Unmanned aerial vehicle thrust line measuring device and measuring method based on inertial measurement unit

Abstract

The application provides a kind of unmanned aerial vehicle thrust line measuring device and measuring method based on inertial measurement unit, comprising: measuring cylinder installation connecting seat, it includes circular bottom plate and annular side wall, also includes tubular connecting piece, connecting piece includes first section and second section connected with each other, circular bottom plate is opened through hole, tubular connecting piece is fixed at through hole;PCB circuit board is installed in connecting seat, processor, IMU array and external communication interface are arranged on PCB circuit board, IMU array is used to collect the attitude angle of measuring cylinder, processor is used to data analysis processing, and is exported through external communication interface;Upper cover is fixedly installed on connecting seat;Measuring cylinder and boom, the top of measuring cylinder is fixed with the second section of connecting piece, the bottom is fixed on unmanned aerial vehicle, boom is successively penetrated measuring cylinder, connecting piece and upper cover, and the bottom is suspended unmanned aerial vehicle.The application realizes the automation of measuring process, and the measuring data can be traced back, improves the measuring efficiency and measuring accuracy.

Description

Technical Field

[0001] The present invention relates to the field of aviation technology, and in particular to a thrust line measuring device and a measuring method for an unmanned aerial vehicle (UAV) based on an inertial measurement unit (IMU). Background Art

[0002] Rocket-assisted launch is a crucial step in drone flight. A drone relies on its own power and the thrust generated by its rocket boosters to accelerate from a stationary state to a safe flight speed and altitude. After the rocket boosters separate, the drone enters its flight path under its own power. The speed of a drone during takeoff is determined by the thrust of the booster rocket and engine, while its stability during takeoff is determined by the aircraft's pitch angle. Accurate thrust line measurement is crucial for a successful drone launch.

[0003] At present, the thrust line of a rocket-assisted zero-length launch drone is basically measured by hanging. The drone is hung by a boom, and the thrust line of the drone is measured and adjusted by measuring the azimuth distance between the boom and the measuring tube. For example, the thrust line measuring device of the prior art (CN111196375A) includes a hanging ring, a base assembly, a first adjustment assembly, a second adjustment assembly, and a measuring assembly. The rocket cone and the measuring tube constitute the use environment of the boom body. However, the observation of the thrust line data in this technology requires the operator to stand on the operating table for manual reading, which has problems such as cumbersome operation, large measurement error, and long measurement time, and the automation of data reading and processing is not achieved.

[0004] In addition, the current measurement process is mainly carried out manually using measuring tools such as steel rulers and calipers (such as the existing technologies CN209617539U and CN210375528U). When faced with problems such as body shaking in the actual measurement environment and the measurement position being unsuitable for human operation, there are problems such as large measurement errors, long measurement time, and difficult operation, which can easily lead to inaccurate measurement results and cause drone launch failure. Summary of the Invention

[0005] In view of this, an embodiment of the present application provides a UAV thrust line measurement system based on a planar inertial measurement unit array to achieve the purposes of automating the measurement process, traceable measurement data, no human intervention, and improving measurement efficiency and measurement accuracy.

[0006] The present application provides the following technical solution: a UAV thrust line measurement device based on an inertial measurement unit, comprising:

[0007] A measuring cylinder mounting and connecting seat, comprising a circular base plate and an annular side wall fixed to the circular base plate, so that the measuring cylinder mounting and connecting seat is disc-shaped as a whole, and further comprising a tubular connecting member, the tubular connecting member comprising a first section and a second section connected to each other, wherein the diameter of the first section is smaller than the diameter of the second section, a through hole is provided on the circular base plate, the tubular connecting member is fixed at the through hole, and the first section is located within the disc of the measuring cylinder mounting and connecting seat, so that an annular groove is formed within the measuring cylinder mounting and connecting seat, and the second section is located outside the disc of the measuring cylinder mounting and connecting seat;

