Device and method for measuring and adjusting thrust line of double-rocket boosting unmanned aerial vehicle

Abstract

The invention discloses a double-rocket boosting unmanned aerial vehicle thrust line measurement and adjustment device and method, and belongs to the technical field of unmanned aerial vehicle assembly and measurement. The device does not need a counterweight, can realize direct measurement of double thrust lines, is reliable in precision, realizes high-precision measurement of the thrust lines of the double-rocket boosting unmanned aerial vehicle and effective adjustment of symmetry of the thrust lines relative to a plane where the center of mass is located through a thrust line measurement and adjustment method established by the device, improves the launching performance and flight safety of the unmanned aerial vehicle, and is suitable for popularization and application. Therefore, the problems that in the prior art, the measurement direction of the thrust line of the double-rocket boosting unmanned aerial vehicle cannot be directly measured with high precision, and the actual mass center of the unmanned aerial vehicle cannot be effectively located on the symmetry plane of the rocket through trim adjustment are solved. The device and the method can be suitable for the small-batch trial-manufacture measurement and adjustment process of various different unmanned aerial vehicles, and are high in universality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicle assembly and measurement, in particular to a thrust line measurement and adjustment device applied to a double-rocket boost unmanned aerial vehicle and a method thereof. BACKGROUND

[0002] With the advantages of reducing personnel risk, low cost, strong task execution ability and good operability, unmanned aerial vehicles have been widely used in military and civilian fields in recent years. Rocket launch has become one of the important take-off methods due to its characteristics of not relying on runway and flexible use. The thrust generated by the rocket booster provides the initial height and speed for the unmanned aerial vehicle. Compared with the single-rocket boost scheme, the double-rocket boost system has a larger initial thrust, a more stable launch attitude, and a lower layout requirement for the tail space of the vehicle body, and its application range continues to expand in engineering practice. The direction of the rocket booster thrust line is directly related to the launch attitude and safety of the unmanned aerial vehicle, and is the core link in the assembly and debugging stage. The current mainstream thrust line measurement and adjustment methods mainly include two types: adjustment method based on gravity center measurement and suspension method. The former obtains the actual gravity center coordinates through the gravity center measurement platform, and then adjusts the gravity center to make the thrust line pass through the gravity center; the latter turns and hangs the unmanned aerial vehicle at the action point of the booster, measures the deviation of the thrust line by using the physical characteristics that the suspension rope or pull rod must pass through the gravity center, and adjusts the action direction of the booster to make the deviation value meet the launch safety standard.

[0003] For single-rocket boost unmanned aerial vehicles, the above-mentioned thrust line calibration technology has formed a mature scheme, but for double-rocket boost configurations, it is necessary to ensure that the two thrust lines are symmetrically distributed and pass through the plane where the gravity center is located, in order to avoid the yawing moment caused by asymmetric thrust. For double-rocket boost configurations, the above-mentioned methods for thrust line calibration include the gravity center measurement-based trimming adjustment method and the direct suspension measurement method, both of which have certain defects: for the direct suspension measurement method, when the unmanned aerial vehicle is in a non-full fuel state or uses a flexible soft fuel tank, the fuel will sway, and the attitude of the unmanned aerial vehicle in the suspension method is inconsistent with the actual launch attitude, resulting in a significant deviation between the measured gravity center position of the thrust line and the gravity center position of the launch attitude, which greatly increases the risk of launch failure. At the same time, for medium and large unmanned aerial vehicles, the suspension operation itself has safety hazards, and under the double-rocket configuration, it is not possible to intuitively establish the spatial correspondence between the gravity center and the steel rope (pull rod) by the suspension method. For the gravity center measurement-based trimming method, this method is generally performed without the rocket, so the influence of rocket assembly and installation errors on the thrust line is not considered; in addition, this method needs to adjust the actual gravity center by adding counterweights, which not only increases the structure weight, but also is difficult to achieve effective counterweight installation due to the compact internal space of the unmanned aerial vehicle. Therefore, the existing technical solutions cannot directly achieve high-precision measurement and convenient adjustment of the thrust line of the double-rocket boost unmanned aerial vehicle with limited internal space.

[0004] Therefore, it is urgent to provide a dual-rocket boost unmanned aerial vehicle thrust line measurement adjustment device and method to solve the above problems. SUMMARY

[0005] In order to avoid the shortcomings of the prior art, the present application provides a dual-rocket boost unmanned aerial vehicle thrust line measurement adjustment device and method, which realizes high-precision measurement of the dual-rocket boost unmanned aerial vehicle thrust line and effective adjustment of the thrust line about the plane where the center of mass is located by designing the measurement adjustment device and establishing the measurement adjustment method. The flexible clamping design in the measurement adjustment device realizes small-batch trial measurement adjustment process suitable for various unmanned aerial vehicles. The problems of being unable to directly and accurately measure the dual-rocket boost unmanned aerial vehicle thrust line measurement direction and being unable to effectively adjust the actual center of mass of the unmanned aerial vehicle to be on the rocket symmetry plane by trimming are solved.

[0006] The technical scheme of the present application is: a dual-rocket boost unmanned aerial vehicle thrust line measurement adjustment device, comprising: a three-axis center of mass measurement device for measuring the center of mass of a to-be-measured unmanned aerial vehicle mounted thereon; a flexible clamping mechanism mounted on the three-axis center of mass measurement device for connecting the three-axis center of mass measurement device and the unmanned aerial vehicle and being capable of adjusting the mounting position of the unmanned aerial vehicle on the three-axis center of mass measurement device; two rocket booster dummy parts mounted on both sides of the to-be-measured unmanned aerial vehicle for simulating real rockets; a rocket mounting mechanism for adjustably connecting the rocket booster dummy parts and the to-be-measured unmanned aerial vehicle; and a laser tracker for measuring the target point coordinates of the three-axis center of mass measurement device and the cylindrical feature point coordinates of the rocket booster dummy parts on both sides of the unmanned aerial vehicle; the laser tracker and the three-axis center of mass measurement device are electrically connected for transmitting the measurement data to the three-axis center of mass measurement device for processing.

[0007] A further technical scheme of the present application is: the three-axis center of mass measurement device comprises: a device base; a device measurement table mounted on the device base, the device measurement table comprising a weighing platform and a tilting mechanism, wherein the weighing platform is liftably mounted on the device base, the tilting mechanism is mounted on the weighing platform, and the tilting mechanism is used to adjust the attitude of the to-be-measured unmanned aerial vehicle to be horizontal, left-inclined and right-inclined, and the attitude of the unmanned aerial vehicle is tilted about the heading direction of the unmanned aerial vehicle; the flexible clamping mechanism is mounted on the tilting mechanism; a plurality of pressure sensors mounted between the base and the weighing platform, the weight of the device measurement table and the object mounted thereon being obtained through the pressure sensors; an X-axis grating positioning mechanism mounted on the device base at the front end of the device measurement table, the grating positioning mechanism being used to determine the heading direction of the to-be-measured unmanned aerial vehicle; And a control system for controlling the lifting of the weighing platform for weighing, controlling the tilting mechanism for adjusting the posture, and processing the obtained weighing data in different postures; the control system is also used for obtaining and processing the data collected by the laser tracker.

