Positioning method based on high-precision inertial navigation and digital orbit pose tight coupling fusion and application

Abstract

The invention discloses a positioning method and application based on high-precision inertial navigation and digital orbit pose tight coupling fusion, a high-precision inertial navigation and digital orbit pose tight coupling fusion positioning system is installed on a vehicle, and the high-precision inertial navigation and digital orbit pose tight coupling fusion positioning system comprises a high-precision inertial navigation unit, a digital orbit positioning unit and a self-adaptive data fusion unit. A magnetic nail and inertial navigation tight coupling position resolving scheme is innovatively adopted; a self-adaptive Kalman filtering algorithm is adopted, so that the problems caused by nonlinear characteristics of the system and inaccuracy of the model are effectively solved; the inertial navigation resolving technology is introduced, so that the positioning challenge in a tree-shaped turnout scene is effectively dealt with, and the technical defect that the detection of a magnetic nail system fails when the magnetic nail system passes through the turnout is successfully overcome; by means of the high-precision inertial navigation resolving capability, the arrangement distance of the magnetic nails is remarkably increased, so that the overall deployment cost of the system is effectively reduced, and the accuracy of digital orbit positioning and the reliability of an expansion function can be ensured.

Description

TECHNICAL FIELD

[0001] The application relates to a positioning method based on high-precision inertial navigation and multi-track pose tight coupling fusion. BACKGROUND

[0002] Digital rail rubber-tyred electric vehicle (DRT) is a new type of public transport tool developed based on modern tram technology. It uses electromagnetic markers, visual navigation and satellite navigation technology to realize digital track guidance, so that the vehicle can travel according to the predetermined route without physical track. The vehicle is equipped with inertial navigation, camera, millimeter wave radar, laser radar and various sensors to provide multiple ways for obtaining the attitude and environmental perception of the vehicle. Various electric actuators, such as driving motor, electronic steering system (EPS) and electronic brake system (EBS), provide technical convenience for the development of automatic driving.

[0003] Although the high-precision inertial navigation system has good autonomous positioning performance, the positioning error will gradually accumulate with the time drift. The multi-track positioning system can make up for this shortcoming. However, the current digital track uses magnetic nails as markers. In order to ensure the positioning accuracy, the magnetic nails are arranged at an interval of 1m along the track path. If the line is long, the installation cost will also increase accordingly. In addition, for large-scale stations, there are a large number of tree-shaped turnouts in the station. In order to avoid the interference between the magnetic nails, the magnetic nails are arranged on only one track within the detection range of the vehicle at the turnout, which has the risk of positioning loss or inaccuracy. In view of the above situation, the positioning method based on high-precision inertial navigation and multi-track pose tight coupling fusion is proposed to solve the above problems. SUMMARY

[0004] The purpose of the present application is to overcome the defects of the prior art and provide a positioning method based on high-precision inertial navigation and multi-track pose tight coupling fusion, which can guarantee the accuracy of multi-track positioning and the reliability of extended functions.

[0005] Another purpose of the present application is to provide an application of the positioning method based on high-precision inertial navigation and multi-track pose tight coupling fusion.

[0006] One of the technical solutions to achieve the above-mentioned purpose is: a positioning method based on high-precision inertial navigation and digital track pose tight coupling fusion, a high-precision inertial navigation and digital track pose tight coupling fusion positioning system is installed on the vehicle, the high-precision inertial navigation and digital track pose tight coupling fusion positioning system comprises a high-precision inertial navigation unit, a digital track positioning unit and an adaptive data fusion unit, the high-precision inertial navigation unit is used to obtain the attitude angle and position information of the vehicle; the digital track is a magnetic pin sequence buried in the ground, the digital track positioning unit calibrates the initial position of the vehicle according to the matching of the read magnetic pin information and the vehicle electronic map, and obtains the vehicle position information according to the calibrated magnetic pin spacing of the vehicle electronic map and the vehicle speed; the magnetic pin spacing is calibrated in the vehicle electronic map, and the speed calculated by the magnetic pin spacing and the magnetic pin reading time interval is used as the speed parameter of the high-precision inertial navigation unit; the magnetic pin sequence is a discrete quantity, and the speed output by the high-precision inertial navigation unit is used as the speed value required for the digital track calculation positioning between two magnetic pins; the adaptive data fusion unit fuses the attitude angle and position information measured by the high-precision inertial navigation unit and the vehicle position information obtained by the digital track positioning unit by using an adaptive Kalman filtering algorithm, to obtain the accurate positioning result of the vehicle.

