, image playback function, etc.), instructions for implementing the above-described method embodiments, etc.; the data storage area may store data involved in the above-described method embodiments, etc. Optionally, the memory 25 may also be at least one storage device located remotely from the aforementioned processor 21. Figure 6 As shown, the memory 25, which serves as a computer storage medium, may include an operating system, a network communication module, a user interface module, and an application program for an aircraft navigation and positioning method based on a projected plane coordinate system.

[0130] exist Figure 6In the electronic device 2 shown, the user interface 23 is mainly used to provide an input interface for the user and to obtain the user input data; while the processor 21 can be used to call an application program stored in the memory 25 that is a method for aircraft navigation and positioning based on a projected plane coordinate system. When executed by one or more processors, the electronic device executes one or more methods as described in the above embodiments.

[0131] A non-transitory computer-readable storage medium stores instructions that, when executed by one or more processors, cause a computer to perform one or more methods as described in the above embodiments.

[0132] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0133] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0134] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the shown or discussed mutual couplings or direct couplings or communication connections may be through some service interfaces; indirect couplings or communication connections between apparatuses or units may be electrical or other forms.

[0135] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0136] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0137] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, portable hard drives, magnetic disks, or optical disks.

[0138] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for aircraft navigation and positioning based on a projected plane coordinate system, characterized in that, The method includes: The initial latitude and longitude coordinates of the aircraft and the displacement vector of the aircraft in each sampling period are collected. The Gauss-Kruger projection plane coordinate system is used as the basic coordinate space for the aircraft navigation calculation. The central meridian of the projection plane coordinate system is determined according to the initial longitude in the initial latitude and longitude coordinates, and the initial latitude and longitude coordinates are converted into projection plane coordinates under the projection coordinate system. Based on the current heading angle of the aircraft, the displacement vector of the aircraft in the carrier coordinate system is converted into the geographic displacement vector in the geographic coordinate system; Based on the projected plane coordinates and current latitude of the aircraft at the current moment, the lateral distance from the aircraft to the central meridian, the projection scale factor, and the meridian convergence angle at the current moment are calculated sequentially. Based on the projection scale factor and the meridian convergence angle, a Jacobian compensation matrix is ​​constructed, and the geographic displacement vector is incrementally calculated according to the Jacobian compensation matrix to update the projection plane coordinates corresponding to the aircraft.

2. The aircraft navigation and positioning method based on a projected plane coordinate system as described in claim 1, characterized in that, The process of converting the aircraft displacement vector in the carrier coordinate system to the geographic displacement vector in the geographic coordinate system based on the aircraft's current heading angle specifically includes: Based on the airborne sensors of the aircraft, the displacement vector of the aircraft in the carrier coordinate system is obtained in each sampling period, wherein the displacement vector of the aircraft includes an eastward displacement component along the nose direction and a northward displacement component along the right side of the fuselage. The current heading angle of the aircraft is collected, a rotation matrix from the carrier coordinate system to the geographic coordinate system is constructed based on the current heading angle, and the displacement vector of the aircraft is converted into a geographic displacement vector in the geographic coordinate system according to the rotation matrix.

3. The aircraft navigation and positioning method based on a projected plane coordinate system as described in claim 1, characterized in that, The sequential calculation of the lateral distance from the aircraft to the central meridian at the current moment, the projection scale factor, and the meridian convergence angle specifically includes: Obtain the current projected plane coordinates of the aircraft and the current latitude of the aircraft in the geographic coordinate system; Based on the projected coordinate offset of the central meridian in the Gauss-Krüger projection coordinate system, calculate the lateral distance of the aircraft from the current position to the central meridian; Based on the lateral distance and the Earth's radius of curvature parameters, calculate the projection scale factor of the spacecraft at its current position; Based on the lateral distance, the current latitude, and the Earth's radius of curvature parameter, calculate the meridian convergence angle corresponding to the current position of the spacecraft.