[0008] A further technical solution of the present application is that the tilting mechanism comprises: A motor installed at the bottom of the weighing platform for providing tilting power for the tilting mechanism; A transmission assembly installed on the weighing platform for power transmission; And a tilting platform assembly slidingly supported on the weighing platform through a guide wheel mechanism, the tilting platform assembly comprising a support frame and a tilting platform horizontally fixed on the support frame, and the support frame being provided with an arc-shaped rack on one side; Wherein, the output end of the motor and the input end of the transmission assembly are in transmission connection, the output end of the transmission assembly and the arc-shaped rack are in tooth engagement, the arc-shaped rack is driven to tilt on the guide wheel mechanism through the motor, and the tilting platform is tilted; the flexible clamping mechanism is installed on the tilting platform.

[0009] A further technical solution of the present application is that the flexible clamping mechanism comprises: Two guide rails, which are arranged in parallel and aligned at both ends, are fixedly installed on the tilting platform, and the direction of the guide rails is along the heading of the unmanned aerial vehicle and the two guide rails are symmetrically installed along the center line of the tilting platform; Four sliding blocks, two sliding blocks in a group are slidingly installed on one guide rail; Two clamping base plates, which are arranged in parallel, are fixedly connected with the sliding blocks on both ends of the clamping base plates corresponding to the two guide rails; a center line is marked on the clamping base plate along the heading, and the center line is used for identifying the center line of the flexible clamping mechanism; And four quick-change clamps, two in a group, are installed on the clamping base plate, and the quick-change clamp is used for connecting the unmanned aerial vehicle to be tested.

[0010] A further technical solution of the present application is that a plurality of threaded holes are arranged in a matrix on the clamping base plate for mounting different types of quick-change clamps; the quick-change clamp is designed according to different specifications of the unmanned aerial vehicle, and is a frame plate structure, the bottom plate of the quick-change clamp is fixedly connected with the clamping base plate through a fastener, and the top plate of the quick-change clamp is connected with the support block of the unmanned aerial vehicle, a strip-shaped hole is arranged on the top plate, and the mounting axial direction of the unmanned aerial vehicle is adjusted by adjusting the position of the fastener in the strip-shaped hole.

[0011] A further technical solution of the present application is that the rocket mounting mechanism comprises an adjusting mounting seat and a mounting frame body, the adjusting mounting seat is fixedly installed on the unmanned aerial vehicle, and the mounting frame body is connected with the rocket booster dummy and the adjusting mounting seat.

[0012] The further technical scheme of the present application is: the adjusting mounting base comprises a connecting base and a pressing block, the connecting base is fixedly connected with the unmanned aerial vehicle body, and the pressing block is adjustably connected with the connecting base; the adjusting direction of the pressing block relative to the connecting base is vertical to the horizontal plane, i.e. up-down adjustment.

[0013] A thrust line measurement and adjustment method for a double-rocket-assisted unmanned aerial vehicle, which adopts a double-rocket-assisted unmanned aerial vehicle thrust line measurement and adjustment device, comprises the following steps: Step 1. Install the flexible clamping mechanism on the three-axis centroid measurement equipment, start the three-axis centroid measurement equipment, and measure the empty skin weight of the equipment measurement table in the horizontal, left tilt and right tilt attitudes after the flexible clamping mechanism is installed; the control system calculates the centroid coordinates of the equipment measurement table in the empty state according to the measurement data, and determines the measurement equipment tool coordinate system; Step 2. Install the rocket booster dummy on both sides of the unmanned aerial vehicle using the rocket installation mechanism, then place the unmanned aerial vehicle on the flexible clamping mechanism, and make the center line of the unmanned aerial vehicle coincide with the center line of the flexible clamping mechanism, and then fixedly connect the unmanned aerial vehicle and the flexible clamping mechanism; Step 3. Start the three-axis centroid measurement equipment, and measure the total weight of the unmanned aerial vehicle in the horizontal, left tilt and right tilt attitudes after the equipment measurement table is loaded with the unmanned aerial vehicle; the control system calculates the centroid spatial coordinates of the unmanned aerial vehicle in the measurement equipment tool coordinate system according to the total weight of the unmanned aerial vehicle and the empty skin weight of the equipment measurement table; Step 4. Measure the target point coordinates on the three-axis centroid measurement equipment using a laser tracker, and transfer them to the control system; create a space reference surface by the measurement software built in the control system, obtain a laser coordinate system, align the laser coordinate system and the measurement equipment tool coordinate system by the control system, establish a unified coordinate, and form a measurement coordinate system; Step 5. Collect the feature points of the cylindrical surface of the rocket booster dummy on both sides using the laser tracker, and obtain the feature point coordinates of the surface of the rocket booster dummy by the control system, and calculate and process to generate the axes of the rocket booster dummy on both sides, i.e. obtain the thrust line direction in the current installation state of the rocket booster dummy; Step 6. The control system creates the centroid point of the unmanned aerial vehicle in the measurement coordinate system according to the centroid spatial coordinates of the unmanned aerial vehicle in the measurement equipment tool coordinate system, and calculates the deviation values of the axes of the rocket booster dummy on both sides and the centroid, including the pitch angle deviation of the axes of the rocket booster dummy on both sides and the horizontal plane where the centroid is located, and the inner angle deviation of the axes of the rocket booster dummy on both sides and the vertical plane where the centroid is located; Step 7. Adjust the installation position and attitude of the rocket booster dummy through the rocket installation mechanism according to the pitch angle deviation and the inner angle deviation, and then adjust the axes of the rocket booster dummy on both sides; after adjustment, repeat steps 5 and 6 for verification until the pitch angle deviation and the inner angle deviation meet the design requirements; Thus, the final double-rocket boost unmanned aerial vehicle thrust line direction is obtained.

[0014] A further technical solution of the present application is that the method for adjusting the installation posture of the rocket booster dummy in step 7 comprises that the pitch angle deviation is adjusted by moving the pressing block up and down, and the yaw angle deviation is adjusted by adding a gasket between the connecting base and the unmanned aerial vehicle body.

[0015] A further technical solution of the present application is that the origin of the measurement coordinate system is the center of the equipment measurement table, the X axis is forward along the flight direction of the unmanned aerial vehicle, the Z axis is upward perpendicular to the horizontal plane, and the Y axis is perpendicular to the symmetry plane of the unmanned aerial vehicle body, in line with the right-hand rule.

[0016] The present application has the beneficial effects that the double-rocket boost unmanned aerial vehicle thrust line measurement adjustment device integrates a three-axis centroid measurement device, a laser tracker, a flexible clamping mechanism, a rocket installation mechanism and a rocket booster dummy to form a closed-loop high-precision measurement adjustment system, and realizes quantitative control of the symmetry of the two-side thrust lines relative to the centroid of the unmanned aerial vehicle and the coplanarity of the plane where the two-side thrust lines are located and the centroid of the unmanned aerial vehicle under the condition of no counterweight. The device takes the tooling coordinate system of the centroid measurement device as the unified reference, uses the laser tracker to perform discrete point cloud scanning and axis fitting on the cylindrical surface of the rocket dummy, decomposes the thrust line direction error into pitch angle and yaw angle, and realizes installation compensation through the adjusting mechanism of the rocket adjusting and installation clamp, thereby avoiding the system error caused by fuel drift in the traditional suspension method. At the same time, the flexible clamping mechanism is compatible with multiple types of unmanned aerial vehicles, can be quickly changed, and significantly shortens the trial production period. The centroid-thrust line joint calculation algorithm in the given measurement adjustment method directly outputs the adjustment amount, reduces the number of iterations, improves the one-time assembly qualification rate of the rocket, and meets the safety requirements of rocket boost launch while being convenient to read and operate.

