Aircraft takeoff stress measuring device and aircraft takeoff safe taxiing lift envelope obtaining method

Abstract

The invention discloses an aircraft takeoff stress measuring device and an aircraft takeoff safe taxiing lift envelope obtaining method, and relates to the technical field of aircraft test flight tests.A target aircraft is carried and moved through a T-shaped body support provided with wheels, the T-shaped body support is matched with the approximate distribution of an aircraft landing gear, and the aircraft takeoff safety taxiing lift envelope is obtained. The undercarriage and the movable flat plates are connected through the connecting mechanism after the aircraft is supported and adjusted, accidental take-off caused by gust wind or unstable control over the speed of a sports car is prevented, and the vehicle traction rod is used for being connected with the sports car; the target aircraft is dragged to slide, the force borne by the aircraft in the off-frame and on-frame sliding process is fed back through the force measuring sensor, the force bearing condition of the aircraft is accurately measured, and the take-off state of the aircraft can be confirmed by combining the rudder deflection angle parameter and the sliding speed set in the testing process. And finally, determining a lift force safe taxiing envelope of the aircraft, so as to realize the flight test of the ultra-light large-wingspan aircraft.

Description

Technical Field

[0001] The present application relates to the technical field of aircraft flight testing, and in particular to a device for measuring aircraft takeoff force and a method for obtaining an aircraft takeoff safety glide lift envelope. Background Art

[0002] Currently, ultra-high-altitude, long-endurance drones powered by renewable energy, designed to cruise in near-space are a hot topic of research. These drones have a wide range of applications, including long-term reconnaissance and surveillance, environmental monitoring, and communications relay. Their key features include an extremely large wingspan, flexible structure, and ultra-light weight. Their unique design allows for relatively low airspeeds, typically between 45km / h and 90km / h. While taxiing on the ground, their theoretical takeoff speed is even lower, perhaps as low as 40km / h. Uncontrolled takeoffs can occur due to a certain rudder deflection angle, a slightly higher taxiing speed, or gusts of wind. These unintended takeoffs can easily cause damage to the aircraft, such as flexible wingspan breakage and landing gear deformation.

[0003] Compared with the past, after a traditional aircraft is successfully developed, the take-off speed will first be simulated according to the performance indicators and a predetermined value will be given. After multiple rounds of test verification, such as load calibration test, whole-aircraft vibration test, and wind tunnel test, it will undergo multiple rounds of ground low-speed taxiing, medium-speed taxiing, and high-speed taxiing before the first flight. After the flight parameters are judged to confirm that there are no problems with the functional indicators of each system, it can be launched after confirmation by the pre-first flight review.

[0004] However, the current traditional flight test methods before aircraft launch are not suitable for this type of ultra-light aircraft with a large wingspan. Summary of the Invention

[0005] The main purpose of this application is to provide an aircraft takeoff force measurement device and a method for obtaining the lift envelope of an aircraft takeoff safe glide, aiming to solve the problem that the aircraft flight test methods in the prior art are not suitable for ultralight large wingspan aircraft.

[0006] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows: In a first aspect, an embodiment of the present application provides an aircraft takeoff force measurement device, comprising: A T-shaped main body bracket, with wheels mounted on the bottom side of the T-shaped main body bracket; a plurality of movable flat plates, the plurality of movable flat plates being mounted on the top side of the T-shaped main body bracket, each movable flat plate being used to carry one landing gear of the target aircraft; A connecting mechanism is provided on the movable flat plate and is used to connect the movable flat plate with the landing gear it carries; Vehicle tow bar, which is used to connect the end of the T-shaped main bracket and the sports car; The force sensor is arranged on the bottom side of the movable flat plate and is used to detect the force applied when the target aircraft is being put on and taken off the platform.

[0007] In a possible implementation of the first aspect, a plurality of force sensors are provided on each movable plate, and the plurality of force sensors are evenly distributed on a bottom side of the movable plate.

[0008] In a possible implementation of the first aspect, four force sensors are provided on each movable plate, and the four force sensors are respectively provided at four corners of the bottom side of the movable plate.

