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

Abstract

The invention provides an unmanned aerial vehicle thrust line measuring device and method based on an inertial measurement unit, and the device comprises a measuring cylinder installation connecting seat which comprises a circular bottom plate and an annular side wall, and also comprises a tubular connecting piece which comprises a first section and a second section which are connected with each other, the circular bottom plate is provided with a through hole, and the tubular connecting piece is fixed at the through hole; the PCB is installed in the connecting base, a processor, an IMU array and an external communication interface are arranged on the PCB, the IMU array is used for collecting the attitude angle of the measuring cylinder, and the processor is used for analyzing and processing data and outputting the data through the external communication interface; the upper cover is fixedly mounted on the connecting seat; the top end of the measuring cylinder is fixed to the second section of the connecting piece, the bottom end of the measuring cylinder is fixed to the unmanned aerial vehicle, the suspender sequentially penetrates through the measuring cylinder, the connecting piece and the upper cover, and the unmanned aerial vehicle is hung at the bottom end of the suspender. According to the invention, the automation of the measurement process is realized, the measurement data can be traced back, and the measurement efficiency and the measurement precision are improved.

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 based on an inertial measurement unit. Background Art

[0002] Rocket-assisted launch is an important part of the UAV flight process. The UAV relies on its own power and the thrust generated by the rocket booster to accelerate from a stationary state to a safe flight speed and altitude. After the rocket booster separates, the UAV enters the flight route under its own power. The speed of the UAV during takeoff is determined by the thrust of the booster rocket and the engine, and the stability of the takeoff process is determined by the pitch angle of the aircraft. The measurement accuracy of the thrust line is a key factor in the successful launch of the UAV.

[0003] At present, the thrust line of the rocket-assisted zero-length launch drone is basically measured by hanging. The hanging of the drone is achieved 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 seat 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 the problems of cumbersome operation, large measurement error, long measurement time, etc., and the automation of data reading and processing is not realized.

[0004] In addition, the current measurement process is mainly carried out manually through measuring tools such as steel rulers and calipers (such as the prior art 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 the UAV launch to fail. 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 embodiment of 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 installation connection seat, the measuring cylinder installation connection seat comprises a circular bottom plate and an annular side wall fixed on the circular bottom plate, so that the measuring cylinder installation connection seat is in the shape of a disc as a whole, the measuring cylinder installation connection seat also comprises a tubular connection member, the tubular connection member comprises a first section and a second section connected to each other, and the tube diameter of the first section is smaller than the tube diameter of the second section, a through hole is provided on the circular bottom plate, the tubular connection member is fixed at the through hole, and the first section is located in the disc of the measuring cylinder installation connection seat, so that an annular groove is formed in the measuring cylinder installation connection seat, and the second section is located outside the disc of the measuring cylinder installation connection 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 connection seat upper cover, wherein a through hole is provided in the middle of the connection seat upper cover, and the connection seat upper cover is fixedly mounted on the measuring tube mounting connection seat;

[0010] A measuring tube and a suspension rod, wherein the top end of the measuring tube is fixedly connected to the second section of the tubular connector, the bottom end of the measuring tube is fixed on the drone, the suspension rod passes through the measuring tube, 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 supplies power to 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 tube 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 an embodiment of the present application, the processor is STM32F103C8T6 in LQFP48 package.

[0017] 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:

[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] According to the static data of the IMU array, calculate the zero bias and scale coefficient of the IMU array;

[0020] Writing the zero bias and the scale coefficient 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] According to the corrected original 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 by the Allan variance algorithm, and then according to the spectral density correlation, the optimal linear combination weight of the IMU array gyroscope signal is calculated by the optimal linear weight estimation algorithm; the optimal linear combination weight is written into the processor, so that the data of the IMU array is weightedly fused through the processor to obtain fused attitude data, and finally the fused attitude data is converted into thrust line measurement values ​​and output.