[0007] The above-mentioned positioning method based on high-precision inertial navigation and digital track pose tight coupling fusion comprises the following steps:

[0008] S1, during the driving of the vehicle, the digital track positioning unit obtains the road information and the current position information of the current running line through the magnetic pin coding and the vehicle electronic map;

[0009] S2, taking the inertial navigation state at the moment of reading the magnetic pin as the initialization state, the high-precision inertial navigation unit calculates the acceleration component on the reference track through the attitude angle information and the accelerometer information, calculates the speed through the acceleration component and the sampling period, and transmits the speed value to the digital track positioning unit;

[0010] S3, the distance information between two magnetic pins is recorded in the vehicle electronic map, the digital track positioning unit calculates the speed component along the reference track direction through the two magnetic pin reading time interval and the distance information, and calibrates the output speed value of the high-precision inertial navigation unit with the speed component;

[0011] S4, the vehicle position information is provided by the digital track positioning unit, the longitudinal positioning is the magnetic pin number, and the lateral deviation is the magnetic pin deviation when the magnetic signal is detected; otherwise, the vehicle position information is calculated by combining the inertial navigation yaw angle measured by the high-precision inertial navigation unit with the vehicle electronic map information;

[0012] S5, the vehicle is equipped with two magnetic sensors, when the vehicle reads the magnetic pin signal, the attitude angle calculated by the two magnetic sensor deviations and the wheelbase is the initial value, and when a new magnetic pin signal is read, the attitude angle is calculated again to calibrate the attitude angle cumulative error of the high-precision inertial navigation unit;

[0013] S6, in the blank section between the two magnetic nails, the high-precision inertial navigation unit calculates the current vehicle attitude angle information through the inertial navigation yaw rate;

[0014] S7, in the data fusion processing of the adaptive data fusion unit, the track positioning unit calculates the running distance between the two magnetic nails according to the speed value output by the high-precision inertial navigation unit, and when the cumulative distance is greater than the distance of the next point recorded in the vehicle electronic map and the magnetic nail signal has not been detected, the cumulative distance is reset to zero and the index position of the vehicle electronic map is incremented, so as to ensure the accuracy of longitudinal positioning;

[0015] S8, in the data fusion processing of the adaptive data fusion unit, in the blank section between the two magnetic nails, the attitude angle when the previous magnetic nail is read is used as the initial value, the lateral deviation is calculated combined with the vehicle speed and the vehicle electronic map information, and the stable operation of the vehicle is maintained.

[0016] The application also provides an application of the above-mentioned positioning method based on high-precision inertial navigation and track pose tight coupling fusion in a passing siding scene.

[0017] The application of the above-mentioned positioning method based on high-precision inertial navigation and track pose tight coupling fusion in a passing siding scene, when the high-precision inertial navigation and track pose tight coupling fusion positioning system is initialized, the system receives the high-precision inertial navigation and magnetic sensor device signals on the vehicle, successfully enters the cycle listening event, and fails to terminate the process.