4. The aircraft navigation and positioning method based on a projected plane coordinate system as described in claim 1, characterized in that, The step of incrementally calculating the geographic displacement vector based on the Jacobian compensation matrix to update the projected plane coordinates of the aircraft specifically includes: A Jacobian compensation matrix is ​​constructed using the projection scale factor as the scale compensation term and the meridian convergence angle as the direction compensation term. The Jacobian compensation matrix is ​​configured to linearly map the displacement increment vector in the geographic coordinate system to obtain the displacement increment vector in the projection plane coordinate system. The current projection coordinates are superimposed based on the displacement increment vector in the projection plane coordinate system to update the projection plane coordinates corresponding to the aircraft.

5. The aircraft navigation and positioning method based on a projected plane coordinate system as described in claim 1, characterized in that, The method further includes: The current longitude of the aircraft is obtained, and the differences between the current longitude and the left and right boundary longitudes of the adjacent projection zones are calculated respectively to determine the minimum longitude difference between the current longitude and the adjacent projection zones. The adjacent projection zones refer to the projection zones that are directly adjacent to the current projection zone of the aircraft in the longitude direction and share the same boundary meridian under the zoning rules of the Gauss-Kruger projection coordinate system. The minimum longitude difference is converted into the corresponding ground distance. When the ground distance is less than the projection zone switching distance threshold, the projection plane coordinates are solved in parallel solution mode to obtain the transition projection plane coordinates.

6. The aircraft navigation and positioning method based on a projected plane coordinate system as described in claim 5, characterized in that, The method of solving for the coordinates of the projection plane using a parallel solution mode specifically includes: In the first and second projection zones, the central meridian and corresponding projection parameters in their respective Gauss-Kruger projection coordinate systems are used to independently calculate the first projection plane coordinates of the aircraft in the first projection zone and the second projection plane coordinates of the aircraft in the second projection zone under the same sampling period. The first and second projection zones are adjacent projection zones, and the first projection zone is the projection zone in which the aircraft is currently located. The linear interpolation weight coefficient is determined based on the ratio between the ground distance and the projection zone switching distance threshold, and the first projection plane coordinates and the second projection plane coordinates are weighted and fused according to the linear interpolation weight coefficient to obtain the transition projection plane coordinates.

7. The aircraft navigation and positioning method based on a projected plane coordinate system as described in claim 6, characterized in that, The method further includes: When the aircraft fully enters the second projection zone and the ground distance between the aircraft and the first projection zone is greater than the projection zone switching distance threshold, only the standard projection plane coordinates under the second projection zone are retained to complete the projection zone switching.

8. A real-time positioning system for aircraft based on Jacobian matrix compensation for Gaussian projection distortion, characterized in that, The real-time positioning system (1) for the aircraft includes a data acquisition module (11), a data processing module (12), and a coordinate positioning module (13), wherein, The data acquisition module (11) is used to acquire the initial latitude and longitude coordinates of the aircraft and the displacement vector of the aircraft in each sampling period, and to use the Gauss-Kruger projection plane coordinate system as the basic coordinate space for aircraft navigation calculation. The central meridian of the projection plane coordinate system is determined according to the initial longitude in the initial latitude and longitude coordinates, and the initial latitude and longitude coordinates are converted into projection plane coordinates under the projection coordinate system. The data processing module (12) is used to convert the displacement vector of the aircraft in the carrier coordinate system into the geographic displacement vector in the geographic coordinate system based on the current heading angle of the aircraft, and to calculate the lateral distance, projection scale factor and meridian convergence angle of the aircraft to the central meridian at the current time according to the projection plane coordinates and current latitude of the aircraft at the current time. The coordinate positioning module (13) is used to construct a Jacobian compensation matrix based on the projection scale factor and the meridian convergence angle, and to perform incremental calculations on the geographic displacement vector according to the Jacobian compensation matrix in order to update the projection plane coordinates corresponding to the aircraft.

9. An electronic device, characterized in that, The device includes a processor (21), a memory (25), a user interface (23), and a network interface (24). The memory (25) is used to store instructions. The user interface (23) and the network interface (24) are used to communicate with other devices. The processor (21) is used to execute the instructions stored in the memory (25) to cause the electronic device (2) to perform the method as described in any one of claims 1-7.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1-7.

Images