[0017] The present application avoids measuring and adjusting the double-rocket boost unmanned aerial vehicle thrust line by using the existing traditional method, solves the problem that the direct suspension measurement method cannot directly measure the double-rocket boost unmanned aerial vehicle thrust line with high precision, and solves the problem that the trimming adjustment method based on the gravity center measurement cannot effectively make the actual centroid of the unmanned aerial vehicle located on the rocket symmetry plane, and the internal limited space of the unmanned aerial vehicle is difficult to realize effective counterweight installation. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating any inventive labor.

[0019] Figure 1A double-rocket-assisted unmanned aerial vehicle thrust line measurement adjustment device overall structure schematic diagram of the present application; Figure 2 A flexible clamping mechanism structure schematic diagram of the present application; Figure 3 A device measurement table structure diagram of the three-axis centroid measurement equipment of the present application; Figure 4 A partial schematic diagram of the tilting mechanism installed on the weighing platform of the present application; Figure 5 A partial enlarged view of the protruding support block of the quick-change clamp installed unmanned aerial vehicle of the present application; Figure 6 A structure schematic diagram of the rocket installation mechanism installing rocket booster dummy of the present application; Figure 7 A first adjustment mounting seat structure diagram of the rocket installation mechanism of the present application; Figure 8 A double-rocket-assisted unmanned aerial vehicle thrust line measurement adjustment flowchart of the present application.

[0020] In the figure: 1. Device base, 2. Flexible clamping mechanism, 2-1. Guide rail, 2-2. Clamping base plate, 2-2-1. Reticle, 2-3. Quick-change clamp, 2-3-1. Bottom plate, 2-3-2. Vertical plate, 2-3-3. Top plate, 2-3-4. Pressing plate, 3. Tilting mechanism, 3-1. Motor, 3-2. Transmission assembly, 3-2-1. Bracket, 3-2-2. Transmission shaft, 3-2-3. Sprocket, 3-2-4. Pinion, 3-3. Support frame, 3-3-1. Reinforcing plate, 3-3-2. Connecting rod, 3-4. Tilting platform, 3-5. Arc-shaped rack, 3-6. Guide wheel mechanism, 3-7. Limiting plate, 4. Weighing platform, 5. Measurement equipment cable, 6. Control system, 7. Laser tracker cable, 8. Laser tracker, 9. Rocket installation mechanism, 9-1. First adjustment mounting seat, 9-1-1. Connecting base, 9-1-2. Pressing block, 9-1-21. Strip-shaped hole, 9-1-22. Pin hole, 9-1-23. Ball socket, 9-2. Mounting frame body, 9-3. Second adjustment mounting seat, 10. Rocket booster dummy, 11. X-axis grating positioning mechanism, 12. Unmanned aerial vehicle, 13. Support block. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0022] Example 1: The embodiment provides a double-rocket-assisted unmanned aerial vehicle thrust line measurement adjusting device. Figure 1 As shown in the figure, the whole device comprises a three-axis centroid measurement device, a flexible clamping mechanism 2, two rocket booster dummy parts 10, a rocket mounting mechanism 9 and a laser tracker 8, and the device is a double-thrust line calibration device without counterweight, direct measurement mode and reliable precision.

[0023] The three-axis centroid measurement device is used for measuring the centroid of the unmanned aerial vehicle carried thereon, and the structure comprises a device base 1, a device measurement table, a pressure sensor, an X-axis grating positioning mechanism 11 and a control system 6.

[0024] The device base 1 is a steel frame structure, a cast iron platform is welded on the device base 1, and a reinforced aluminum alloy skin is installed outside, and the surface flatness of all the installation platforms on the base 1 is ≤0.1mm.

[0025] As shown in the figure, Figure 1 , Figure 3 The device measurement table, as an actuator of the three-axis centroid measurement device, comprises a weighing platform 4 and a tilting mechanism 3, and the device measurement table is integrally and liftable installed on the device base 1, the weighing platform 4 is connected with the inner bottom frame platform of the device base 1 through three-point support, a high-precision pressure sensor is arranged at each support point of the three-point support, the pressure sensor is installed between the inner bottom frame platform of the device base 1 and the weighing platform 4, when the weighing platform 4 falls on the pressure sensor, the weight of the device measurement table and the object installed thereon can be obtained through the pressure sensor. The projection of the symmetric axis of the three-point support and the center line of the weighing platform 4 on the horizontal plane coincides, so as to ensure the measurement accuracy. The pressure sensor is electrically connected with the control system 6 through a measurement device cable 5, the measurement device cable 5 is used for supplying power to the pressure sensor and transmitting the pressure sensor measurement signal to the control system 6. The range of the pressure sensor is 0-1000kg, and the accuracy is 0.01%.

[0026] The tilting mechanism 3 is installed on the weighing platform 4, and the tilting mechanism 3 is used for adjusting the attitude of the unmanned aerial vehicle 12 to be measured to be horizontal, left inclined and right inclined, the attitude of the unmanned aerial vehicle 12 is tilted around the heading direction of the unmanned aerial vehicle, and then the weight data under different attitudes is measured through the pressure sensor, based on the multi-sensor value and the moment balance principle, combined with the multi-attitude moment balance equation, the spatial coordinates of the three-axis centroid of the unmanned aerial vehicle in the measurement device tool coordinate system are solved. The control system 6 is responsible for controlling the tilting mechanism to move, and completes the weight data acquisition and analysis solution.

[0027] The tilting mechanism 3 specifically includes a servo motor 3-1, a transmission assembly 3-2, and a tilting platform assembly. The motor 3-1 is mounted on the bottom of the weighing platform 4 to provide tilting power to the tilting mechanism 3. The transmission assembly 3-2 is mounted on the weighing platform 4 to connect the motor 3-1 and the tilting platform assembly, enabling power transmission. The tilting platform assembly is slidably supported on the weighing platform 4 by four sets of guide wheel mechanisms 3-6, and is also limited by the limiting plate 3-7 in the UAV's heading and the height direction of the gear meshing transmission.

[0028] The tilting platform assembly includes a support frame 3-3 and a tilting platform 3-4 horizontally fixed to the support frame 3-3. An arc-shaped rack 3-5 is fixedly mounted on one side of the support frame 3-3, and the arc-shaped rack 3-5 is used to connect with the transmission assembly 3-2. The output end of the motor 3-1 is connected to the input end of the transmission assembly 3-2, and the output end of the transmission assembly 3-2 meshes with the arc-shaped rack 3-5. The motor 3-1 drives the arc-shaped rack 3-5 to tilt on the guide wheel mechanism 3-6, thereby tilting the tilting platform 3-4. The motor 3-1 is controlled by the control system 6.