[0018] The system listens to the data sent by the inertial navigation and magnetic sensor, and reads the data when the data is updated;

[0019] The system starts a 4ms periodic timing task, and in the 4ms period, the current line position information is obtained according to the matching of the magnetic sensor data and the vehicle electronic map data, and the front and rear reference track data are extracted from the current position;

[0020] In the 4ms period, the speed is calculated according to the accelerometer data of the high-precision inertial navigation unit, so that when the magnetic sensor data is updated, the speed is calculated according to the vehicle speed and the distance between the two magnetic nails recorded in the vehicle electronic map, and if the speed calculated by the high-precision inertial navigation unit deviates greatly, the speed calculated by the track positioning unit is used for calibration, and the position is calculated;

[0021] In the 4ms period, the attitude angle when the magnetic nail is read by the magnetic sensor is used as the initial value of the attitude angle of the high-precision inertial navigation unit, and the attitude angle is calculated through the initial value of the attitude angle; the vehicle pose parameters are obtained through the attitude angle calculation and the position calculation, and the inertial navigation deviation is calculated combined with the reference track;

[0022] The system starts a 20ms periodic timing task, adds the calculation result of the inertial navigation deviation to the vehicle lateral control settlement module to calculate the steering instruction, writes the updated steering instruction into the DB, and controls the steering of the vehicle in the passing siding scene.

[0023] This invention also provides the application of the above-mentioned positioning method based on the tight coupling fusion of high-precision inertial navigation and digital orbital pose in scenarios with increased magnetic nail spacing.

[0024] The above-mentioned positioning method based on the tight coupling and fusion of high-precision inertial navigation and digital track pose is applied in scenarios with increased magnetic nail spacing. During vehicle operation, the digital track positioning unit obtains road information and current location information of the current route through magnetic nail encoding and on-board electronic map.

[0025] The vehicle is equipped with two magnetic sensors. When the vehicle reads the magnetic nail signal, the attitude angle calculated by the deviation of the two magnetic sensors and the wheelbase is used as the initial value. When a new magnetic nail signal is read, the attitude angle is recalculated to calibrate the cumulative attitude angle error of the high-precision inertial navigation unit.

[0026] In the blank area between the two magnetic nails and the magnetic sensor, the high-precision inertial navigation unit calculates the current vehicle attitude angle information through the inertial navigation yaw rate.

[0027] In the data fusion processing of the adaptive data fusion unit, in the blank area between the two magnetic nails, the attitude angle when the magnetic nail was read was used as the initial value, and the lateral deviation was calculated by combining the vehicle electronic map information and vehicle speed to maintain stable vehicle operation.

[0028] This invention presents a positioning method based on the tight coupling and fusion of high-precision inertial navigation (INS) and multi-track positioning. While high-precision INS systems possess excellent autonomous positioning performance, their positioning errors accumulate over time. Multi-track positioning methods, on the other hand, offer advantages such as non-contact operation and high accuracy, and can overcome this drawback. To improve the stability and accuracy of vehicle pose measurement, based on research into INS and visual positioning, and combining the advantages of both, a fusion positioning method based on the tight coupling of high-precision INS and multi-track positioning is proposed to achieve information fusion and ensure accurate vehicle positioning. However, fusion positioning suffers from significant errors in individual data. Conventional Kalman filtering introduces substantial errors into the innovation as the observation error increases, leading to divergence in the filtering results. The improved adaptive Kalman filtering introduces innovation error tracking, compares the difference between measured and predicted values ​​to estimate the errors in the system, and corrects these errors accordingly.

[0029] The positioning method and application based on the tight coupling fusion of high-precision inertial navigation and digital orbit pose of the present invention have the following technical effects:

[0030] (1) innovatively adopts a position solution scheme of tightly coupling magnetic nails and inertial navigation;

[0031] (2) an adaptive Kalman filtering algorithm is adopted, and problems caused by nonlinear characteristics of the system and model inaccuracy are effectively solved;

[0032] (3) by introducing an inertial navigation solution technology, the positioning challenge in a tree turnout scene is effectively solved, and the technical short board of the magnetic nail system in the detection failure when passing through a turnout is successfully made up;

[0033] (4) with the help of high-precision inertial navigation solution capability, the magnetic nail layout distance is significantly increased, so that the overall deployment cost of the system is effectively reduced. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a schematic diagram of the positioning method based on the high-precision inertial navigation and the tightly coupled fusion of the number rail pose of the application;