[0008] A PCB circuit board, the PCB circuit board is fixedly mounted in the annular groove of the measuring cylinder mounting connector, the PCB circuit board is provided with a processor, an IMU array, and an external communication interface, the IMU array is used to collect the attitude angle of the measuring cylinder, the processor is used to analyze and process the attitude angle data collected by the IMU array, and send the data to an external device through the external communication interface;

[0009] A connecting seat upper cover, wherein a through hole is provided in the middle of the connecting seat upper cover, and the connecting seat upper cover is fixedly mounted on the measuring cylinder mounting connecting seat;

[0010] The measuring cylinder and the suspension rod are fixedly connected to the top of the measuring cylinder and the second section of the tubular connector, and the bottom end of the measuring cylinder is fixed on the drone. The suspension rod passes through the measuring cylinder, the tubular connector and the upper cover of the connecting seat in sequence, and the drone is suspended at the bottom end of the suspension rod.

[0011] According to one embodiment of the present application, the IMU array consists of four pieces, and the four IMU chips are soldered on the PCB circuit board in a circular orthogonal arrangement.

[0012] According to one embodiment of the present application, the device also includes a 4.2V parallel lithium battery pack, and the PCB circuit board also includes a lithium battery power supply and charging interface and an LDO regulator. The 4.2V parallel lithium battery pack powers the entire system through the lithium battery power supply and charging interface and the LDO regulator.

[0013] According to one embodiment of the present application, a charging hole is provided on the annular side wall of the measuring cylinder mounting connector for charging the 4.2V parallel lithium battery pack.

[0014] According to one embodiment of the present application, the PCB circuit board also includes a burning and debugging interface, a switch button, a lithium battery charging management chip, a Type-C charging port, a charging status indicator light, and a working status indicator light.

[0015] According to an embodiment of the present application, the connection seat upper cover is fixedly mounted on the measuring cylinder mounting connection seat by screws, and the PCB circuit board is fixedly mounted in the annular groove of the measuring cylinder mounting connection seat by screws.

[0016] According to one embodiment of the present application, the processor is STM32F103C8T6 in LQFP48 package.

[0017] The present application also provides a measurement method for the UAV thrust line measurement device based on an inertial measurement unit as described above, comprising:

[0018] After the system is powered on, the processor communicates with the four IMU arrays through the SPI interface to collect the raw data of the IMU arrays;

[0019] Calculate the zero bias and scale coefficient of the IMU array based on the static data of the IMU array;

[0020] Writing the zero bias and scale factor of the IMU array into the processor, so as to correct the offline error of the raw data of the IMU array through the processor;

[0021] Based on the corrected raw data of the IMU array, the spectral density of the angle random walk and the rate random walk of each IMU itself and the spectral density correlation of the angle random walk and the rate random walk between the IMUs are calculated using the Allan variance algorithm. Then, based on the spectral density correlation, the optimal linear combination weight of the IMU array gyroscope signal is calculated using the optimal linear weight estimation algorithm. The optimal linear combination weight is written into the processor so that the processor performs weighted fusion on the data of the IMU array to obtain fused attitude data. Finally, the fused attitude data is converted into thrust line measurement values ​​and output.

[0022] Existing UAV thrust line measurement devices all rely on mechanical measuring instruments and manual readings based on the hanging method, which lacks accuracy and efficiency in data reading. Compared with the existing technology, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0023] The embodiment of the present invention proposes a UAV thrust line measurement system solution based on a planar inertial measurement unit array, including a measuring tube mounting connector, an inertial measurement unit array circuit board, an upper cover, etc. The embodiment of the present invention utilizes four annular orthogonally mounted IMU arrays to obtain the attitude angle of the measuring tube through offline calibration and weighted fusion, and then uses known parameters to convert the deviation value of the center of gravity and thrust line of the UAV, and sends the data to the upper computer for processing and storage. The measurement process of the embodiment of the present invention does not require human intervention, avoids direct contact between personnel and measuring equipment such as steel rulers and calipers and the measuring tube and cables or booms, reduces interference with the measurement process, and can automatically collect data and calculate the deviation value of the center of gravity and thrust line of the UAV, thereby improving the efficiency and accuracy of the measurement and effectively ensuring the rocket-assisted zero-length launch of the UAV. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0025] Figure 1 This is a schematic structural assembly diagram of an embodiment of a UAV thrust line measurement system based on a planar inertial measurement unit array according to the present invention;