[0009] In a possible implementation of the first aspect, the measuring device further includes a positioning module, which is disposed on the T-shaped main body bracket and is used for positioning the measuring device.

[0010] In a possible implementation of the first aspect, the positioning module includes a GPS collector and a GPS antenna, and the GPS antenna is disposed at a corner of an intersection of the T-shaped main body support.

[0011] In a possible implementation of the first aspect, the connection mechanism on each movable platform includes four connection ropes, one end of the four connection ropes is respectively connected to four corners of the movable platform, and the other end of the four connection ropes is connected to a landing gear carried by the movable platform.

[0012] In a possible implementation of the first aspect, the measuring device further includes three connecting plates, which are detachably arranged at the ends of the T-shaped main body bracket and at both ends of the cross frame of the T-shaped main body bracket, and close to the side where the vehicle tow bar is arranged.

[0013] In a possible implementation of the first aspect, a fixed flat panel is provided at the intersection of the T-shaped main support, and a data acquisition recorder and a battery are provided on the fixed flat panel. The data acquisition recorder is used to record data of electronic devices in the measuring device, and the battery is used to power the electronic devices in the measuring device.

[0014] In a second aspect, an embodiment of the present application provides a method for obtaining a lift envelope for safe taxiing during takeoff of an aircraft, comprising the following steps: Connecting and installing the target aircraft to the measuring device; wherein the measuring device is the aircraft takeoff force measuring device provided in any one of the first aspects above; Adjust the target aircraft's rudder angle parameters and start the car until the target aircraft completes a taxi and then dismounts. Obtaining aircraft force data based on force data detected by the measuring device when the target aircraft is being put on and taken off the aircraft; Obtain the aircraft force state according to the aircraft force data, aircraft rudder angle parameters, and aircraft taxiing speed data; When the aircraft is subjected to a stress state where gravity is greater than lift, the aircraft stress state is compared with the simulation result during aircraft design, the simulation value is corrected and the process of connecting and installing the target aircraft to the measuring device is returned to. The aircraft rudder angle parameters and the speed of the sports car are modified until the aircraft stress state is such that lift is greater than gravity, thereby confirming the lift envelope for safe takeoff and taxiing of the target aircraft.

[0015] In a possible implementation of the second aspect, obtaining aircraft force data based on force data detected by a measuring device when the target aircraft is being put on and taken off the aircraft includes: According to the sum of the forces detected by the four force sensors on the measuring device, the force data of the target aircraft when it is put on the platform and the force data of the target aircraft when it is taken off the platform are obtained respectively; The aircraft force data is obtained based on the difference between the force data when the target aircraft is put on the platform and the force data when it is taken off the platform.

[0016] Compared with the prior art, the present invention has the following advantages: Embodiments of the present application provide an aircraft takeoff force measurement device and a method for obtaining the safe taxiing lift envelope for an aircraft. The measurement device includes a T-shaped main frame, multiple movable flat plates, a connecting mechanism, a vehicle tow bar, and a force sensor. A target aircraft is carried and moved by means of a T-shaped main frame with wheels. The T-shaped main frame conforms to the approximate distribution of the aircraft's landing gear, and the multiple movable flat plates are used to fine-tune the connection position between the movable flat plates and the landing gear. After the aircraft support is adjusted, the landing gear is connected to the movable flat plates using the connecting mechanism to prevent accidental takeoffs caused by gusts of wind or unstable speed control of the sports car. The vehicle tow bar is used to connect to the sports car to tow the target aircraft for taxiing. The forces applied to the aircraft during taxiing are fed back through the force sensor, enabling accurate measurement of the aircraft's forces. Combined with the aircraft's rudder angle parameters and taxiing speed set during the test, the aircraft's takeoff state can be confirmed, the taxiing limit can be obtained, and ultimately the safe taxiing lift envelope of the aircraft can be determined, thereby enabling flight testing of ultralight aircraft with large wingspans. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic structural diagram of an aircraft takeoff force measurement device according to an embodiment of the present application; Figure 2 A schematic structural diagram of a connecting mechanism in an aircraft takeoff force measurement device provided in an embodiment of the present application; Figure 3 A flowchart of a method for obtaining a safe taxiing lift envelope for aircraft takeoff provided in an embodiment of the present application; Figure 4 A flowchart of a method for obtaining a lift envelope for safe taxiing during takeoff of an aircraft provided in an embodiment of the present application, in one embodiment; Markings in the figure: 1-force sensor, 2-GPS antenna, 3-GPS collector, 4-data acquisition recorder, 5-battery, 6-connection plate, 7-movable flat plate, 8-fixed flat plate, 9-vehicle tow bar, 10-control switch, 11-connection mechanism, 12-landing gear. DETAILED DESCRIPTION