[0035] Figure 2 is a schematic diagram of the adaptive Kalman filtering;

[0036] Figure 3 is a flowchart of the positioning method of the application when applied in a turnout passing scene;

[0037] Figure 4 is an Ackerman steering model diagram in a magnetic nail distance increasing scene;

[0038] Figure 5 is an inertial navigation prediction simulation diagram of the positioning method of the application when applied in a magnetic nail distance increasing scene. DETAILED DESCRIPTION

[0039] In order for those skilled in the art to better understand the technical solutions of the present application, the specific embodiments thereof will be described in detail below with reference to the accompanying drawings:

[0040] Please refer to Figure 1 and Figure 2The embodiment of the application discloses a positioning method based on high-precision inertial navigation and digital track pose tight coupling fusion, a positioning method based on high-precision inertial navigation and digital track pose tight coupling fusion, and a high-precision inertial navigation and digital track pose tight coupling fusion positioning system installed on a vehicle. The high-precision inertial navigation and digital track pose tight coupling fusion positioning system comprises a high-precision inertial navigation unit 1, a digital track positioning unit 2 and an adaptive data fusion unit 3. The high-precision inertial navigation unit 1 is used for acquiring attitude angle and position information of the vehicle. The digital track is a magnetic pin sequence buried in the ground. The digital track positioning unit 2 calibrates the initial position of the vehicle according to the matching of the read magnetic pin information and the vehicle-mounted electronic map, and obtains the position information of the vehicle according to the calibrated magnetic pin spacing of the vehicle-mounted electronic map and the vehicle speed. The magnetic pin spacing is calibrated in the vehicle-mounted electronic map. The digital track positioning unit 2 takes the speed calculated by the magnetic pin spacing and the magnetic pin reading time interval as the speed parameter of the high-precision inertial navigation unit. The magnetic pin sequence is a discrete quantity. The high-precision inertial navigation unit 1 outputs the speed as the speed value required for the digital track calculation positioning between two magnetic pins. The adaptive data fusion unit 3 fuses the attitude angle and position information (pose information) measured by the high-precision inertial navigation unit and the position information of the vehicle acquired by the digital track positioning unit by using an adaptive Kalman filtering algorithm, so as to obtain the accurate positioning result of the vehicle.

[0041] The positioning method based on high-precision inertial navigation and digital track pose tight coupling fusion comprises the following steps:

[0042] S1, in the process of vehicle driving, the digital track positioning unit 2 acquires the road information and the current position information of the current running line through the magnetic pin coding and the vehicle-mounted electronic map;

[0043] S2, taking the inertial navigation state at the moment of reading the magnetic pin as the initialization state, the high-precision inertial navigation unit 1 calculates the acceleration component on the reference track through the attitude angle information and the accelerometer information, calculates the speed through the acceleration component and the sampling period, and transmits the speed value to the digital track positioning unit;

[0044] S3, the vehicle-mounted electronic map records the distance information between two magnetic pins. The digital track positioning unit 2 calculates the speed component in the direction of the reference track through the two magnetic pin reading time intervals and the distance information, and calibrates the output speed value of the high-precision inertial navigation unit 1 by using the speed component;

[0045] S4, the digital track positioning unit 2 provides the vehicle position information. The longitudinal positioning is the magnetic pin number, and the transverse deviation is the magnetic pin deviation when the magnetic signal is detected. Otherwise, the vehicle position information is calculated by combining the inertial navigation yaw angle measured by the high-precision inertial navigation unit 1 and the vehicle-mounted electronic map information;

[0046] S5, the vehicle is equipped with two magnetic sensors. When the vehicle reads the magnetic nail signal, the attitude angle calculated by the digital track positioning unit through the deviation of the two magnetic sensors and the wheelbase is the initial value. When a new magnetic nail signal is read, the attitude angle is recalculated to calibrate the cumulative error of the attitude angle of the high-precision inertial navigation unit 1.