[0026] Figure 2 This is a schematic diagram of the use of an embodiment of the present invention in a hanging method application;

[0027] Figure 3a This is a schematic structural diagram of a measuring cylinder mounting connector according to an embodiment of the present invention;

[0028] Figure 3b This is another structural schematic diagram of the measuring cylinder mounting connector according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the installation of major components on the front side of a PCB circuit board according to an embodiment of the present invention;

[0030] Figure 5 This is a schematic diagram of the installation of major components on the reverse side of a PCB circuit board according to an embodiment of the present invention;

[0031] Figure 6a This is a schematic structural diagram of the upper cover of the measuring cylinder mounting connector according to an embodiment of the present invention;

[0032] Figure 6b This is another structural schematic diagram of the upper cover of the measuring cylinder mounting connector according to an embodiment of the present invention;

[0033] Figure 7 is a schematic diagram of the processor of the present invention;

[0034] Figure 8 It is a flow chart of an embodiment of a UAV thrust line measurement system based on a planar inertial measurement unit of the present invention;

[0035] Among them, 1. Measuring tube mounting connector; 2. PCB circuit board; 3. 4.2V parallel lithium battery pack; 4. Connector cover; 5. Measuring tube; 101. First mounting screw hole; 102. Second mounting screw hole; 103. Tightening screw hole; 104. Charging port; 201. Processor chip; 202. IMU array; 203. External communication interface (can be connected to wireless communication module and computer communication); 204. Burning and debugging interface; 205. Lithium battery power supply and charging interface; 206. Switch button; 207. Lithium battery charging management chip; 208. Type-C charging port; 209. Charging status indicator; 210. Working status indicator; 211. LDO voltage regulator; 212. PCB mounting hole; 401. Top cover mounting hole; 402. Charging status indicator hole; 403. Key switch hole; 404. Working status indicator hole. DETAILED DESCRIPTION

[0036] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0037] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0038] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0039] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0040] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples. However, one skilled in the art will appreciate that the aspects described can be practiced without these specific details.

[0041] The following describes the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0042] The existing technologies all use the hanging method to measure the thrust line of the drone, and directly measure the difference between the center of gravity of the drone and the thrust line through external measuring instruments and equipment. Since the cable or boom always passes through the center of gravity of the drone and is plumb to the ground during the hanging process, the measurement of the difference between the center of gravity of the drone and the thrust line can also be indirectly obtained by measuring and converting the attitude of the measuring barrel. The measurement of the attitude angle of the measuring barrel can be obtained by an inertial measurement unit (IMU) sensor. Therefore, the present invention provides a drone thrust line measurement solution based on a planar inertial measurement unit array, specifically involving an IMU system design and data processing method installed with four annular orthogonal arrays. It is suitable for the field of rapid and automatic measurement of drone thrust lines.

[0043] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a UAV thrust line measurement device based on an inertial measurement unit, comprising:

[0044] A measuring cylinder mounting and connecting seat 1, comprising a circular base plate and an annular side wall fixed to the circular base plate, so that the measuring cylinder mounting and connecting seat 1 is disc-shaped as a whole, and further comprising a tubular connector, the tubular connector comprising a first section and a second section connected to each other, wherein the diameter of the first section is smaller than the diameter of the second section, a through hole is provided on the circular base plate, the tubular connector is fixed at the through hole, and the first section is located within the disc of the measuring cylinder mounting and connecting seat 1, so that an annular groove is formed in the measuring cylinder mounting and connecting seat 1, and the second section is located outside the disc of the measuring cylinder mounting and connecting seat 1;