[0018] It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application.

[0019] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0020] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0021] In this application, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0022] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. In addition, the meaning of "and / or" appearing throughout the text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme in which A and B are satisfied at the same time. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement it. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0023] Refer to the attached Figure 1 An embodiment of the present application provides an aircraft takeoff force measurement device, comprising: a T-shaped main body bracket, a plurality of movable flat plates 7, a connecting mechanism 11, a vehicle tow bar 9, and a force sensor 1, wherein a wheel is installed on the bottom side of the T-shaped main body bracket; a plurality of movable flat plates 7 are installed on the top side of the T-shaped main body bracket, and each movable flat plate 7 is used to carry a landing gear 12 of a target aircraft; a connecting mechanism 11 is provided on the movable flat plate 7, and the connecting mechanism 11 is used to connect the movable flat plate 7 and the landing gear 12 it carries; the vehicle tow bar 9 is used to connect the end of the T-shaped main body bracket and the sports car; the force sensor 1 is provided on the bottom side of the movable flat plate 7, and the force sensor 1 is used to detect the force applied to the target aircraft when it is taking off and landing.

[0024] In this embodiment, a target aircraft is carried and moved by providing a T-shaped main body support with wheels. The T-shaped main body support conforms to the approximate distribution of the aircraft landing gear, and a plurality of movable flat plates 7 are provided to fine-tune the receiving position of the movable flat plates 7 and the landing gear 12. After the aircraft support adjustment is completed, the landing gear 12 is connected to the movable flat plates 7 using a connecting mechanism 11 to prevent accidental takeoff caused by gusts of wind or unstable speed control of the sports car. The vehicle tow bar 9 is used to connect with the sports car to tow the target aircraft for taxiing. The force applied to the aircraft during taxiing is fed back through the force sensor 1 to achieve accurate measurement of the aircraft's force conditions. Combined with the aircraft rudder angle parameters and taxiing speed set during the test, the aircraft's takeoff state can be confirmed, the taxiing limit can be obtained, and the aircraft's lift safety taxiing envelope can be ultimately determined, thereby achieving flight testing of ultralight aircraft with a large wingspan.

[0025] It should be noted that the end of the T-shaped main support refers to the end of the vertical part of the T-shaped structure, that is, as shown in the attached Figure 1 The bottom end of the T-shaped main bracket is shown. Figure 1 The T-shaped main frame shown in the figure is in a vertical state, but in actual use it is in a horizontally tilted state. Therefore, the front side shown in the figure is the top side of the T-shaped main frame, and the opposite side is its bottom side. The movable plate 7 provided on the bottom side is shown with a dotted line to indicate that it is in an attached position. Figure 1The movable flat plate 7 can be connected to the T-shaped main body bracket by a sliding connection such as a slide connection, or can be clamped with the T-shaped main body bracket and can slide relative to each other, so that it can move along the bracket of the T-shaped main body bracket. The purpose of the T-shaped main body bracket is to match the target aircraft, that is, the landing gear 12 distribution of an ultralight large wingspan aircraft. The three landing gears 12 are distributed in a triangular shape, so the movable flat plate 7 is respectively arranged at the end of the T-shaped main body bracket and at both ends of the cross frame of the T-shaped main body bracket. In the actual connection and installation, the movable flat plate 7 is moved to achieve accurate connection of the movable flat plate 7 to the landing gear 12.

