Thrust line measurement error analysis processing method based on suspension method

Abstract

The invention discloses a thrust line measurement error analysis processing method based on a suspension method, and belongs to the technical field of unmanned aerial vehicle design, and the method comprises the following steps: a, lifting an unmanned aerial vehicle from the abdomen of the unmanned aerial vehicle, connecting a lifting rope with the central axis of a thrust cone, and installing a double-shaft tilt angle sensor in a manner of being vertical to the central axis of the thrust cone; b, a system error, a random error and a gross error are obtained by comparing the measurement process with the state before the unmanned aerial vehicle is launched; and c, correcting system errors, evaluating random errors, and eliminating gross errors. According to the method, by comprehensively analyzing the error and quantitatively processing the error, the launching safety of the rocket-assisted launching unmanned aerial vehicle can be greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle (UAV) design, and particularly to a method for analyzing and processing measurement errors of a thrust line based on a suspension method. Background Art

[0002] When launching a UAV, the relative position relationship between the thrust line and the center of gravity is generally measured by a weighing method and a suspension method.

[0003] The weighing method is applicable to UAVs of all sizes, but it only measures the actual center of gravity of the UAV, without directly measuring the connection between the thrust line and the center of gravity, and requires more sensors, resulting in relatively large errors. The suspension method is generally only applicable to small and medium-sized UAVs. During the measurement process, the UAV generally needs to be flipped and lifted from the abdomen, and the measurement accuracy is relatively high. Since there are certain differences between the actual state of the UAV before launch and the measurement results of the thrust line, it is necessary to analyze and process the measurement errors.

[0004] The existing technology involves less analysis of the measurement errors of the thrust line based on the suspension method, and only qualitatively analyzes a single influencing factor. More research is focused on the measurement method.

[0005] Chinese patent document with publication number CN110398317A and publication date November 1, 2019 discloses a device and method for measuring the deviation between the center of gravity and the thrust line of a UAV. The device for measuring the deviation between the center of gravity and the thrust line of the UAV includes a cable for hanging the UAV; a thrust line measuring cylinder placed on the UAV, one end of the cable passes through the thrust line measuring cylinder and is connected to the UAV; and a deviation measuring seat connected to the measuring end of the thrust line measuring cylinder, the other end of the cable passes through the deviation measuring seat and is connected to a lifting device, and the deviation measuring seat is used to measure the deviation between the center of gravity and the thrust line of the UAV.

[0006] The device and method for measuring the deviation between the center of gravity and the thrust line of the UAV disclosed in this patent document solve the problems of difficult manual measurement and large measurement errors during the hanging process of the UAV. However, since the errors are not comprehensively analyzed and processed, the launch safety is not satisfactory. Summary of the Invention

[0007] In order to overcome the above defects of the prior art, the present invention provides a method for analyzing and processing measurement errors of a thrust line based on a suspension method. By comprehensively analyzing the errors and quantitatively processing the errors, the present invention can greatly improve the launch safety of a rocket-boosted launched UAV.

[0008] The present invention is realized by the following technical solutions: A method for analyzing and processing measurement errors of a thrust line based on a suspension method, characterized by comprising the following steps: a. Lift the UAV from the abdomen of the UAV, connect the lifting rope to the central axis of the thrust cone, and install the biaxial inclination sensor mounting surface perpendicular to the central axis of the thrust cone; b. Obtain systematic errors, random errors, and gross errors by comparing the measurement process with the state before the UAV is launched; c. Correct the systematic errors, evaluate the random errors, and eliminate the gross errors.

[0009] In step b, the systematic errors include errors of missing or overloading physical objects, fuel weight and center of gravity errors, rocket thrust deviation errors, sensor zero position errors, and structural deformation errors during measurement and launch.

[0010] In step c, correcting the systematic errors includes correcting errors of missing or overloading physical objects, fuel weight and center of gravity errors, rocket thrust deviation errors, sensor zero position errors, and structural deformation errors during measurement and launch.

[0011] The correction of the error of missing or overloading physical objects refers to calculating the coordinates of the center of gravity of the combined body after installing physical objects in the body coordinate system according to the center of gravity of the particle system, and then calculating the error correction amount.