[0047] S6, in the blank area of ​​the magnetic sensor between the two magnetic nails, the high-precision inertial navigation unit 1 calculates the current vehicle attitude angle information through the inertial navigation yaw rate;

[0048] S7, in the data fusion processing of the adaptive data fusion unit 3, the track positioning unit 1 calculates the driving distance between the two magnetic nails based on the speed value output by the high-precision inertial navigation unit. If the cumulative distance is greater than the distance to the next point recorded in the vehicle electronic map and no magnetic nail signal is detected, the cumulative distance is set to zero and incremented at the index position of the vehicle electronic map to ensure the accuracy of longitudinal positioning.

[0049] S8, in the data fusion processing of the adaptive data fusion unit 3, in the blank section between the two magnetic nails, the attitude angle when the magnetic nail was read was used as the initial value, and the lateral deviation was calculated by combining the vehicle electronic map information and vehicle speed to maintain stable vehicle operation.

[0050] Please see Figure 2 While high-precision inertial navigation systems (INS) possess excellent autonomous positioning performance, their positioning errors accumulate over time. Digital orbit positioning (DOR) methods, however, offer advantages such as non-contact operation and high accuracy, thus mitigating this drawback. To improve the stability and accuracy of vehicle pose measurement, this paper proposes a positioning method based on the tight coupling and fusion of high-precision INS and DOR data, building upon research in INS and visual positioning. This fusion ensures precise vehicle positioning. However, the fused positioning suffers from significant errors in individual data points. Conventional Kalman filtering introduces substantial errors into the innovation as the observation error increases, leading to divergence in the filtering results. The improved adaptive filtering introduces innovation error tracking, comparing the differences between measured and predicted values ​​to estimate system errors and making corrections accordingly.

[0051] Please see Figure 3 This invention relates to the application of a positioning method based on the tight coupling fusion of high-precision inertial navigation and digital track pose in a turnout scenario. In this scenario, vehicle positioning is achieved through the complete steps of the positioning method based on the tight coupling fusion of high-precision inertial navigation and digital track pose according to this invention.

[0052] In the design of the turnout scene, considering that the magnetic sensor can only identify one strong magnetic field within its detection range, only one magnetic pin is arranged on the magnetic pin road in the magnetic sensor detection range of the turnout. Different tracks are realized by adding offsets in the electronic map. Therefore, in the actual running scene, the vehicle cannot completely follow the reference track, and once it deviates greatly at the critical point of the magnetic sensor detection range, it will read two magnetic pins and choose the one with stronger field strength, causing the vehicle to deviate from the wrong track and derail. Therefore, a tightly coupled fusion positioning method of inertial navigation and digital track is designed, which compensates for the deficiency by solving the inertial navigation and auxiliary magnetic processing when passing through the turnout.

[0053] The yaw parameter measured by the high-precision inertial navigation / gyroscope on the vehicle is taken as the input, the output position and attitude information is converted from the inertial coordinate system to the road coordinate system, and the lateral deviation detection function of the discrete magnetic pin is fused to design a vehicle pose prediction algorithm.

[0054] When the high-precision inertial navigation and digital track pose tightly coupled fusion positioning system (hereinafter referred to as "system") is initialized, the system accepts the high-precision inertial navigation and magnetic sensor device signals on the vehicle, successfully enters the loop listening event, and fails to terminate the process;

[0055] The system listens to the data sent by the inertial navigation and magnetic sensor, and reads the data when the data is updated;

[0056] The system starts a 4ms periodic timing task, and in the 4ms period, the current line position information is obtained by matching the magnetic sensor data with the vehicle electronic map data, and the front and rear reference track data is extracted from the current position;

[0057] In the 4ms period, the accelerometer data of the high-precision inertial navigation unit is used to calculate the speed, so that when the magnetic sensor data is updated, the speed is calculated based on the vehicle speed and the distance between the two magnetic pins recorded in the vehicle electronic map. If the speed calculated by the high-precision inertial navigation unit deviates greatly, the speed calculated by the digital track positioning unit is used for calibration, and the position is calculated;