[0029] Specifically, the support frame 3-3 is a frame structure, including four coaxially arranged arc-shaped reinforcing plates 3-3-1. Each reinforcing plate 3-3-1 is connected by two connecting rods 3-3-2 to form the support frame. The tilting platform 3-4 is horizontally fixedly installed on the arc-shaped inner ring of each reinforcing plate 3-3-1, and the arc-shaped outer ring of the two end reinforcing plates 3-3-1 is slidably supported by the guide wheel mechanism 3-6. The guide wheel mechanism 3-6 includes a guide wheel support installed on the weighing platform 4 and a guide wheel rotatably installed on the guide wheel support. The guide wheel provides support for the two end reinforcing plates 3-3-1 and guides them during tilting. An arc-shaped rack 3-5 is installed on the outer side of one end reinforcing plate 3-3-1.

[0030] like Figure 4 As shown, the transmission assembly 3-2 includes a transmission support 3-2-1, a transmission shaft 3-2-2, a sprocket 3-2-3, and a pinion 3-2-4. The transmission support 3-2-1 is mounted on the weighing platform 4. The transmission shaft 3-2-2 is rotatably mounted on the transmission support 3-2-1. The sprocket 3-2-3 is mounted on one end of the transmission shaft 3-2-2, and the pinion 3-2-4 is mounted on the other end of the transmission shaft 3-2-2. The output end of the motor 3-1 is connected to the sprocket 3-2-3 via a chain, driving the transmission shaft 3-2-2 to rotate, which in turn drives the pinion 3-2-4 to rotate. The pinion meshes with the arc-shaped rack 3-5, thereby causing the tilting platform assembly to tilt, enabling the tilting platform 3-4 to tilt left and right around the UAV's heading. In this embodiment, the tilting angle range of the tilting platform assembly is ±45°, and the tilt resolution is 0.01°.

[0031] The flexible clamping mechanism 2 is installed on the tilting platform 3-4, and is connected to the unmanned aerial vehicle 12 and the tilting platform 3-4, so as to realize tilting of the unmanned aerial vehicle 12. The flexible clamping mechanism 2 is suitable for unmanned aerial vehicles of different specifications and can adjust the installation position of the unmanned aerial vehicle.

[0032] As shown in Figure 2 The flexible clamping mechanism 2 includes two guide rails 2-1, four sliding blocks, two clamping base plates 2-2 and four quick-change clamps 2-3. The guide rail 2-1 is a T-shaped groove structure, and the two guide rails 2-1 are arranged in parallel and aligned at both ends, and are fixedly installed on the tilting platform 3-4 through mechanical connection. The direction of the guide rail 2-1 is along the heading direction of the unmanned aerial vehicle, and the two guide rails are symmetrically installed along the center line of the tilting platform 3-4. One group of two sliding blocks is slidingly installed on one guide rail 2-1. The clamping base plate 2-2 is made of stainless steel plate, and the two clamping base plates 2-2 are arranged in parallel and vertically arranged on the sliding blocks of the two guide rails 2-1, and are fixedly connected with the sliding blocks through a plurality of bolts, so that the two clamping base plates 2-2 can slide along the guide rail 2-1. A one-line reference line 2-2-1 is arranged at the center position of the clamping base plate 2-2 along the heading direction, and the reference line 2-2-1 is used to identify the center line of the flexible clamping mechanism, and is located at the center position of the two guide rails 2-1. The reference line 2-2-1 is used to align with the center axis of the unmanned aerial vehicle 12 when the unmanned aerial vehicle 12 is installed. The quick-change clamp 2-3 is installed on the clamping base plate 2-2, and four quick-change clamps 2-3 are arranged in two groups, and each group is installed at both ends of one clamping base plate 2-2. The four quick-change clamps 2-3 are respectively supported at the four corner positions of the flexible clamping mechanism 2, and are used to correspondingly connect with the four supporting blocks 13 of the unmanned aerial vehicle to be tested.

[0033] Specifically, a plurality of threaded holes (with a pitch of 50mm*50mm) are arranged in a matrix array on the clamping base plate 2-2, which are used for installation of quick-change clamps 2-3 of different models. The quick-change clamps 2-3 are designed according to unmanned aerial vehicles of different specifications, and the connection end of the unmanned aerial vehicle can be positioned in multiple ways, such as multiple face positioning, two-hole positioning, and the like. In this embodiment, the quick-change clamp 2-3 is a frame plate structure made of aluminum alloy, which includes a bottom plate 2-3-1, a vertical plate 2-3-2, a top plate 2-3-3 and a pressing plate 2-3-4. The bottom plate 2-3-1 is fixedly connected with the clamping base plate 2-2 through a plurality of bolts, and the vertical plate 2-3-2 supports and connects the bottom plate 2-3-1 and the top plate 2-3-3. The pressing plate 2-3-4 is installed on the top plate 2-3-3 of one group of quick-change clamps 2-3 located at the rear end, and the supporting block 13 of the unmanned aerial vehicle is pressed by the pressing plate 2-3-4. The top plate 2-3-3 of the other group of quick-change clamps 2-3 located at the front end is directly and threadedly fixedly connected with the supporting block 13 of the unmanned aerial vehicle. Figure 2 and Figure 5The end surface of the pressing plate 2-3-4 facing the top plate 2-3-3 is provided with a slot hole for inserting the support block 13 of the unmanned aerial vehicle, and the pressing plate 2-3-4 and the corresponding top plate 2-3-3 are provided with corresponding strip-shaped holes. By adjusting the position of the fastener in the strip-shaped hole, the axial position of the unmanned aerial vehicle is adjusted. The design of the quick-change clamp 2-3 strip-shaped hole realizes the spanwise adjustment (perpendicular to the heading and Y-axis direction) of the unmanned aerial vehicle during clamping. By moving the slider on the guide rail 2-1, the forward and backward adjustment along the heading is realized to ensure that the symmetry line on the front and rear frames of the unmanned aerial vehicle is aligned with the reticle 2-2-1 on the front and rear clamping base plate 2-2, avoiding the measurement error caused by clamping error.

[0034] Two rocket booster dummy parts 10 are installed on both sides of the unmanned aerial vehicle 12 to be measured through the rocket mounting mechanism 9. The rocket booster dummy part 10 is used to simulate the real rocket, which is consistent with the size, installation mechanical interface and weight of the real rocket, and is used to replace the real rocket for measurement.

[0035] The rocket mounting mechanism 9 can adjust the connection between the rocket booster dummy part 10 and the unmanned aerial vehicle 12 to be measured. As shown in Figure 6 、 Figure 7 , the rocket mounting mechanism 9 includes three adjustment mounting seats and an installation frame body 9-2. The adjustment mounting seat is fixedly installed on the unmanned aerial vehicle 12, and the installation frame body 9-2 connects the rocket booster dummy part 10 and the adjustment mounting seat. In the embodiment, the adjustment mounting seat includes a first adjustment mounting seat 9-1 located at the front end of the rocket and two second adjustment mounting seats 9-3. The installation frame body 9-2 connects the rocket booster dummy part 10 and the two second adjustment mounting seats 9-3. The main body of the installation frame body 9-2 is a welded steel structure, one end of which is inserted and connected with the corresponding four single lugs of the rocket booster dummy part 10 through four double lugs. The double lugs and the single lugs are provided with a φ5H7 positioning pin hole corresponding to each other, which is used to pass through and fix the positioning pin. The other end of the installation frame body 9-2 is fixedly connected with the two second adjustment mounting seats 9-3 through two φ5 positioning pins. The first adjustment mounting seat 9-1 is connected with the ball head at the front end of the rocket booster dummy part 10.