[0045] A PCB circuit board 2, the PCB circuit board 2 being fixedly mounted in the annular groove of the measuring cylinder mounting connector 1, the PCB circuit board 2 being provided with a processor, an IMU array 202, and an external communication interface 203. The IMU array 202 is used to collect the attitude angle of the measuring cylinder 5, and the processor is used to analyze and process the attitude angle data collected by the IMU array 202, and transmit the data to an external device via the external communication interface;

[0046] A connecting seat upper cover 4, wherein a through hole is provided in the middle of the connecting seat upper cover 4, and the connecting seat upper cover 4 is fixedly mounted on the measuring cylinder mounting connecting seat 1;

[0047] The measuring tube 5 and the boom are fixedly connected to each other at the top end of the measuring tube 5 and the second section of the tubular connector. The bottom end of the measuring tube 5 is fixed on the drone. The boom passes through the measuring tube 5, the tubular connector and the upper cover 4 of the connecting seat in sequence. The drone is suspended at the bottom end of the boom.

[0048] In some embodiments of the present invention, Figure 3a and 3bAs shown, the connector cover 4 is fixedly mounted on the opening of the measuring cylinder mounting connector 1, so that the measuring cylinder 5 mounting connector 1 and the connector cover 4 together form a housing structure that accommodates the PCB 2. Several first mounting screw holes 101 are evenly spaced and extend outward from the edge of the measuring cylinder mounting connector 1. Corresponding cover mounting holes 401 are provided on the connector cover 4, allowing the connector cover 4 and the measuring cylinder mounting connector 1 to be screwed together via these first and cover mounting holes 101. The PCB 2 is fixedly mounted within the annular groove of the measuring cylinder mounting connector 1. Several second mounting screw holes 102 are evenly spaced on the inner side of the annular sidewall of the measuring cylinder mounting connector 1. Several PCB mounting holes 212 are provided on the PCB 2, corresponding in position to the PCB mounting holes 212 for screw securement. The second section of the tubular connector is secured to the measuring cylinder 5 via set screw holes 103.

[0049] In some embodiments of the present invention, a PCB circuit board 2 is provided, and the PCB circuit board 2 is made of a four-layer board. Figure 4 and Figure 5 As shown, the PCB circuit board 2 mainly consists of a processor 201, four IMU arrays 202, an external communication interface 203, a burning and debugging interface 204, a lithium battery power supply and charging interface 205, a switch button 206, a lithium battery charging management chip 207, a Type-C charging port 208, a charging status indicator 209, an operating status indicator 210, and an LDO regulator 211. These components and their accessories are mounted on the PCB circuit board 2 by welding. The four IMU chips of the IMU array 202 are welded on the PCB circuit board 2 in a circular orthogonal arrangement.

[0050] The processor 201 is the main control unit of the entire system, which is used to analyze and process the data collected by the IMU array 202 and send the data to the computer through the external communication interface 203 for storage and further processing. Figure 1 、 Figure 4 and Figure 5 As shown, the device also includes a 4.2V parallel lithium battery pack 3, which powers the entire system through a lithium battery power supply and charging interface 205 and an LDO regulator 211, and a working status indicator 210 displays the power supply status of the system; when charging, the external world plugs a universal USB to Type-C power cable into the Type-C charging port 208, and charges the 4.2V parallel lithium battery pack 3 through the lithium battery charging management chip 207, and the charging status indicator 209 displays the current charging status of the lithium battery.

[0051] In some embodiments of the present invention, a charging hole 104 is provided on the annular side wall of the measuring cylinder mounting connector 1 for charging the 4.2V parallel lithium battery pack 3 .

[0052] like Figure 6a and Figure 6b As shown, the staff can operate the button switch 206 through the button switch hole 403 opened on the connection seat cover 4; observe the working status indicator light 210 through the working status indicator hole 404 opened on the connection seat cover 4; and observe the charging status indicator light 209 through the charging status indicator hole 402 opened on the connection seat cover 4.