[0012] The calculation of the center of gravity of the particle system is carried out by Equation 1; Equation 1; Where, is the coordinate of the center of gravity of the combined body after installing physical objects in the horizontal lateral direction in the body coordinate system, is the coordinate of the center of gravity of the combined body after installing physical objects in the horizontal longitudinal direction in the body coordinate system, is the coordinate of the center of gravity of the combined body after installing physical objects in the vertical direction in the body coordinate system, is the weight of the UAV in the measurement state, is the coordinate of the center of gravity of the UAV in the horizontal lateral direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the UAV in the horizontal longitudinal direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the UAV in the vertical direction in the body coordinate system during thrust line measurement, is the weight of the installed physical object, is the coordinate of the center of gravity of the installed physical object in the horizontal lateral direction in the body coordinate system, is the coordinate of the center of gravity of the installed physical object in the horizontal longitudinal direction in the body coordinate system, is the coordinate of the center of gravity of the installed physical object in the vertical direction in the body coordinate system.

[0013] The error correction amount is calculated by Equation 2 and Equation 3: Equation 2; Formula 3; Wherein, is the correction amount of the normal distance of the center of gravity relative to the thrust line caused by adding physical objects, is the correction amount of the lateral distance of the center of gravity relative to the thrust line caused by adding physical objects, is the rocket installation angle.

[0014] The fuel weight center of gravity error correction refers to determining the center of gravity position in the UAV launch state, and then calculating the correction amount of the change in the fuel center of gravity position in the launch state relative to the design state for the normal distance.

[0015] The rocket thrust deviation error correction refers to calculating the correction amount of the rocket thrust deviation error for the normal distance and the correction amount of the rocket thrust deviation error for the lateral distance respectively through Formula 4 and Formula 5 and the correction amount of the rocket thrust deviation error for the lateral distance ; Formula 4; Formula 5; Wherein, is the distance of the thrust line transverse movement in the normal direction, is the distance of the lateral movement, is the theoretical distance from the launch interface to the center of gravity, is the angle of the thrust line skew movement in the normal direction, is the angle of the lateral movement.

[0016] The sensor zero position error correction refers to installing the biaxial inclinometer sensor on the thrust cone, fixing the thrust cone on the vise, reading and recording the indicated values (X1, Y1), removing the biaxial inclinometer sensor from the thrust cone, rotating it 180° and then reinstalling it, reading and recording the indicated values (X2, Y2), and respectively calculating the angle of the biaxial inclinometer sensor zero position error affecting the normal distance , the angle of the biaxial inclinometer sensor zero position error affecting the lateral distance , the biaxial inclinometer sensor zero position error affecting the normal distance and the biaxial inclinometer sensor zero position error affecting the lateral distance ; Formula 6; Formula 7; Formula 8; Formula 9; Wherein, is the theoretical distance from the launch interface to the center of gravity, X1 is the first lateral value, Y1 is the first normal value, X2 is the second lateral value, and Y2 is the second normal value.

[0017] The structural deformation error correction during measurement and launch refers to determining the rotation angle of the thrust line caused by the structural deformation of the UAV during the thrust line measurement, obtaining the normal distance caused by the structural deformation of the UAV during launch according to the proportional relationship between the rocket thrust and the gravity of the UAV, and finally determining the structural deformation error correction amount during measurement and launch.

[0018] In step c, evaluating the random error means measuring the magnitude of the random error through the standard error; Equation 10; Among them, is the number of measurements of the angle during the thrust line measurement, is the standard deviation of the n measurement results.

[0019] In step c, eliminating the gross error means screening the data of all measurement results through the Chauvenet's criterion, judging the data containing the gross error and eliminating it from the measurement result sample; Equation 11; Among them, is the th thrust line measurement result, is the mean of the multiple measurement results, and is the standard deviation of the multiple measurement results.

[0020] The beneficial effects of the present invention are mainly manifested in the following aspects: 1. In the present invention, a. Lift the UAV from the abdomen of the UAV, connect the suspension rope to the central axis of the thrust cone, and install the biaxial inclination sensor surface perpendicular to the central axis of the thrust cone; b. By comparing the measurement process with the state before the UAV is launched, obtain the systematic error, random error and gross error; c. Correct the systematic error, evaluate the random error, and eliminate the gross error. Compared with the prior art, by comprehensively analyzing the error and quantitatively processing the error, the launch safety of the rocket-boosted launch UAV can be greatly improved.