[0036] The adjusting mount comprises a connecting base and a pressing block. The connecting base is made of high-strength steel and is connected and fixed with the embedded nut of the UAV body through four M5 high-strength bolts to realize the fixed connection with the body. The pressing block is adjustably connected with the connecting base, and the adjusting direction of the pressing block relative to the connecting base is the up-down adjustment perpendicular to the horizontal plane. The connecting base structures of the first adjusting mount 9-1 and the second adjusting mount 9-3 are the same, and the adjustable connection modes of the pressing blocks of the two adjusting mounts and the connecting bases thereof are the same. Only the end of the pressing block opposite to the connecting base is designed with a corresponding structure to adapt to the ball head of the front end of the mounting rack body 9-2 or the rocket booster dummy 10. The second adjusting mount 9-3 and the pressing block are fixed by pin connection, and the second adjusting mount 9-3 and the pressing block are provided with a pin hole with a diameter of φ5 for positioning the pin.

[0037] Specifically see Figure 7 The adjusting connection mode of the connecting base and the pressing block is introduced by taking the first adjusting mount 9-1 as an example. The first adjusting mount 9-1 comprises a connecting base 9-1-1 and a pressing block 9-1-2. The connecting base 9-1-1 is provided with a U-shaped groove 9-1-11. The pressing block 9-1-2 is provided with a protruding part and is slidably matched with the U-shaped groove 9-1-11 to adjust the position of the pressing block 9-1-2 relative to the connecting base 9-1-1. The pressing block 9-1-2 is provided with a strip-shaped hole 9-1-21. Two threaded holes are arranged on the connecting base 9-1-1 corresponding to the strip-shaped hole 9-1-21. Two M5 high-strength bolts are sequentially inserted through the strip-shaped hole 9-1-21 of the pressing block and the threaded hole of the connecting base 9-1-1 to pre-connect. The strip-shaped hole 9-1-21 and the U-shaped groove 9-1-11 are used to adjust the position of the pressing block 9-1-2. Meanwhile, the pressing block 9-1-2 is also provided with two pin holes 9-1-22 with a diameter of φ5. When the position of the pressing block 9-1-2 relative to the connecting base 9-1-1 is adjusted in place, the pin holes 9-1-22 are matched with the pin holes with a diameter of φ5 on the connecting base 9-1-1. The position of the pressing block 9-1-2 and the connecting base 9-1-1 is positioned by inserting the positioning pin, and then the two M5 high-strength bolts are fastened.

[0038] When the connecting base is fixedly mounted with the body, the U-shaped groove is perpendicular to the horizontal plane. By adjusting the mounting position of the pressing block relative to the connecting base, the pitch angle of the rocket booster dummy 10 axis can be changed. By adding a gasket between the connecting base and the body of the UAV 12, the included angle between the rocket booster dummy 10 axis and the heading of the UAV can be adjusted.

[0039] The X-axis grating positioning mechanism 11 is installed on the equipment base 1 and located at the front end of the equipment measuring table. The grating positioning mechanism 11 is used to determine the heading direction of the unmanned aerial vehicle 12. The X-axis grating positioning mechanism 11 includes a linear guide rail, a ruler and a digital display ruler. The guide rail of the grating positioning mechanism 11 is installed on the equipment base 1. The ruler can move along the guide rail, and the movable range is 0-1500 mm, and the positioning accuracy is 0.02 mm. By contacting the ruler with the vertex of the head of the unmanned aerial vehicle 12, the reading on the digital display ruler is read, the deviation of the unmanned aerial vehicle coordinate system and the equipment measuring table coordinate system in the heading direction of the unmanned aerial vehicle is measured, and the zero point compensation of the coordinate system in the heading direction of the unmanned aerial vehicle is used.

[0040] The laser tracker 8 is used to measure the target point coordinates of the three-axis centroid measurement device and the cylindrical feature point coordinates of the rocket booster dummy 10 on both sides of the unmanned aerial vehicle, and then the axis of the rocket booster dummy 10 is fitted through the feature points to determine the thrust line direction. In this embodiment, the laser tracker 8 is a mature high-precision spatial continuous measurement device, specifically Leica AT960, with a measurement accuracy of 0.001 mm. Relying on laser tracking technology combined with commercial measurement software PolyWorks, the above data is acquired and recorded to realize high-precision real-time measurement of spatial coordinates.

[0041] The control system 6 is the comprehensive control core of the entire three-axis centroid measurement device, which is used to control the operation of the equipment measuring table, including controlling the lifting of the weighing platform 4 for weighing, controlling the attitude adjustment of the tilting mechanism 3, and processing the weighing data obtained in different attitudes. The control system 6 is also connected with the laser tracker through the laser tracker cable 7 for acquiring and processing the data collected by the laser tracker 8. In this embodiment, the control system 6 adopts an industrial computer to control the tilting angle through a closed-loop PID algorithm to ensure that the attitude accuracy meets the accuracy requirements. Meanwhile, the centroid solving software is built-in to solve the three-axis centroid data by collecting the mass data measured by the pressure sensor in three attitudes (horizontal, left tilt 30° and right tilt 30°) and combining the moment balance equation. The commercial measurement software PolyWorks is built-in the control system 6 to process the data collected by the laser tracker 8.

[0042] Embodiment 2: The embodiment provides a method for measuring and adjusting the thrust line of a dual-rocket-boosted unmanned aerial vehicle. The method is based on the device described in embodiment 1 and includes the following steps: Step 1. Measure the tare weight of the equipment measuring table to determine the measurement device tool coordinate system.

[0043] The flexible clamping mechanism 2 is installed on the three-axis centroid measurement device, the three-axis centroid measurement device is started to work, and the empty dead weight of the device measuring table in the horizontal, left tilt and right tilt three postures after the flexible clamping mechanism 2 is installed is measured in turn. The control system 6 calculates the centroid coordinates of the device measuring table in the empty state according to the measurement data, and determines the measuring device tool coordinate system.

[0044] Specifically, the flexible clamping mechanism 2 is symmetrically installed on the tilting platform 3-4 of the three-axis centroid measurement device on both sides, and the center symmetry plane of the guide rail 2-1 is coincided with the center line of the device measuring table. The automatic measurement program of the three-axis centroid measurement device is started by the control system 6, and the tilting mechanism 3 performs the following actions in turn: (1) The tilting platform 3-4 is reset to the horizontal position (0°±0.01°), and the sensor data is recorded after being kept stable for 30 seconds, (2) The tilting platform 3-4 is tilted to the left by 30° (+30°±0.01°), and the data is recorded after being kept stable for 30 seconds to eliminate the inertia effect; (3) The tilting platform 3-4 is returned to the horizontal position and tilted to the right by 30° (-30°±0.01°), and the data is recorded after being kept stable for 30 seconds.