[0058] In the 4ms period, the attitude angle of the magnetic pin read by the magnetic sensor is taken as the initial value of the attitude angle of the high-precision inertial navigation unit, and the attitude angle is calculated through the initial value of the attitude angle. The vehicle pose parameters are obtained through attitude angle calculation and position calculation, and the inertial navigation deviation is calculated combined with the reference track;

[0059] The system starts a 20ms periodic timing task, adds the calculation result of the inertial navigation deviation to the vehicle lateral control settlement module to calculate the steering command, and writes the updated steering command into the DB to control the steering of the vehicle in the turnout scene.

[0060] Please refer to Figure 4 and Figure 5The application of the positioning method based on high-precision inertial navigation and tightly coupled fusion of track pose in the scenario of increased magnetic nail spacing.

[0061] To ensure the accuracy and reliability of automatic driving control, the track nails are designed to be arranged at an interval of 1 m, and the vehicle deviation information is read by the magnetic sensor, if the magnetic nail spacing is increased, there is a possibility of accidents caused by the inability to obtain the vehicle deviation information in time at low speed; the longer the track line, the higher the construction cost, therefore, in the application of the positioning method based on high-precision inertial navigation and tightly coupled fusion of track pose in the magnetic nail spacing increased scenario, the pose information of the inertial navigation unit can accurately obtain the offset between the two magnetic nails and ensure the accuracy and safety of the control.

[0062] In the scenario of increased magnetic nail spacing, the positioning of the vehicle is realized through the steps S1, S5, S6 and S8 in the positioning method based on high-precision inertial navigation and tightly coupled fusion of track pose.

[0063] During the driving of the vehicle, the track positioning unit obtains the road information and the current position information of the current running line through the magnetic nail coding and the vehicle-mounted electronic map;

[0064] The vehicle is equipped with two magnetic sensors, when the vehicle reads the magnetic nail signal, the attitude angle calculated by the two magnetic sensor deviations and the wheelbase is the initial value, and when a new magnetic nail signal is read, the attitude angle is calculated again to calibrate the attitude angle cumulative error of the high-precision inertial navigation unit;

[0065] In the blank section of the two magnetic nails, the high-precision inertial navigation unit calculates the current vehicle attitude angle information through the inertial navigation yaw angle rate;

[0066] In the data fusion processing of the adaptive data fusion unit, in the blank section between the two magnetic nails, the attitude angle when the previous magnetic nail is read is used as the initial value, the lateral deviation is calculated combined with the vehicle-mounted electronic map information and the vehicle speed, and the stable operation of the vehicle is maintained.

[0067] For the inertial navigation positioning prediction, the vehicle kinematics model needs to be combined. The high-precision inertial navigation and tightly coupled fusion positioning system in the application simplifies the intelligent vehicle into a bicycle model based on the vehicle Ackerman turning principle, takes the center of the front axle of the vehicle as the tangent point and the longitudinal body of the vehicle as the tangent line, and controls the front wheel deflection angle, so that the vehicle can drive along the (track) preview point.

[0068] According to the Ackerman steering model, we have:

[0069] tan (delta) = L / R (1)

[0070] psi' / v = 1 / R = K (2)

[0071] In formula (1) and formula (2), L is a vehicle wheelbase; R is a turning radius; delta is a front wheel steering angle; v is a vehicle speed; and psi is a vehicle yaw angle (body direction angle).

[0072] Bias1 prediction model:

[0073]

[0074] theta = v*dt*curv (4)

[0075] In formula (3) and formula (4), bias1 is a 1-axis deviation prediction; v is a vehicle speed; psi is a vehicle yaw angle (body direction angle); curv is a map curvature; theta is an offset angle based on a reference path; and dt is a system sampling period.