[0026] In one embodiment, multiple force sensors 1 are provided on each movable plate 7, and the multiple force sensors 1 are evenly distributed on the bottom side of the movable plate 7. The force sensor 1 is located between the movable plate 7 and the T-shaped main body bracket, and feedbacks the pressure of the landing gear 12 on the movable plate 7. In order to ensure uniform force and accurate feedback data, multiple evenly distributed force sensors 1 are provided for collection, as shown in the attached figure. Figure 1 The figure shows a configuration in which four force sensors 1 are arranged in a group. The four force sensors 1 can be evenly distributed in a circular array around the axis of the movable plate 7, or can be arranged in a circular array as shown in the attached figure. Figure 1 In the manner shown, the movable plate 7 is matched with its shape and is respectively arranged at the four corners of the bottom side of the movable plate.

[0027] In one embodiment, the measuring device further includes a positioning module, which is disposed on a T-shaped main body support and is used to position the measuring device. A detection function is added to the measuring device so that the measuring device can not only obtain force data but also detect the taxiing speed based on the positioning module. Positioning modules such as GPS positioning, laser radar positioning, RFID positioning, and Bluetooth positioning are examples. As in the above embodiment, the provision of the positioning module not only increases the functionality of the measuring device, but also locates the position of the measuring device, i.e., the position of the target aircraft, and thus can measure the speed, thereby reducing the workload of measuring the speed separately and compensating for the effects of unstable speed control of the sports car. This is because the sports car speed control can only provide an approximate speed, and a more accurate speed needs to be calculated separately, while the positioning module can provide accurate data. The displacement information obtained through the positioning module can be combined with the taxiing time information to obtain the taxiing speed.

[0028] The embodiment of the present application provides an implementation method of GPS positioning. Specifically, the positioning module includes a GPS collector 3 and a GPS antenna 2. The GPS antenna 2 is set at the corner of the intersection of the T-shaped main body bracket. As in the above implementation method, a GPS positioning method is set to be responsible for the positioning of the measuring device, that is, the time synchronization positioning function of the data acquisition system. The measuring device is positioned by setting the GPS collector 3 and the GPS antenna 2. The GPS collector 3 collects the position data of the measuring device, and the GPS antenna 2 is used to transmit and receive signals to cooperate with the positioning. In order to avoid the influence of the aircraft body on the positioning, the GPS antenna 2 is set as shown in the attached figure. Figure 1 The corners of the intersection of the T-shaped main body bracket are shown in FIG.

[0029] In one embodiment, the connection mechanism 11 on each movable platform 7 includes four connection ropes, one end of each of the four connection ropes 11 is connected to the four corners of the movable platform 7, and the other end is connected to the landing gear 12 carried by the movable platform 7. The movable platform 7 is connected to the landing gear 12 to ensure the stability of the test. The landing gear 12 is evenly pulled from the four corners of the movable platform 7 by the four connection ropes 11, as shown in the attached figure. Figure 2 As shown, the connecting rope 11 is in a loose state to prevent the aircraft from taking off unexpectedly due to gusts of wind or unstable speed control of the sports car.

[0030] In one embodiment, the measurement device further includes three connecting plates 6, which are detachably mounted at the ends of the T-shaped main frame and at both ends of the cross frame of the T-shaped main frame, and are located near the side where the vehicle tow bar 9 is located. The side near the vehicle tow bar 9 faces the sliding direction, that is, the direction of the sports car connected to the vehicle tow bar 9, and is used to connect the ground to the T-shaped main frame, facilitating the movement of the target aircraft to the measurement device and to the ground.