[0045] The data of the pressure sensor is collected and recorded by the control system 6, and when the measurement of the three postures is completed, the control system 6 calculates the dead weight centroid coordinates of the device measuring table and the flexible clamping mechanism 2 in the empty state according to the moment balance equation, which is used as the reference value for subsequent measurement, and the measuring device tool coordinate system is determined.

[0046] Step 2. Rocket booster dummy 10 installation and unmanned aerial vehicle 12 clamping.

[0047] Two rocket booster dummies 10 are symmetrically installed on both sides of the unmanned aerial vehicle 12 to be measured using the rocket installation mechanism 9, and then the unmanned aerial vehicle 12 is placed on the flexible clamping mechanism 2, and the axial center line of the unmanned aerial vehicle 12 is aligned and coincided with the center line of the flexible clamping mechanism 2, and then the unmanned aerial vehicle 12 and the flexible clamping mechanism 2 are fixedly connected.

[0048] Specifically, the pressing block of the rocket installation mechanism 9 is pre-installed in the middle position of the connecting base, and the connecting base is fixed to the preset initial installation position on the machine body by M5 bolts. The rocket booster dummy 10 is installed to the installation frame body 9-2, and the installation frame body 9-2 and the rocket booster dummy 10 are connected by positioning pins, and the installation frame body 9-2 and the pressing blocks of the two second connecting bases are also connected by positioning pins. The protruding ball head at the front end of the rocket booster dummy 10 is in adaptive contact with the ball socket 9-1-23 on the first pressing block 9-1-2 of the first adjustment mounting seat 9-1. The unmanned aerial vehicle 12 is hoisted to the flexible clamping mechanism 2 using hoisting equipment, and the symmetry axis of the unmanned aerial vehicle 12 (i.e. the symmetry line on the front and rear frames of the unmanned aerial vehicle) is adjusted to be in line with the symmetry axis of the clamping base plate 2-2 (i.e. the one-character reference line of the clamping base plate 2-2).Figure 2 The mark lines are overlapped, and the error of the overlapping is less than or equal to 0.2 mm to eliminate the clamping error. The unmanned aerial vehicle 12 is fixed by the quick-change fixture 2-3. Specifically, the two support blocks 13 at the front end of the unmanned aerial vehicle 12 are fixed by screwing with the top plates 2-3-3 of the corresponding two quick-change fixtures 2-3, and the two support blocks 13 at the rear end of the unmanned aerial vehicle 12 are inserted into the slot holes of the pressing plates 2-3-4, and then the pressing plates 2-3-4 and the corresponding top plates 2-3-3 are fixed by bolt connection. The unmanned aerial vehicle 12 is clamped, and the clamping force is uniformly distributed to ensure that the attitude of the unmanned aerial vehicle meets the measurement requirements.

[0049] Step 3. Centroid measurement of the unmanned aerial vehicle 12.

[0050] The three-axis centroid measurement device is started to work, and the total weight of the unmanned aerial vehicle 12 in the horizontal, left tilt and right tilt attitudes is measured in sequence. The control system 6 calculates the centroid spatial coordinates of the unmanned aerial vehicle in the measurement device tool coordinate system according to the total weight of the unmanned aerial vehicle 12 and the tare weight of the empty measurement device table.

[0051] Specifically, the X-axis grating positioning mechanism 11 is moved to the vertex of the nose of the unmanned aerial vehicle 12, and the current X-axis coordinate is recorded by the digital display ruler and set as the zero point of the measurement coordinate system. The tilt mechanism 3 is controlled to be adjusted to the horizontal, left tilt 30° and right tilt 30° attitudes in sequence, and the pressure sensor data is collected after being kept stable for 30 seconds in each attitude. The control system 6 uses the built-in centroid calculation software to calculate the three-axis centroid coordinates based on the weight values measured by the pressure sensor in each attitude. The X and Y axis centroids are calculated based on the moment balance equation in the horizontal attitude, and the Z axis centroid is calculated based on the two tilt attitudes. The left and right tilt is repeated twice to improve the accuracy of the Z axis calculation. The tare weight reference value is removed, and the centroid spatial coordinates (Xc, Yc, Zc) of the unmanned aerial vehicle centroid in the measurement device tool coordinate system are output. During the centroid measurement, the measurement is repeated three times to take the average value, and the error of the three repeated measurements is less than or equal to 0.2 mm.

[0052] Step 4. Coordinate alignment and establishment of measurement coordinate system.

[0053] The target point coordinates on the three-axis centroid measurement device are measured by the laser tracker 8 and transmitted to the control system 6. A space reference surface is created by the control system 6 to obtain a laser coordinate system. The control system 6 aligns the laser coordinate system and the measurement device tool coordinate system to establish a unified coordinate and form a measurement coordinate system.

[0054] Specifically, three mutually perpendicular planes on the base 1 of the triaxial centroid measurement device are selected, and more than four target point coordinates on each plane are measured randomly by using the laser tracker 8 to create three reference planes and obtain the laser tracker coordinate system. The laser tracker coordinate system is aligned with the tooling coordinate system of the centroid measurement device by selecting the three reference planes to align the features, and the alignment error is less than or equal to 0.05 mm. A unified reference coordinate system, i.e., a measurement coordinate system, is defined, with the origin at the center of the device measurement table, the X-axis along the forward direction of the flight direction of the unmanned aerial vehicle, the Z-axis perpendicular to the horizontal plane upward, and the Y-axis perpendicular to the symmetry plane of the unmanned aerial vehicle body, in accordance with the right-hand rule.

[0055] Step 5. Rocket axis measurement and fitting.

[0056] The feature points of the cylindrical surface of the two-sided rocket booster dummy 10 are collected by using the laser tracker 8, the control system 6 acquires the surface feature point coordinates of the two-sided rocket booster dummy 10, and calculates and processes to generate the axes of the two-sided rocket booster dummy 10, i.e., to obtain the direction of the thrust line in the current installation state of the rocket booster dummy 10.

[0057] Specifically, the cylindrical surface of the two-sided rocket booster dummy 10 is scanned non-contact by using the laser tracker 8: more than 15 discrete point cloud data are collected on each side, covering the full circumference and axial length of the cylindrical surface by more than 80%. The point cloud data is fitted to a cylindrical surface by using the PolyWorks software, and the cylindrical surface axis is automatically extracted and defined to obtain the current direction vector (L1, L2) of the two-sided rocket dummy 10 in the unified coordinate system.

[0058] Step 6. Deviation calculation.

[0059] The control system 6 creates a centroid point of the unmanned aerial vehicle in the measurement coordinate system according to the centroid spatial coordinates of the unmanned aerial vehicle in the measurement device tooling coordinate system, and calculates the deviation value of the axes of the two-sided rocket booster dummy from the centroid, including the pitch angle deviation of the axes of the two-sided rocket booster dummy and the horizontal plane on which the centroid is located, and the inner angle deviation of the axes of the two-sided rocket booster dummy and the vertical plane on which the centroid is located.