[0053] In some embodiments of the present invention, Figure 7 As shown, the processor in this embodiment of the present invention uses an STM32F103C8T6 processor chip 201 in an LQFP48 package. This embodiment uses the STM32F103C8T6's SPI1 to communicate with the four IMU chips, and provides four chip select signals: CS1, CS2, CS3, and CS4. The processor connects the USART2 interface to the external communication interface 203 to transmit processed data.

[0054] In some embodiments of the present invention, the IMU array is composed of four ICM-20602 sensors. The ICM20602 is a 6-axis inertial sensor manufactured by TDK InvenSense. It combines a 3-axis gyroscope and a 3-axis accelerometer in an LGA package measuring only 3mm x 3mm.

[0055] In some embodiments of the present invention, the lithium battery charging management chip of the embodiment of the present invention is TP4057, which can automatically stop charging when the lithium battery voltage reaches the maximum charging voltage and indicate the current charging status to the outside through the charging status indicator light 209.

[0056] like Figure 8 As shown, the present application also provides a measurement method of the UAV thrust line measurement device based on the inertial measurement unit as described above, comprising:

[0057] First, install the PCB circuit board 2 with the IMU array welded on it onto the measuring tube mounting connector 1;

[0058] After the system is powered on, the processor communicates with the four IMU arrays through the SPI interface to collect the raw data of the IMU arrays;

[0059] Place the system on a horizontal surface, collect static data of the IMU array, and calculate the zero bias and scale factor of the IMU array based on the static data;

[0060] Writing the zero bias and scale factor of the IMU array into the processor, so as to correct the offline error of the raw data of the IMU array through the processor;

[0061] Based on the corrected raw data from the IMU array, the Allan variance algorithm is used to calculate the spectral density of the angle random walk and rate random walk of each IMU itself, as well as the spectral density correlation of the angle random walk and rate random walk between IMUs. Then, based on the spectral density correlation, the optimal linear combination weight of the IMU array gyroscope signal is calculated using the optimal linear weight estimation algorithm.

[0062] Among them, the embodiment of the present invention uses an algorithm proposed in the paper "Statistical Modeling of Rate Gyros" to estimate the spectral density of the angle random walk and rate random walk of a single gyroscope based on calculating the Allan variance of the gyroscope signal to estimate the spectral density of the angle random walk and rate random walk of each IMU.

[0063] Then, an optimal linear combination method for multi-gyro array data proposed in the paper "Reduced-Drift Virtual Gyro from an Array of Low-Cost Gyros" is used. By introducing a new statistic "Allan covariance", this method derives the angular random walk and rate random walk spectral density correlation matrices between the gyros, and calculates the optimal linear combination weights of each gyro in the gyro array.

[0064] Finally, the optimal linear combination weight is written into the processor to perform weighted fusion on the IMU array data through the processor to obtain fused attitude data, and finally the fused attitude data is converted into the position deviation value between the thrust line and the center of gravity. The weighted fusion algorithm is as follows:

[0065] IMU0=δ1*IMU1+δ2*IMU2+δ3*IMU3+δ4*IMU4

[0066] Among them, IMU0 is the final weighted fusion result, IMU1, IMU2, IMU3, and IMU4 are the outputs of the four IMUs respectively, and δ1, δ2, δ3, and δ4 are the weighted weights of the four IMUs respectively.

[0067] The algorithm for converting the weighted fusion data into the deviation value of the thrust line and the center of gravity position is as follows:

[0068]

[0069] Among them, Bias x 、Bias YIt is the component of the deviation between the thrust line and the center of gravity in the x and y directions; IMU 0x 、IMU 0x are the components of the weighted fusion result in the x and y directions, and L is the length of the measuring tube 5.

[0070] In summary, the UAV thrust line measurement solution based on a planar inertial measurement unit array described in the embodiment of the present invention can automatically obtain the deviation value between the UAV thrust line and the center of gravity by measuring the posture of the measuring barrel itself, thereby improving the measurement efficiency and accuracy.