[0031] In one embodiment, a fixed plate 8 is provided at the intersection of the T-shaped main frame, and a data acquisition recorder 4 and a battery 5 are provided on the fixed plate 8. The data acquisition recorder 4 is used to record the data of the electronic components in the measuring device, and the battery 5 is used to power the electronic components in the measuring device. As in the above embodiment, some device modules in the integrated measuring device, such as the attached Figure 1As shown, the fixed flat plate 8 is arranged at the intersection of the T-shaped main body bracket, and is used to carry some device modules, such as the GPS collector 3 is arranged at a corner of the fixed flat plate 8, and the data acquisition recorder 4 is fixed at a corner of the fixed flat plate 8, which is used to record the detection data of the force sensor 1 and the GPS data of the GPS collector 3. The battery 5 and the control switch 10 are respectively arranged at a corner of the fixed flat plate 8. The various electronic components are connected by electrical cables. The battery 5 is responsible for powering the electronic components, that is, the power supply of the entire data acquisition system. The control switch 10 is responsible for electrical control connection and data recording control. The power-on control of each electronic component is realized by turning the control switch 10 on and off.

[0032] As attached Figure 3 As shown, based on the same inventive concept as in the above embodiment, the embodiment of the present application further provides a method for obtaining a lift envelope for safe taxiing of an aircraft during takeoff, comprising the following steps: S10: Connect and install the target aircraft to the measuring device; wherein the measuring device is the aircraft takeoff force measuring device provided in an embodiment of the present application.

[0033] S20: Adjust the target aircraft's rudder angle parameters and start the sports car until the target aircraft is dismounted after completing a taxi.

[0034] S30: Obtaining aircraft force data based on the force data of the target aircraft when it is put on and taken off the aircraft, detected by the measuring device.

[0035] S40: Obtaining the aircraft force state according to the aircraft force data, the aircraft rudder angle parameter, and the aircraft taxiing speed data.

[0036] S50: When the aircraft is subjected to a force state in which gravity is greater than lift, the aircraft is subjected to a force state that is compared with a simulation result during aircraft design, the simulation value is corrected, and the process of connecting and installing the target aircraft to the measuring device is returned to. The aircraft rudder angle parameter and the speed of the sports car are modified until the aircraft is subjected to a force state in which lift is greater than gravity, thereby confirming the lift envelope for safe takeoff taxiing of the target aircraft.

[0037] In this embodiment, the takeoff safety taxi lift envelope, also known as the taxi safety envelope, is defined as the lift equals the weight when taxiing speed reaches a certain value at various rudder deflection angles. This places the aircraft in a critical pre-takeoff state. Once the speed increases further, the lift becomes greater than the weight, and the aircraft begins to take off. In the event of an unexpected situation, such as a headwind, the aircraft could suddenly take off and then land, potentially damaging the aircraft. During taxiing, the safety rope prevents this from happening. To ensure the aircraft is completed safely and reliably during its initial launch, thorough ground testing is required.

[0038] The measurement device provided in the embodiments of the present application measures the force data of the target aircraft during the test of loading and unloading. For example, each group of four force sensors 1 is provided. The sum of the forces measured by each group of four force sensors at a certain moment when the three groups of force sensors are in the loading phase is obtained: Nloading = N1 + N2 + N3 + N4. When the aircraft is unloading, Nunloading = N1 + N2 + N3 + N4. The difference between the two is used to calculate the force on the aircraft, i.e., the force N applied to the aircraft during taxiing = Nloading - Nunloading. The speed measured at the corresponding moment is obtained; the force on the aircraft is determined by analyzing the data at the corresponding moment, when the speed and rudder deflection parameters are determined. When the force on the aircraft is pressure on the combined force sensor, it is confirmed that the aircraft is in a state where gravity is greater than lift. When the combined force sensor senses tension, it is confirmed that the aircraft is in a state where lift is greater than weight.

[0039] That is, based on the force data of the target aircraft when it is being put on and taken off the platform detected by the measuring device, the force data of the aircraft is obtained, including: According to the sum of the forces detected by the four force sensors on the measuring device, the force data of the target aircraft when it is put on the platform and the force data of the target aircraft when it is taken off the platform are obtained respectively; The aircraft force data is obtained based on the difference between the force data when the target aircraft is put on the platform and the force data when it is taken off the platform.