[0022] Existing UAV thrust line measurement devices are based on the hanging method, relying on mechanical measuring instruments and manual reading methods to perform measurements, which are lacking in accuracy and efficiency of data reading. Compared with the prior art, the beneficial effects that can be achieved by at least one of the above technical solutions adopted in the embodiments of this specification include at least:

[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, avoiding direct contact between personnel and measuring equipment such as steel rulers and calipers and the measuring tube and cables or booms, reducing 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 drawings required for use in the embodiments will be briefly introduced below. 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 paying creative work.

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

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

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

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

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

[0031] Figure 6a It is a schematic diagram of the upper cover structure of the measuring cylinder mounting connection seat according to an embodiment of the present invention;

[0032] Figure 6b It is another structural schematic diagram of the upper cover of the measuring cylinder mounting connection seat 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 installation connector; 2. PCB circuit board; 3. 4.2V parallel lithium battery pack; 4. Connecting seat cover; 5. Measuring tube; 101. First mounting screw hole; 102. Second mounting screw hole; 103. Tightening screw hole; 104. Charging hole; 201. Processor chip; 202. IMU array; 203. External communication interface (can connect 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 light; 210. Working status indicator light; 211. LDO regulator; 212. PCB mounting hole; 401. Upper 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 implementation methods 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 implementation methods, 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 following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present 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 the present 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 the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device 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 drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0040] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the aspects described may be practiced without these specific details.

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

[0042] The existing technologies all use the hanging method to measure the thrust line of the UAV, and directly measure the difference between the center of gravity of the UAV and the thrust line through external measuring instruments and equipment. Since the cable or boom always passes through the center of gravity of the UAV and is plumb with the ground during the hanging process, the measurement of the difference between the center of gravity and the thrust line of the UAV 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 UAV thrust line measurement scheme 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 the thrust line of UAVs.

[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 connection seat 1, the measuring cylinder mounting connection seat 1 comprises a circular bottom plate and an annular side wall fixed on the circular bottom plate, so that the measuring cylinder mounting connection seat 1 is disc-shaped as a whole, the measuring cylinder mounting connection seat 1 also comprises a tubular connecting member, the tubular connecting member comprises a first section and a second section connected to each other, and the diameter of the first section is smaller than the diameter of the second section, a through hole is provided on the circular bottom plate, the tubular connecting member is fixed at the through hole, and the first section is located in the disc of the measuring cylinder mounting connection seat 1, so that an annular groove is formed in the measuring cylinder mounting connection seat 1, and the second section is located outside the disc of the measuring cylinder mounting connection seat 1;

[0045] PCB circuit board 2, the PCB circuit board 2 is fixedly mounted in the annular groove of the measuring cylinder mounting connector 1, the PCB circuit board 2 is 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, the processor is used to analyze and process the attitude angle data collected by the IMU array 202, and send the data to an external device through the external communication interface;

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

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

[0048] In some embodiments of the present invention, Figure 3a and 3bAs shown, the connection seat upper cover 4 is fixedly mounted on the opening of the measuring cylinder mounting connection seat 1, so that the measuring cylinder 5 mounting connection seat 1 and the connection seat upper cover 4 together constitute a shell structure for accommodating the PCB circuit board 2. Among them, the edge of the measuring cylinder mounting connection seat 1 evenly extends outward with a plurality of first mounting screw holes 101, and the connection seat upper cover 4 is correspondingly provided with upper cover mounting holes 401, so that the connection seat upper cover 4 and the measuring cylinder mounting connection seat 1 are fixedly mounted by screws through the first mounting screw holes 101 and the upper cover mounting holes 401. The PCB circuit board 2 is fixedly mounted in the annular groove of the measuring cylinder mounting connection seat 1. Among them, the inner side of the annular side wall of the measuring cylinder mounting connection seat 1 is evenly spaced with a plurality of second mounting screw holes 102, and the PCB circuit board 2 is provided with a plurality of PCB mounting holes 212, and the second mounting screw holes 102 correspond to the positions of the PCB mounting holes 212, so as to be fixedly connected by screws. The second section of the tubular connector is fixed on the measuring cylinder 5 through the set screw hole 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 is mainly composed 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 light 209, a working status indicator light 210, and an LDO regulator 211. The components and their auxiliary devices 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 outside world plugs a universal USB to Type-C power cord into the Type-C charging port 208, and charges the 4.2V parallel lithium battery pack 3 through a lithium battery charging management chip 207, and a 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 key switch 206 through the key 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 of the embodiment of the present invention uses the processor chip 201 of STM32F103C8T6 in LQFP48 package. In the embodiment of the present invention, SPI1 of STM32F103C8T6 is used to communicate with four IMU chips, and four chip select signals CS1, CS2, CS3, and CS4 are set. The processor connects the USART2 interface to the external communication interface 203 and sends the processed data to the outside.