[0021] 2. In the present invention, the difference between the thrust line measurement result and the state before the actual launch of the UAV is greatly reduced, and it is applicable to multiple types of rocket-boosted launch UAVs.

[0022] 3. In the present invention, the matching relationship between the center of gravity and the thrust line during the launch of the UAV can be effectively guaranteed, and the reliability of successful launch can be improved.

[0023] 4. In the present invention, the main differences between the state before the actual launch of the rocket-boosted launch UAV and the thrust line measurement result are fully analyzed, and each error is quantitatively processed, which can be directly used to guide the thrust line adjustment. Description of the Drawings

[0024] The present invention will be further specifically described below in conjunction with the accompanying drawings of the specification and the specific embodiments: Figure 1 is a flow block diagram of the present invention; Figure 2 is a schematic diagram of the thrust line measurement structure of the present invention; Reference numerals in the figures: 1, suspension rope; 2, thrust cone; 3, biaxial inclination sensor. Specific embodiments

[0025] Embodiment 1 Refer to Figure 1 and Figure 2 , a method for analyzing and processing thrust line measurement errors based on the suspension method, comprising the following steps: a. Lift the unmanned aerial vehicle from the abdomen of the unmanned aerial vehicle, connect the suspension rope 1 to the central axis of the thrust cone 2, and vertically install the mounting surface of the biaxial inclination sensor 3 perpendicular to the central axis of the thrust cone 2; b. Obtain systematic errors, random errors, and gross errors by comparing the measurement process with the state before the launch of the unmanned aerial vehicle; c. Correct the systematic errors, evaluate the random errors, and eliminate the gross errors.

[0026] This embodiment is the most basic implementation mode. By comprehensively analyzing the errors and quantitatively processing the errors, the launch safety of the rocket-boosted unmanned aerial vehicle can be greatly improved.

[0027] Embodiment 2 Refer to Figure 1 and Figure 2 , a method for analyzing and processing thrust line measurement errors based on the suspension method, comprising the following steps: a. Lift the unmanned aerial vehicle from the abdomen of the unmanned aerial vehicle, connect the suspension rope 1 to the central axis of the thrust cone 2, and vertically install the mounting surface of the biaxial inclination sensor 3 perpendicular to the central axis of the thrust cone 2; b. Obtain systematic errors, random errors, and gross errors by comparing the measurement process with the state before the launch of the unmanned aerial vehicle; c. Correct the systematic errors, evaluate the random errors, and eliminate the gross errors.

[0028] In step b, the systematic errors include errors of missing or overloading physical objects, fuel weight and center-of-gravity errors, rocket thrust deviation errors, sensor zero-position errors, and structural deformation errors during measurement and launch.

[0029] In step c, correcting the systematic errors includes correcting errors of missing or overloading physical objects, fuel weight and center-of-gravity errors, rocket thrust deviation errors, sensor zero-position errors, and structural deformation errors during measurement and launch.

[0030] The missing or overloaded physical error correction refers to calculating the coordinates of the combined center of gravity in the body coordinate system after adding physical objects according to the center of gravity of the particle system, and then calculating the error correction amount.

[0031] The calculation of the center of gravity of the particle system is carried out by Equation 1; Equation 1; Where, is the coordinate of the combined center of gravity in the horizontal lateral direction in the body coordinate system after adding physical objects, is the coordinate of the combined center of gravity in the horizontal longitudinal direction in the body coordinate system after adding physical objects, is the coordinate of the combined center of gravity in the vertical direction in the body coordinate system after adding physical objects, is the weight of the unmanned aerial vehicle in the measurement state, is the coordinate of the center of gravity of the unmanned aerial vehicle in the horizontal lateral direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the unmanned aerial vehicle in the horizontal longitudinal direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the unmanned aerial vehicle in the vertical direction in the body coordinate system during thrust line measurement, is the weight of the added physical object, is the coordinate of the center of gravity of the added physical object in the horizontal lateral direction in the body coordinate system, is the coordinate of the center of gravity of the added physical object in the horizontal longitudinal direction in the body coordinate system, is the coordinate of the center of gravity of the added physical object in the vertical direction in the body coordinate system.