[0040] Compare the simulation results during aircraft design, correct the simulation values, repeat the test steps, modify the rudder angle and taxiing speed until the measured aircraft takeoff lift is greater than the aircraft itself weight, confirm the taxiing limit under different parameters, and finally determine the taxiing safety envelope.

[0041] Refer to the attached Figure 4 , as attached Figure 4 The present application is further described below with reference to the following embodiments: First, fix the aircraft on the full-force measurement device, that is, the aircraft takeoff force measurement device, remove the vehicle tow bar 9, place the connecting plate 6 between the ground and the full-force device, push the aircraft onto the measurement device, connect the connecting plate 6, connect the vehicle tow bar 9 and the sports car, connect the tow bar to the measurement device and the sports car, and put it on the shelf for testing.

[0042] After determining the parameters such as the rudder angle parameter and the speed of the sports car, the acquisition and recording control switch is turned on. Then, the car moves in a straight line according to the determined parameters, controlling the direction and speed of the sports car and moving forward at a constant speed along the straight line as much as possible. After completing a taxi, the recorded data is obtained for analysis, the aircraft is taken off the platform for maintenance and inspection, and the travel speed and rudder parameters are combined with GPS to calculate the travel speed and perform data analysis to determine the force on the aircraft. The specific speed is obtained through GPS displacement and time information V=s / t, and the speed measured at the corresponding moment is obtained. By analyzing the data, the force on the aircraft is obtained at the corresponding moment when the speed and rudder parameters are determined. When the force on the aircraft is pressure on the combined force sensor, it is confirmed that the aircraft is in a state where gravity is greater than lift. When the combined force sensor senses tension, it is confirmed that the aircraft is in a state where lift is greater than weight. Comparing the simulation results with those from the aircraft design, the simulation values are corrected, and then parameters and speeds are changed. Returning to the installation step, the rudder angle and taxiing speed are modified, and the preset rudder angle parameters and speed are modified in an approximate manner until the measured takeoff lift exceeds the aircraft's weight, confirming takeoff status. The safe taxiing envelope for lift is confirmed, suitable for low-speed, ultra-large wingspan aircraft, ensuring safe takeoff for super-sized aircraft, especially during the maiden flight.

[0043] Take three groups of experiments as an example. In the first group, the rudder angle is set to a certain value, and the traction is carried out at a relatively stable speed A for a fixed time B. The speed A is increased and the step size is fixed to stabilize the traction and slide for a fixed time B. By recording the GPS speed, time and the force N during the slide, the curve is drawn using MATLAB. The second group changed the rudder deflection angle and repeated the test process of the first group to obtain the lift, speed and time curves; The third group changed the rudder angle again and carried out the same test process as the first group. Finally, they made corrections by comparing the laboratory simulation results to provide a safety guarantee basis for launch.

[0044] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or system. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or system comprising the element.

[0045] The serial numbers of the above embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0046] In summary, embodiments of the present application provide an aircraft takeoff force measurement device and a method for obtaining a safe takeoff taxiing lift envelope. The measurement device includes: a T-shaped main frame, multiple movable flat plates, a connecting mechanism, a vehicle tow bar, and a force sensor. A target aircraft is carried and moved by means of a T-shaped main frame with wheels. The T-shaped main frame conforms to the approximate distribution of the aircraft's landing gear, and the multiple movable flat plates are used to fine-tune the connection position between the movable flat plates and the landing gear. After the aircraft support is adjusted, the landing gear is connected to the movable flat plates using the connecting mechanism to prevent accidental takeoffs caused by gusts of wind or unstable speed control of the sports car. The vehicle tow bar is used to connect to the sports car to tow the target aircraft for taxiing. The forces applied to the aircraft during taxiing are fed back via the force sensor, enabling accurate measurement of the aircraft's forces. Combined with the aircraft's rudder angle parameters and taxiing speed set during the test, the aircraft's takeoff state can be confirmed, the taxiing limit can be obtained, and ultimately the aircraft's safe taxiing lift envelope can be determined, thereby enabling flight testing of ultralight, large-wingspan aircraft.