[0054] In some embodiments of the present invention, the IMU array of the embodiment of the present invention is composed of four ICM-20602s. ICM20602 is a 6-axis inertial sensor produced by TDK InvenSense. It combines a three-axis gyroscope and a three-axis accelerometer, and is packaged in LGA format with a size of only 3mm×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 plane, collect static data of the IMU array, and calculate the zero bias and scale coefficient of the IMU array based on the static data;

[0060] Writing the zero bias and the scale coefficient 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] According to the corrected original data of the IMU array, the spectral density of the angle random walk and rate random walk of each IMU itself and the spectral density correlation of the angle random walk and rate random walk between the IMUs are calculated by the Allan variance algorithm, and then according to the spectral density correlation, the optimal linear combination weight of the IMU array gyroscope signal is calculated by the optimal linear weight estimation algorithm.

[0062] Among them, an embodiment of the present invention utilizes an algorithm proposed in the article "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, and estimates the spectral density of the angle random walk and rate random walk of each IMU.

[0063] Then, an optimal linear combination method for data of a multi-gyroscope array proposed in the paper "Reduced-Drift Virtual Gyro from an Array of Low-Cost Gyros" is used. This method introduces a new statistic called "Allan covariance" to derive the spectral density correlation matrix of the angle random walk and rate random walk between the gyroscopes, and calculates the optimal linear combination weights of each gyroscope in the gyroscope array.

[0064] Finally, the optimal linear combination weight is written into the processor to perform weighted fusion on the data of the IMU array through the processor to obtain fused attitude data, and finally the fused attitude data is converted into the position deviation value of 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 scheme based on a planar inertial measurement unit array described in an 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 is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A UAV thrust line measurement device based on an inertial measurement unit, characterized in that: include: A measuring cylinder installation connection seat, the measuring cylinder installation connection seat comprises a circular bottom plate and an annular side wall fixed on the circular bottom plate, so that the measuring cylinder installation connection seat is in the shape of a disc as a whole, the measuring cylinder installation connection seat also comprises a tubular connection member, the tubular connection member comprises a first section and a second section connected to each other, and the tube diameter of the first section is smaller than the tube diameter of the second section, a through hole is provided on the circular bottom plate, the tubular connection member is fixed at the through hole, and the first section is located in the disc of the measuring cylinder installation connection seat, so that an annular groove is formed in the measuring cylinder installation connection seat, and the second section is located outside the disc of the measuring cylinder installation connection 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 connection seat upper cover, wherein a through hole is provided in the middle of the connection seat upper cover, and the connection seat upper cover is fixedly mounted on the measuring tube mounting connection seat; A measuring tube and a suspension rod, wherein the top end of the measuring tube is fixedly connected to the second section of the tubular connector, the bottom end of the measuring tube is fixed on the drone, the suspension rod passes through the measuring tube, 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 welded 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 is characterized in that: A charging hole is provided on the annular side wall of the measuring tube 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 installation connection seat by screws, and the PCB circuit board is fixedly mounted in the annular groove of the measuring cylinder installation 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 thrust line measurement device of an unmanned aerial vehicle 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; According to the static data of the IMU array, calculate the zero bias and scale coefficient of the IMU array; Writing the zero bias and the scale coefficient 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; According to the corrected original 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 by the Allan variance algorithm, and then according to the spectral density correlation, the optimal linear combination weight of the gyro signal of the IMU array is calculated by the optimal linear weight estimation algorithm; the optimal linear combination weight is written into the processor, so that the data of the IMU array is weightedly fused through the processor to obtain fused attitude data, and finally the fused attitude data is converted into thrust line measurement values ​​and output.

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