[0032] The error correction amount is calculated by Equation 2 and Equation 3: Equation 2; Equation 3; Where, is the correction amount of the normal distance of the center of gravity relative to the thrust line caused by adding physical objects, is the correction amount of the lateral distance of the center of gravity relative to the thrust line caused by adding physical objects, is the rocket installation angle.

[0033] The fuel weight center of gravity error correction refers to determining the center of gravity position of the unmanned aerial vehicle in the launch state, and then calculating the correction amount of the change in the fuel center of gravity position in the launch state relative to the design state for the normal distance.

[0034] This embodiment is a preferred embodiment, which greatly reduces the difference between the thrust line measurement result and the actual pre-launch state of the unmanned aerial vehicle, and is applicable to multiple types of rocket-boosted launch unmanned aerial vehicles.

[0035] Embodiment 3 See Figure 1 andFigure 2 , a method for analyzing and processing the measurement error of the thrust line based on the suspension method, comprising the following steps: a. Lift the unmanned aerial vehicle from the abdomen of the unmanned aerial vehicle, connect the suspension rope 1 to the central axis of the thrust cone 2, and install the mounting surface of the biaxial inclination sensor 3 perpendicular to the central axis of the thrust cone 2; b. Obtain the systematic error, random error, and gross error by comparing the measurement process with the state before the launch of the unmanned aerial vehicle; c. Correct the systematic error, evaluate the random error, and eliminate the gross error.

[0036] In the step b, the systematic error includes the error of missing or adding physical objects, the error of the fuel weight and center of gravity, the deviation error of the rocket thrust, the zero position error of the sensor, and the structural deformation error during measurement and launch.

[0037] In the step c, correcting the systematic error includes correcting the error of missing or adding physical objects, correcting the error of the fuel weight and center of gravity, correcting the deviation error of the rocket thrust, correcting the zero position error of the sensor, and correcting the structural deformation error during measurement and launch.

[0038] The correction of the error of missing or adding physical objects means calculating the coordinates of the center of gravity of the combined body after adding physical objects in the body coordinate system according to the center of gravity of the particle system, and then calculating the error correction amount.

[0039] The calculation of the center of gravity of the particle system is calculated by Equation 1; Equation 1; Where is the coordinate of the center of gravity of the combined body after adding physical objects in the horizontal lateral direction in the body coordinate system, is the coordinate of the center of gravity of the combined body after adding physical objects in the horizontal longitudinal direction in the body coordinate system, is the coordinate of the center of gravity of the combined body after adding physical objects in the vertical direction in the body coordinate system, is the weight of the unmanned aerial vehicle in the measurement state, is the coordinate of the center of gravity of the unmanned aerial vehicle in the horizontal lateral direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the unmanned aerial vehicle in the horizontal longitudinal direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the unmanned aerial vehicle in the vertical direction in the body coordinate system during thrust line measurement, is the weight of the added physical object, is the coordinate of the center of gravity of the added physical object in the horizontal lateral direction in the body coordinate system, is the coordinate of the center of gravity of the added physical object in the horizontal longitudinal direction in the body coordinate system, is the coordinate of the center of gravity of the added physical object in the vertical direction in the body coordinate system.

[0040] The error correction amount is calculated by Equations 2 and 3: Equation 2; Equation 3; Wherein, is the correction amount of the normal distance of the center of gravity relative to the thrust line caused by installing the physical object, is the correction amount of the lateral distance of the center of gravity relative to the thrust line caused by installing the physical object, is the rocket installation angle.

[0041] The fuel weight center of gravity error correction refers to determining the center of gravity position in the UAV launch state, and then calculating the correction amount of the change in the fuel center of gravity position in the launch state relative to the design state for the normal distance.

[0042] The rocket thrust deviation error correction refers to calculating the correction amount of the rocket thrust deviation error for the normal distance and the correction amount of the rocket thrust deviation error for the lateral distance respectively by Equations 4 and 5; Equation 4; Equation 5; Wherein, is the distance of the thrust line transverse movement in the normal direction, is the distance of the lateral movement, is the theoretical distance from the launch interface to the center of gravity, is the angle of the thrust line skew movement in the normal direction, is the angle of the lateral movement.