[0076] Referring back to Figure 5 According to a demagnetization fault diagram (demagnetization point mark), it can be known that the Bias1 prediction (1-axis deviation prediction) is consistent with the actual deviation, and the consistency degree is higher than 93%, so theoretically, the positioning and calculation using inertial navigation can maintain the positioning in the case of magnetic nail failure, and the fusion positioning of the magnetic nail and the IMU is realized through the initial value supplementing and prediction reasoning, and the magnetic nail lateral deviation can be replaced in a short time.

[0077] In summary, the positioning method and application based on the high-precision inertial navigation and the tightly coupled fusion of the number track pose of the application innovatively adopt a magnetic nail and inertial navigation tightly coupled position solution scheme; an adaptive Kalman filtering algorithm is adopted, and the problems caused by the non-linear characteristics of the system and the model inaccuracy are effectively solved; the inertial navigation solution technology is introduced, the positioning challenge in the tree-shaped turnout scene is effectively solved, the technical short board that the magnetic nail system fails to detect when passing through the turnout is successfully made up; with the aid of the high-precision inertial navigation solution capability, the magnetic nail layout distance is significantly increased, so that the overall deployment cost of the system is effectively reduced.

[0078] Those skilled in the art of the present technology should recognize that the above embodiments are only used to illustrate the present application, and are not used as a limitation on the present application, and as long as the changes and modifications of the above described embodiments are within the scope of the spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A positioning method based on high-precision inertial navigation and number rail pose tight coupling fusion, characterized in that, The vehicle is provided with a high-precision inertial navigation and digital track pose tightly coupled fusion positioning system, which comprises a high-precision inertial navigation unit, a digital track positioning unit and an adaptive data fusion unit. The high-precision inertial navigation unit is used to obtain the attitude angle and position information of the vehicle. The digital track is a magnetic pin sequence buried in the ground. The digital track positioning unit calibrates the initial position of the vehicle according to the matching of the read magnetic pin information and the vehicle electronic map, and obtains the vehicle position information according to the calibrated magnetic pin spacing of the vehicle electronic map and the vehicle speed. The magnetic pin spacing is calibrated in the vehicle electronic map. The digital track positioning unit takes the speed calculated by the magnetic pin spacing and the magnetic pin reading time interval as the speed parameter of the high-precision inertial navigation unit. The magnetic pin sequence is a discrete quantity. The speed output by the high-precision inertial navigation unit is taken as the speed value required for the digital track calculation positioning between two magnetic pins. The adaptive data fusion unit adopts an adaptive Kalman filtering algorithm to fuse the attitude angle and position information measured by the high-precision inertial navigation unit and the vehicle position information obtained by the digital track positioning unit, so as to obtain the accurate positioning result of the vehicle.

2. The positioning method based on high-precision inertial navigation and tightly coupled fusion of numerical rail pose according to claim 1, characterized in that, The method comprises the following steps: S1. During the driving of the vehicle, the digital track positioning unit obtains the road information and the current position information of the current running line through the magnetic pin coding and the vehicle electronic map; S2. Taking the inertial navigation state at the moment of reading the magnetic pin as the initialization state, the high-precision inertial navigation unit calculates the acceleration component on the reference track through the attitude angle information and the accelerometer information, calculates the speed through the acceleration component and the sampling period, and transmits the speed value to the digital track positioning unit; S3. The vehicle electronic map records the distance information between two magnetic pins. The digital track positioning unit calculates the speed component in the direction of the reference track through the distance information and the time interval between the reading of two magnetic pins, and calibrates the output speed value of the high-precision inertial navigation unit with the speed component; S4. The vehicle position information is provided by the digital track positioning unit. The longitudinal positioning is the magnetic pin number, and the lateral deviation is the magnetic pin deviation when the magnetic signal is detected. Otherwise, the vehicle position information is calculated by the inertial navigation yaw angle measured by the high-precision inertial navigation unit and the vehicle electronic map information; S5. The vehicle is provided with two magnetic sensors. When the vehicle reads the magnetic pin signal, the attitude angle calculated by the two magnetic sensor deviations and the wheelbase is the initial value. When a new magnetic pin signal is read, the attitude angle is calculated again to calibrate the accumulated error of the attitude angle of the high-precision inertial navigation unit; S6. In the blank section between two magnetic pins, the high-precision inertial navigation unit calculates the current vehicle attitude angle information through the inertial navigation yaw angle rate; S7. In the data fusion processing of the adaptive data fusion unit, the digital track positioning unit calculates the driving distance between two magnetic pins according to the speed value output by the high-precision inertial navigation unit. If the accumulated distance is greater than the distance to the next point recorded in the vehicle electronic map and the magnetic pin signal has not been detected, the accumulated distance is reset to zero and the index position in the vehicle electronic map is incremented, so as to ensure the accuracy of the longitudinal positioning; S8. In the data fusion processing of the adaptive data fusion unit, in the blank section between two magnetic pins, the attitude angle at the previous reading of the magnetic pin is taken as the initial value, the lateral deviation is calculated by combining the vehicle electronic map information and the vehicle speed, and the stable operation of the vehicle is maintained.