[0071] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A UAV thrust line measurement device based on an inertial measurement unit, characterized in that: include: A measuring cylinder mounting and connecting seat, comprising a circular base plate and an annular side wall fixed to the circular base plate, so that the measuring cylinder mounting and connecting seat is disc-shaped as a whole, and further comprising a tubular connecting member, the tubular connecting member comprising a first section and a second section connected to each other, wherein the diameter of the first section is smaller than the diameter of the second section, a through hole is provided on the circular base plate, the tubular connecting member is fixed at the through hole, and the first section is located within the disc of the measuring cylinder mounting and connecting seat, so that an annular groove is formed within the measuring cylinder mounting and connecting seat, and the second section is located outside the disc of the measuring cylinder mounting and connecting seat; A PCB circuit board, the PCB circuit board is fixedly mounted in the annular groove of the measuring cylinder mounting connector, the PCB circuit board is provided with a processor, an IMU array, and an external communication interface, the IMU array is used to collect the attitude angle of the measuring cylinder, the processor is used to analyze and process the attitude angle data collected by the IMU array, and send the data to an external device through the external communication interface; A connecting seat upper cover, wherein a through hole is provided in the middle of the connecting seat upper cover, and the connecting seat upper cover is fixedly mounted on the measuring cylinder mounting connecting seat; The measuring cylinder and the suspension rod are fixedly connected to the top of the measuring cylinder and the second section of the tubular connector, and the bottom end of the measuring cylinder is fixed on the drone. The suspension rod passes through the measuring cylinder, the tubular connector and the upper cover of the connecting seat in sequence, and the drone is suspended at the bottom end of the suspension rod.

2. The UAV thrust line measurement device based on an inertial measurement unit according to claim 1, characterized in that: The IMU array consists of four pieces, and the four IMU chips are soldered on the PCB circuit board in a circular orthogonal arrangement.

3. The UAV thrust line measurement device based on an inertial measurement unit according to claim 1, characterized in that: The device also includes a 4.2V parallel lithium battery pack, and the PCB circuit board also includes a lithium battery power supply and charging interface and an LDO regulator. The 4.2V parallel lithium battery pack supplies power to the entire system through the lithium battery power supply and charging interface and the LDO regulator.

4. The UAV thrust line measurement device based on an inertial measurement unit according to claim 3, characterized in that: A charging hole is provided on the annular side wall of the measuring cylinder mounting connector for charging the 4.2V parallel lithium battery pack.

5. The UAV thrust line measurement device based on an inertial measurement unit according to claim 1, characterized in that: The PCB circuit board also includes a burning and debugging interface, a switch button, a lithium battery charging management chip, a Type-C charging port, a charging status indicator light, and a working status indicator light.

6. The UAV thrust line measurement device based on an inertial measurement unit according to claim 1, characterized in that: The connection seat upper cover is fixedly mounted on the measuring cylinder mounting connection seat by screws, and the PCB circuit board is fixedly mounted in the annular groove of the measuring cylinder mounting connection seat by screws.

7. The UAV thrust line measurement device based on an inertial measurement unit according to claim 1, characterized in that: The processor is STM32F103C8T6 in LQFP48 package.

8. A method for measuring a UAV thrust line measurement device based on an inertial measurement unit according to any one of claims 1 to 7, characterized in that: include: After the system is powered on, the processor communicates with the four IMU arrays through the SPI interface to collect the raw data of the IMU arrays; Calculate the zero bias and scale coefficient of the IMU array based on the static data of the IMU array; Writing the zero bias and scale factor of the IMU array into the processor, so as to correct the offline error of the raw data of the IMU array through the processor; Based on the corrected raw data of the IMU array, the spectral density of the angle random walk and the rate random walk of each IMU itself and the spectral density correlation of the angle random walk and the rate random walk between the IMUs are calculated using the Allan variance algorithm. Then, based on the spectral density correlation, the optimal linear combination weight of the IMU array gyroscope signal is calculated using the optimal linear weight estimation algorithm. The optimal linear combination weight is written into the processor so that the processor performs weighted fusion on the data of the IMU array to obtain fused attitude data. Finally, the fused attitude data is converted into thrust line measurement values ​​and output.

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