[0043] The sensor zero position error correction refers to after installing the biaxial inclinometer sensor 3 on the thrust cone 2, fixing the thrust cone 2 in the vise, reading and recording the indication values (X1, Y1), removing the biaxial inclinometer sensor 3 from the thrust cone 2, rotating it 180° and then reinstalling it, reading and recording the indication values (X2, Y2), and respectively calculating the angle of the biaxial inclinometer sensor zero position error affecting the normal distance, the angle of the biaxial inclinometer sensor zero position error affecting the lateral distance, the biaxial inclinometer sensor zero position error affecting the normal distance and the biaxial inclinometer sensor zero position error affecting the lateral distance; Equation 6; Equation 7; Equation 8; Equation 9; Wherein, is the theoretical distance from the launch interface to the center of gravity, X1 is the first transverse value, Y1 is the first normal value, X2 is the second transverse value, and Y2 is the second normal value.

[0044] The structural deformation error correction during measurement and launch refers to determining the rotation angle of the thrust line caused by the structural deformation of the UAV during thrust line measurement, obtaining the normal distance caused by the structural deformation of the UAV during launch according to the proportional relationship between the rocket thrust and the gravity of the UAV, and finally determining the structural deformation error correction amount during measurement and launch.

[0045] This embodiment is another preferred embodiment, which can effectively ensure the matching relationship between the center of gravity and the thrust line of the UAV during launch and improve the reliability of successful launch.

[0046] Embodiment 4 See Figure 1 and Figure 2 , a method for analyzing and processing the measurement error of the thrust line based on the suspension method, including the following steps: a. Hang the UAV from the abdomen of the UAV, connect the suspension rope 1 to the central axis of the thrust cone 2, and install the biaxial inclination sensor 3 perpendicular to the central axis of the thrust cone 2; b. By comparing the measurement process with the state of the UAV before launch, obtain the systematic error, random error, and gross error; c. Correct the systematic error, evaluate the random error, and eliminate the gross error.

[0047] In the step b, the systematic error includes the error of missing or adding physical objects, the error of the fuel weight center of gravity, the error of the rocket thrust deviation, the zero position error of the sensor, and the structural deformation error during measurement and launch.

[0048] In the step c, the correction of the systematic error includes the correction of the error of missing or adding physical objects, the correction of the fuel weight center of gravity error, the correction of the rocket thrust deviation error, the correction of the sensor zero position error, and the correction of the structural deformation error during measurement and launch.

[0049] The correction of the error of missing or adding physical objects refers to calculating the coordinates of the center of gravity of the combined body after adding physical objects in the body coordinate system according to the center of gravity calculation of the particle system, and then calculating the error correction amount.

[0050] The calculation of the center of gravity of the particle system is calculated by Equation 1; Equation 1; Among them, is the coordinate of the center of gravity of the combined body after adding physical objects in the horizontal transverse direction in the body coordinate system, is the coordinate of the center of gravity of the combined body after adding physical objects in the horizontal longitudinal direction in the body coordinate system, is the vertical coordinate of the combined center of gravity in the body coordinate system after adding physical objects. is the weight of the UAV in the measurement state. is the horizontal lateral coordinate of the UAV's center of gravity in the body coordinate system during thrust line measurement. is the horizontal longitudinal coordinate of the UAV's center of gravity in the body coordinate system during thrust line measurement. is the vertical coordinate of the UAV's center of gravity in the body coordinate system during thrust line measurement. is the weight of the added physical object. is the horizontal lateral coordinate of the center of gravity of the added physical object in the body coordinate system. is the horizontal longitudinal coordinate of the center of gravity of the added physical object in the body coordinate system. is the vertical coordinate of the center of gravity of the added physical object in the body coordinate system.

[0051] The error correction amount is calculated by Equation 2 and Equation 3: Equation 2; Equation 3; Among them, is the correction amount of the normal distance of the center of gravity relative to the thrust line caused by adding physical objects. is the correction amount of the lateral distance of the center of gravity relative to the thrust line caused by adding physical objects. is the rocket installation angle.