3. The application of a positioning method based on tight coupling of high-precision inertial navigation and numerical rail pose in a turnout scene according to claim 1 or 2.

4. The application of a positioning method based on high-precision inertial navigation and tightly coupled fusion of numerical rail pose in the overpass turnout scene according to claim 3, characterized in that, When the high-precision inertial navigation and numerical rail pose tight coupling fusion positioning system is initialized, the system accepts high-precision inertial navigation and magnetic sensor device signals on the vehicle, successfully enters the loop listening event, and terminates the process if it fails; The system listens to the data sent by the inertial navigation and magnetic sensor, and reads in the data when the data is updated; The system starts a 4ms periodic timing task, and within the 4ms period, it obtains the current line position information based on the matching of magnetic sensor data and vehicle electronic map data, and extracts the front and rear reference trajectory data from the current position; Within the 4ms period, the accelerometer data of the high-precision inertial navigation unit is used to calculate the speed, so that when the magnetic sensor data is updated, the speed is calculated based on the vehicle speed and the distance between the two magnetic spikes recorded in the vehicle electronic map, and if the speed calculated by the high-precision inertial navigation unit deviates significantly, the speed calculated by the numerical rail positioning unit is used for calibration, and the position is calculated; Within the 4ms period, the attitude angle of the magnetic sensor when reading the magnetic spike is used as the initial value of the attitude angle of the high-precision inertial navigation unit, and the attitude angle is calculated through this initial value; the vehicle pose parameters are obtained through attitude angle calculation and position calculation, and the inertial navigation deviation is calculated in combination with the reference trajectory; The system starts a 20ms periodic timing task, adds the calculation result of the inertial navigation deviation to the vehicle lateral control settlement module to calculate the steering command, and writes the updated steering command into the DB to control the vehicle steering in the turnout scene.

5. The application of a positioning method based on tight coupling of high-precision inertial navigation and numerical rail pose in a magnetic spike distance increase scene according to claim 1 or 2.

6. The application of a positioning method based on high-precision inertial navigation and tightly coupled fusion of numerical rail pose in the scenario of increased magnetic nail spacing, according to claim 5, characterized in that, During vehicle travel, the numerical rail positioning unit obtains the road information and current position information of the current running line through magnetic spike coding and vehicle electronic map; The vehicle is equipped with two magnetic sensors, and when the vehicle reads the magnetic spike signal, the attitude angle calculated by the deviation of the two magnetic sensors and the wheelbase is used as the initial value, and when a new magnetic spike signal is read, the attitude angle is recalculated to correct the cumulative error of the attitude angle of the high-precision inertial navigation unit; In the blank section between two magnetic spikes, the high-precision inertial navigation unit calculates the current vehicle attitude angle information through the inertial navigation yaw angle rate; In the data fusion processing of the adaptive data fusion unit, in the blank section between two magnetic spikes, the attitude angle at the previous reading of the magnetic spike is used as the initial value, the vehicle electronic map information and vehicle speed are combined to calculate the lateral deviation, and the vehicle is maintained in stable operation.

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