[0060] Specifically, the centroid coordinates (Xc, Yc, Zc) of the unmanned aerial vehicle are imported into the measurement coordinate system to create a centroid point C, and the pitch angle θ deviation and the inner angle φ deviation of the axes of the two-sided rocket booster dummy 10 from the plane on which the centroid is located are calculated. (1) Pitch angle deviation The pitch angle deviation is measured by using the PolyWorks software to measure the angle between the projection of the axes of the two-sided rocket booster dummy 10 on the XOZ plane and the horizontal plane (XOY plane), and the calculation formula is:

[0061] wherein (x1, y1) and (x2, y2) are two points on the axis L1 of the left rocket booster mockup 10, , and (x3, y3) and (x4, y4) are two points on the axis L2 of the right rocket booster mockup 10; the pitch angle deviation of the two rockets is required to satisfy , . Similarly, the pitch angle deviation of the two rockets is calculated as :

[0062] wherein (x1, y1) and (x2, y2) are two points on the axis L1 of the left rocket booster mockup 10, , and (x3, y3) and (x4, y4) are two points on the axis L2 of the right rocket booster mockup 10; the pitch angle deviation of the two rockets is required to satisfy , . -

[0063] (2) Inward angle deviation : the angle between the projection of the axis of the two rocket booster mockups 10 in the horizontal plane (XOY plane) and the X axis is measured by PolyWorks software, and the calculation formula is:

[0064] wherein (x1, y1) and (x2, y2) are two points on the axis L1 of the left rocket booster mockup 10, , and (x3, y3) and (x4, y4) are two points on the axis L2 of the right rocket booster mockup 10, , . Similarly, the pitch angle deviation of the two rockets is calculated as :

[0065] wherein (x1, y1) and (x2, y2) are two points on the axis L1 of the left rocket booster mockup 10, , and (x3, y3) and (x4, y4) are two points on the axis L2 of the right rocket booster mockup 10; the pitch angle deviation of the two rockets is required to satisfy , . -

[0066] (3) Axis intersection plane deviation ΔY: the plane where the centroid is located is the symmetry plane (XcOZc plane, Y=Yc), and the Y coordinate of the intersection point of the axes of the two rocket booster mockups 10 is required to satisfy: ΔY=|Yi-Yc|≤0.5mm For the double rocket booster, the intersection point of the two rocket axes is required to pass through the plane where the centroid is located, without being required to coincide with the centroid coordinate. That is, the Y axis coordinate Yi of the axis intersection point must be located in the plane where the centroid is located, with a deviation of ≤0.5mm.

[0067] Step 7. Thrust line adjustment.​​

[0068] Based on the elevation angle deviation and flare angle deviation, the installation position and attitude of the rocket booster dummy 10 are adjusted via the rocket mounting mechanism 9, thereby adjusting the axes of the two rocket booster dummy 10s. After adjustment, steps 5 and 6 are repeated for verification until the elevation angle deviation and flare angle deviation of the rocket thrust lines on both sides meet the design requirements, making the rocket thrust lines on both sides symmetrical and their intersection point pass through the plane containing the center of mass. The elevation angle deviation is adjusted by moving the pressure block up and down, and the flare angle deviation is adjusted by adding shims between the connecting base and the UAV fuselage.

[0069] Specifically, based on the deviation calculation in step 6 and the launch safety requirements for the rocket's axial symmetry, the thrust line deviation is adjusted as follows: (1) Pitch angle adjustment: like > Adjust the mounting bracket connected to the dummy rocket booster 10 on the left side to move the pressure block downward along the U-shaped guide groove, thereby reducing the height of the left rocket; conversely, adjust the right side.

[0070] The adjustment amount is Δh = Lxoz•sin(∣ - |), where Lxoz is the projected length of the rocket in the XOZ plane. After adjustment, remeasure the pitch angle until | - |≤0.1°.

[0071] (2) Adjustment of the inner corner: like > Adjust the mounting bracket on the rear side of the right rocket booster dummy 10, and add a stainless steel shim (0.1mm thick) between the connecting base and the fuselage to increase the outward flare angle of the right rocket; conversely, adjust the left side.

[0072] The adjustment amount is Δt = Lxoy•sin(∣ - |), where Lxoy is the projected length of the rocket in the XOY plane. After each adjustment, the axis is refitted to verify the deviation of the inner slash angle, until | - |≤0.1°.

[0073] (3) Adjustment of the coordinates of the intersection of the axes: If ΔY > 0.5, and the intersection point is located to the right of the center of mass, a stainless steel shim needs to be added between the front left or rear right connecting base and the fuselage to move the intersection point in the negative Y-axis direction; if the intersection point is located to the left of the center of mass, a stainless steel shim needs to be added between the front right or rear left connecting base and the fuselage to move the intersection point in the positive Y-axis direction. After adjustment, remeasure the pitch angle until ΔY ≤ 0.5.

[0074] (4) Measurement verification: After adjustment, repeat step 5, step 6 for verification until all deviations meet the requirements: | ΔX | ≤ 0.1°, | ΔY | ≤ 0.1°, and ΔY ≤ 0.5mm. - - -

[0075] At this point, the final dual-rocket boost unmanned aerial vehicle thrust line direction is obtained. When the real rocket is installed, only the real rocket is installed on the adjusted rocket mounting mechanism 9 by directly removing the rocket booster dummy 10, which can ensure the thrust line of the dual rocket.

[0076] The specific measurement adjustment process of the embodiment is described in detail in Figure 8 The embodiment establishes a set of convenient and reliable measurement, adjustment and installation process, ensures that the two side thrust lines are strictly symmetrical and coplanar on the center of gravity plane during launching, thereby improving the launching performance and flight safety of the unmanned aerial vehicle.

[0077] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.​

Claims

1. A thrust line measurement and adjustment device for a dual-rocket-boosted unmanned aerial vehicle, characterized in that, include: A three-axis centroid measurement device is used to measure the centroid of the UAV to be tested, which is mounted on it. A flexible clamping mechanism is installed on a triaxial centroid measuring device to connect the triaxial centroid measuring device and a drone, and can adjust the installation position of the drone on the triaxial centroid measuring device. Two rocket booster dummy components were installed on both sides of the drone under test to simulate a real rocket. Rocket mounting mechanism for adjustable connection of rocket booster dummy and drone under test; And a laser tracker, used to measure the coordinates of the target point of the triaxial centroid measurement device and the coordinates of the cylindrical feature points of the rocket booster dummy on both sides of the UAV; the laser tracker and the triaxial centroid measurement device are electrically connected to transmit the measurement data to the triaxial centroid measurement device for processing.