[0052] The fuel weight center of gravity error correction refers to determining the center of gravity position of the UAV in the launch state, and then calculating the correction amount of the change in the fuel center of gravity position in the launch state relative to the design state for the normal distance.

[0053] The rocket thrust deviation error correction refers to calculating the correction amount of the rocket thrust deviation error for the normal distance and the correction amount of the rocket thrust deviation error for the lateral distance respectively through Equation 4 and Equation 5 ; Equation 4; Equation 5; Among them, is the distance of the thrust line transverse shift in the normal direction. is the distance of the lateral movement. is the theoretical distance from the launch interface to the center of gravity. is the angle of the thrust line skew in the normal direction movement. is the angle of the lateral movement.

[0054] The correction of the zero - position error of the sensor means that after the biaxial inclination sensor 3 is installed on the thrust cone 2, the thrust cone 2 is fixed on the bench vice, the indicated values (X1, Y1) are read and recorded. Then the biaxial inclination sensor 3 is removed from the thrust cone 2, rotated 180° and reinstalled, and the indicated values (X2, Y2) are read and recorded. The angles affecting the normal distance and the lateral distance caused by the zero - position error of the biaxial inclination sensor are calculated respectively. and the angle affecting the lateral distance caused by the zero - position error of the biaxial inclination sensor ; the influence of the zero - position error of the biaxial inclination sensor on the normal distance and the influence of the zero - position error of the biaxial inclination sensor on the lateral distance ; Equation 6; Equation 7; Equation 8; Equation 9; Among them, is the theoretical distance from the launch interface to the center of gravity, X1 is the first lateral value, Y1 is the first normal value, X2 is the second lateral value, and Y2 is the second normal value.

[0055] The correction of the structural deformation error during measurement and launch means determining the rotation angle of the thrust line caused by the structural deformation of the UAV during thrust line measurement, obtaining the normal distance caused by the structural deformation of the UAV during launch according to the proportional relationship between the rocket thrust and the gravity of the UAV, and finally determining the correction amount of the structural deformation error during measurement and launch.

[0056] In step c, the evaluation of the random error means measuring the size of the random error through the standard error; Equation 10; Among them, is the number of measurements of the angle during thrust line measurement, is the standard deviation of the n - th measurement result.

[0057] In step c, the rejection of the gross error means screening all the measurement results through the Chauvenet's criterion, judging the data containing gross errors and removing them from the measurement result sample; Equation 11; Among them, is the -th thrust line measurement result, is the mean value of the multiple measurement results, and is the standard deviation of the multiple measurement results.

[0058] This embodiment is the optimal implementation mode, which fully analyzes the main differences between the state of the rocket-boosted launch UAV before actual launch and the results of thrust line measurement, and quantitatively processes each error, and can be directly used to guide the adjustment of the thrust line.

[0059] The process of matching the rocket thrust line with the UAV's center of gravity during launch is as follows: S1. Measure the thrust line of the UAV based on the suspension method, and obtain the original angle and original distance. Eliminate the gross error according to Equation 11. S2. Evaluate the random error of the measured data after elimination according to Equation 10. If the measured random error is less than the allowable values of the UAV for the normal distance and lateral distance errors, the measurement result is valid. S3. According to the correction of the systematic error, calculate the total correction amount of the normal distance as: Calculate the total correction amount of the normal distance as: S4. The normal distance during thrust line measurement is , and the lateral distance during thrust line measurement is . Calculate the corrected normal distance: Calculate the corrected lateral distance: S5. According to and Adjust the thrust line to make the rocket thrust line match the UAV's center of gravity during launch.

Claims

1. A method for analyzing and processing the measurement error of the thrust line based on the suspension method, characterized in that It includes the following steps: a. Lift the drone from the abdomen of the drone, connect the lifting rope (1) to the central axis of the thrust cone (2), and install the mounting surface of the biaxial inclination sensor (3) perpendicular to the central axis of the thrust cone (2); b. Obtain the systematic error, random error, and gross error by comparing the measurement process with the state before the drone is launched; c. Correct the systematic error, evaluate the random error, and eliminate the gross error.