[0047] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. An aircraft takeoff force measurement device, characterized in that: include: A T-shaped main body bracket, with wheels mounted on the bottom side of the T-shaped main body bracket; a plurality of movable flat panels, wherein the plurality of movable flat panels are mounted on the top side of the T-shaped main body support, and each of the movable flat panels is used to carry a landing gear of the target aircraft; a connecting mechanism, the connecting mechanism being provided on the movable flat plate and being used for connecting the movable flat plate with the landing gear carried by the movable flat plate; A vehicle tow bar, the vehicle tow bar being used to connect the end of the T-shaped main body bracket with the sports car; A force sensor is provided on the bottom side of the movable flat panel, and is used to detect the force applied to the target aircraft when it is being put on and taken off the aircraft.

2. The aircraft takeoff force measurement device according to claim 1, characterized in that: A plurality of the force sensors are provided on each movable plate, and the plurality of force sensors are evenly distributed on the bottom side of the movable plate.

3. The aircraft takeoff force measurement device according to claim 2, characterized in that: Four force sensors are provided on each movable plate, and the four force sensors are respectively provided at four corners of the bottom side of the movable plate.

4. The aircraft takeoff force measurement device according to claim 1, characterized in that: The measuring device further comprises a positioning module, which is arranged on the T-shaped main body bracket and is used for positioning the measuring device.

5. The aircraft takeoff force measurement device according to claim 4, characterized in that: The positioning module includes a GPS collector and a GPS antenna, and the GPS antenna is arranged at the corner of the intersection of the T-shaped main body bracket.

6. The aircraft takeoff force measurement device according to claim 1, characterized in that: The connecting mechanism on each movable platform includes four connecting ropes, one end of each of the four connecting ropes is connected to the four corners of the movable platform respectively, and the other end of each of the four connecting ropes is connected to the landing gear carried by the movable platform.

7. The aircraft takeoff force measurement device according to claim 1, characterized in that: The measuring device further comprises three connecting plates, which are detachably arranged at the end of the T-shaped main body bracket and at both ends of the cross frame of the T-shaped main body bracket, and close to the side where the vehicle traction rod is arranged.

8. The aircraft takeoff force measurement device according to claim 1, characterized in that: A fixed flat panel is provided at the intersection of the T-shaped main support, on which a data acquisition recorder and a battery are provided. The data acquisition recorder is used to record data of the electronic components in the measuring device, and the battery is used to power the electronic components in the measuring device.

9. A method for obtaining a lift envelope for safe taxiing during takeoff, characterized in that: The following steps are involved: Connecting and installing the target aircraft to the measuring device; wherein the measuring device is the aircraft takeoff force measuring device according to any one of claims 1 to 8; Adjust the aircraft rudder deflection angle parameter of the target aircraft and start the sports car until the target aircraft is dismounted after completing a taxiing; Obtaining aircraft force data based on the force data of the target aircraft when it is put on and taken off the aircraft detected by the measuring device; Obtaining an aircraft force state according to the aircraft force data, the aircraft rudder angle parameter, and the aircraft taxiing speed data; When the aircraft is subjected to a stress state where gravity is greater than lift, the aircraft stress state is compared with a simulation result during aircraft design, the simulation value is corrected, and the process of connecting and installing the target aircraft to the measuring device is returned to. The aircraft rudder angle parameter and the speed of the sports car are modified until the aircraft stress state is such that lift is greater than gravity, thereby confirming the lift envelope for safe takeoff and taxiing of the target aircraft.

10. The method for obtaining the lift envelope for safe taxiing during takeoff according to claim 9, characterized in that: The step of obtaining aircraft force data based on the force data of the target aircraft when it is put on and taken off the aircraft, detected by the measuring device, comprises: Obtaining force data of the target aircraft when it is being put on the flight deck and force data of the target aircraft when it is being taken off the flight deck, respectively, based on the sum of the forces detected by the four force sensors on the measuring device; The aircraft force data is obtained according to the difference between the force data when the target aircraft is put on the platform and the force data when the target aircraft is taken off the platform.

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