2. The thrust line measurement and adjustment device for a dual-rocket-boosted unmanned aerial vehicle according to claim 1, characterized in that, The triaxial centroid measuring device includes: Equipment base; The equipment measuring platform is installed on the equipment base. The equipment measuring platform includes a weighing platform and a tilting mechanism. The weighing platform is installed on the equipment base in a height-adjustable manner. The tilting mechanism is installed on the weighing platform and is used to adjust the attitude of the UAV under test to be horizontal, tilted to the left, and tilted to the right. The attitude tilt of the UAV is around the UAV's heading. The flexible clamping mechanism is installed on the tilting mechanism. Multiple pressure sensors are installed between the base and the weighing platform to obtain the weight of the measuring table and the objects mounted on it. The X-axis grating positioning mechanism is mounted on the equipment base and located at the front end of the equipment measuring table. The grating positioning mechanism is used to determine the heading direction of the UAV under test. The system also includes a control system for controlling the lifting and lowering of the weighing platform for weighing, controlling the tilting mechanism for posture adjustment, and processing the weighing data acquired under different postures. The control system is also used to acquire and process data collected by the laser tracker.

3. The thrust line measurement and adjustment device for a dual-rocket-boosted unmanned aerial vehicle according to claim 2, characterized in that, The tilting mechanism includes: The motor, installed at the bottom of the weighing platform, provides tilting power for the tilting mechanism; The transmission assembly, mounted on the weighing platform, is used for power transmission; And a tilting platform assembly, which is slidably supported on the weighing platform by a guide wheel mechanism. The tilting platform assembly includes a support frame and a tilting platform horizontally fixed on the support frame. An arc-shaped rack is installed on one side of the support frame. The motor output end and the input end of the transmission component are connected by a transmission mechanism. The output end of the transmission component meshes with the arc-shaped rack. The motor drives the arc-shaped rack to tilt on the guide wheel mechanism, thereby tilting the tilting platform. The flexible clamping mechanism is installed on the tilting platform.

4. The thrust line measurement and adjustment device for a dual-rocket-boosted unmanned aerial vehicle according to claim 3, characterized in that, The flexible clamping mechanism includes: Two guide rails are set in parallel with their ends aligned. Both guide rails are fixedly installed on the tilting platform. The direction of the guide rails is along the flight path of the UAV, and the two guide rails are installed symmetrically along the center line of the tilting platform. Four sliders are mounted in pairs on a guide rail. Two clamping base plates are arranged in parallel, with their ends mounted on the sliders of the two guide rails and fixedly connected to the sliders. A marking line is provided at the center of the clamping base plate along the flight direction to mark the center line of the flexible clamping mechanism. It also includes four quick-change fixtures, which are installed in pairs on the mounting base plate. The quick-change fixtures are used to connect the UAV under test.

5. The thrust line measurement and adjustment device for a dual-rocket-boosted unmanned aerial vehicle according to claim 4, characterized in that, The mounting base plate has a matrix array of multiple threaded holes for mounting different types of quick-change fixtures. The quick-change fixture is designed according to different specifications of UAVs and has a frame plate structure. The bottom plate of the quick-change fixture is fixedly connected to the mounting base plate by fasteners, and its top plate is connected to the support block of the UAV. The top plate is provided with strip holes. By adjusting the position of the fasteners in the strip holes, the mounting axis of the UAV can be adjusted.

6. The thrust line measurement and adjustment device for a dual-rocket-boosted unmanned aerial vehicle according to claim 1, characterized in that, The rocket installation mechanism includes an adjustment mounting base and a mounting frame. The adjustment mounting base is fixedly installed on the UAV, and the mounting frame connects the rocket booster dummy and the adjustment mounting base.

7. The thrust line measurement and adjustment device for a dual-rocket-boosted unmanned aerial vehicle according to claim 6, characterized in that, The mounting bracket includes a connecting base and a pressure block. The connecting base is fixedly connected to the drone body, while the pressure block and the connecting base are adjustable. The adjustment direction of the pressure block relative to the connecting base is vertical adjustment perpendicular to the horizontal plane.

8. A method for measuring and adjusting the thrust line of a dual-rocket-boosted unmanned aerial vehicle, the method employing the apparatus described in any one of claims 1-7, characterized in that, Includes the following steps: Step 1. Install the flexible clamping mechanism on the triaxial center of mass measuring equipment, start the triaxial center of mass measuring equipment, and measure the unloaded tare weight of the measuring table in three postures: horizontal, left tilt, and right tilt after the flexible clamping mechanism is installed. The control system calculates the center of mass coordinates of the measuring table in the unloaded state based on the measurement data and determines the tooling coordinate system of the measuring equipment. Step 2. Use rocket mounting mechanisms to pre-install rocket booster dummy parts on both sides of the UAV under test, then place the UAV on the flexible clamping mechanism, align the axial centerline of the UAV with the centerline of the flexible clamping mechanism, and fix the UAV and the flexible clamping mechanism together. Step 3. Start the three-axis centroid measurement equipment and measure the total weight of the UAV in three attitudes: horizontal, left tilt, and right tilt, after loading the UAV onto the measuring platform. The control system calculates the centroid spatial coordinates of the UAV in the tooling coordinate system of the measuring equipment based on the total weight of the UAV and the unloaded tare weight of the measuring platform. Step 4. Use a laser tracker to measure the target coordinates on the triaxial centroid measurement device and transmit them to the control system. Create a spatial reference plane through the measurement software built into the control system to obtain the laser coordinate system. The control system aligns the laser coordinate system with the tooling coordinate system of the measurement device to establish a unified coordinate system and form a measurement coordinate system. Step 5. Use a laser tracker to collect feature points on the cylindrical surfaces of the rocket booster dummy on both sides, control the system to obtain the coordinates of the feature points on the surface of the rocket booster dummy, and calculate and process to generate the axis of the rocket booster dummy on both sides, that is, to obtain the thrust line direction in the current installation state of the rocket booster dummy. Step 6. Based on the spatial coordinates of the UAV's center of mass in the coordinate system of the measuring equipment tooling, the control system creates the center of mass of the UAV in the measuring coordinate system and calculates the deviation values ​​between the axis of the two rocket booster dummy parts and the center of mass of the UAV. The deviation values ​​include: the pitch angle deviation between the axis of the two rocket booster dummy parts and the horizontal plane where the center of mass is located, and the inner flare angle deviation between the axis of the two rocket booster dummy parts and the vertical plane where the center of mass is located. Step 7. Based on the pitch angle deviation and flare angle deviation, adjust the installation position and attitude of the rocket booster dummy through the rocket installation mechanism, and then adjust the axis of the rocket booster dummy on both sides. After adjustment, repeat steps 5 and 6 for verification until the pitch angle deviation and flare angle deviation meet the design requirements. Thus, the final thrust line direction of the dual-rocket-boosted drone was obtained.

9. The thrust line measurement and adjustment method for a dual-rocket-assisted unmanned aerial vehicle according to claim 8, characterized in that, The method for adjusting the installation attitude of the rocket booster dummy in step 7 includes: adjusting the pitch angle deviation by moving the pressure block up and down, and adjusting the yaw angle deviation by adding a shim between the connecting base and the UAV fuselage.

10. The method for measuring and adjusting the thrust line of a dual-rocket-assisted unmanned aerial vehicle according to claim 8, characterized in that, The origin of the measurement coordinate system is the center of the equipment's measuring platform. The X-axis is forward along the UAV's flight path, the Z-axis is perpendicular to the horizontal plane and upward, and the Y-axis is perpendicular to the plane of symmetry of the UAV's fuselage, conforming to the right-hand rule.

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