2. The method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 1, wherein: In step b, the systematic error includes the error of missing or overloading physical objects, the error of fuel weight and center of gravity, the deviation error of rocket thrust, the zero position error of the sensor, and the structural deformation error during measurement and launch.

3. A method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 2, characterized in that: In step c, correcting the systematic error includes correcting the error of missing or overloading physical objects, correcting the error of fuel weight and center of gravity, correcting the deviation error of rocket thrust, correcting the zero position error of the sensor, and correcting the structural deformation error during measurement and launch.

4. The method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 3, wherein: The correction of the error of missing or overloading physical objects refers to calculating the coordinates of the center of gravity of the combined body after adding physical objects in the body coordinate system according to the center of gravity of the particle system, and then calculating the error correction amount.

5. A method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 4, characterized in that: The calculation of the center of gravity of the particle system refers to the calculation through Equation 1; Formula 1; Among them, is the coordinate of the center of gravity of the combined body in the horizontal lateral direction in the body coordinate system after installing the physical object, is the coordinate of the center of gravity of the combined body in the horizontal longitudinal direction in the body coordinate system after installing the physical object, is the coordinate of the center of gravity of the combined body in the vertical direction in the body coordinate system after installing the physical object, is the weight of the UAV in the measurement state, is the coordinate of the center of gravity of the UAV in the horizontal lateral direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the UAV in the horizontal longitudinal direction in the body coordinate system during thrust line measurement, is the coordinate of the center of gravity of the UAV in the vertical direction in the body coordinate system during thrust line measurement, is the weight of the installed physical object, is the coordinate of the center of gravity of the installed physical object in the horizontal lateral direction in the body coordinate system, is the coordinate of the center of gravity of the installed physical object in the horizontal longitudinal direction in the body coordinate system, is the coordinate of the center of gravity of the installed physical object in the vertical direction in the body coordinate system.

6. A method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 4, characterized in that: The error correction amount is calculated through Equation 2 and Equation 3: Formula 2; Formula 3; Among them, is the correction amount of the normal distance of the center of gravity relative to the thrust line caused by adding physical objects, is the correction amount of the lateral distance of the center of gravity relative to the thrust line caused by adding physical objects, is the rocket installation angle.

7. A method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 3, characterized in that: The correction of the rocket thrust deviation error refers to calculating the correction amount of the rocket thrust deviation error for the normal distance and the correction amount of the rocket thrust deviation error for the lateral distance respectively through Equation 4 and Equation 5 and ; Formula 4; Formula 5; Among them, is the distance of the transverse movement of the thrust line in the normal direction, is the distance of the lateral movement, is the theoretical distance between the launch interface and the center of gravity, is the angle of the transverse movement of the thrust line in the normal direction, is the angle of the lateral movement.

8. A method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 3, characterized in that: The zero position error correction of the sensor means that after the biaxial inclination sensor (3) is installed on the thrust cone (2), the thrust cone (2) is fixed on the vise, the indicated values (X1, Y1) are read and recorded, the biaxial inclination sensor (3) is removed from the thrust cone (2), rotated 180°, and then reinstalled, and the indicated values (X2, Y2) are read and recorded, and the angles of the zero position error of the biaxial inclination sensor affecting the normal distance, the angles of the zero position error of the biaxial inclination sensor affecting the lateral distance, the zero position error of the biaxial inclination sensor affecting the normal distance, and the zero position error of the biaxial inclination sensor affecting the lateral distance ; Formula 6; Formula 7; Formula 8; Formula 9; wherein, is the theoretical distance from the emission interface to the center of gravity, X1 is the first lateral value, Y1 is the first normal value, X2 is the second lateral value, and Y2 is the second normal value.

9. A method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 1, characterized in that: In step c, evaluating the random error refers to measuring the magnitude of the random error through the standard error; Formula 10; Among them, is the number of measurements of the angle in the thrust line measurement, is the standard deviation of the results of n measurements.

10. A method for analyzing and processing the measurement error of the thrust line based on the suspension method according to claim 1, characterized in that: In step c, eliminating the gross error refers to screening the data through the Chauvenet's criterion for all measurement results, judging the data containing gross error and eliminating it from the measurement result sample; Formula 11; Among them, is the th thrust line measurement result, is the mean of multiple measurement results, and is the standard deviation of multiple measurement results.

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