Model ground test device of unmanned aerial vehicle and test method applying same

Abstract

The invention discloses a model ground test device of an unmanned aerial vehicle and a test method using the same, and the device and the method are characterized in that the unmanned aerial vehicle is carried by a test vehicle which can be driven to move, and a plurality of sensors are arranged on the unmanned aerial vehicle, so that lift force, resistance, propeller torque and motor voltage and current during flight of the unmanned aerial vehicle are obtained through simulation; and parameter information such as force effect, conversion efficiency, power, endurance and voyage is obtained through derivation, and data support is provided for iterative design and flight experiments of the unmanned aerial vehicle.

Description

Technical Field

[0001] The invention relates to multi-rotor unmanned aerial vehicle experiment and test, and in particular to a model ground test device of an unmanned aerial vehicle and a test method using the same. Background Art

[0002] The design process of multi-rotor UAVs requires the auxiliary design of performance parameters such as lift, drag, propeller force efficiency, and propeller motor conversion efficiency in actual flight. However, due to the complexity of the actual flight environment, traditional test methods such as wind tunnel tests, bench tests, and CFD simulation tests cannot accurately obtain the above parameters. In addition, due to the generally large size and mass of the measurement equipment, it is impossible to carry additional measurement equipment to measure the above parameters in actual flight. Even if the measurement equipment is forcibly carried for flight experiments, the measurement results will be inaccurate due to the weight and volume of the measurement equipment itself. Therefore, the measurement of performance parameters such as lift, drag, propeller force efficiency, and propeller motor conversion efficiency in actual flight is a difficult problem to be solved. At present, there is no experimental method and supporting equipment that can accurately obtain these performance parameters, and basically only theoretical calculations can be used to obtain them.

[0003] In addition, as people's research on aircraft continues to deepen, various types of special aircraft continue to come out, and various new aircraft need to obtain corresponding aircraft performance parameters accurately and timely through experiments.

[0004] Based on the above problems, the inventors have conducted an in-depth analysis of the testing methods of multi-rotor UAVs, in the hope of designing a test device and method that can solve the above problems and obtain aircraft performance parameters, and a model ground test device for UAVs and a test method using the device that can accurately, quickly and conveniently obtain aircraft performance parameters. Summary of the invention

[0005] In order to overcome the above-mentioned problems, the inventors have conducted intensive research and designed a model ground test device for UAV and a test method using the same. In the device and method, a UAV is carried on a drivable and movable test vehicle, and multiple sensors are arranged on the UAV to simulate the lift, drag, propeller torque, motor voltage and current of the UAV during flight, and then the force efficiency, conversion efficiency, power, flight time, range and other parameter information are derived, providing data support for the iterative design and flight experiments of the UAV, thereby completing the present invention.

[0006] Specifically, the object of the present invention is to provide a model ground test device for an unmanned aerial vehicle, the device comprising a drivable and movable test vehicle 1, a support frame 2 is arranged on the test vehicle 1, and a test platform 5 is arranged on the support frame 2;

[0007] The support frame 2 is a retractable support frame;

[0008] The unmanned aerial vehicle 7 to be tested is installed on the test platform 5 .

[0009] The test platform 5 is provided with two slide rails 9 arranged parallel to each other; the length direction of the slide rails 9 is consistent with the traveling direction of the test vehicle 1.

[0010] The slide rail 9 is provided with a slider 10 which can slide back and forth along the length direction thereof.

[0011] A tension sensor 11 is installed on the slider 10, and the lift of the drone is measured by the tension sensor 11;

[0012] The test platform 5 is also provided with an angle adjustment device 13, through which the angle between the drone plane and the horizontal plane is adjusted to simulate the pitch angle of the drone in actual flight;

[0013] The drone is mounted on the angle adjustment device 13 .

[0014] There are two angle adjustment devices 13, one of which is provided on each slide rail 9;

[0015] The angle adjustment device 13 is connected to the slider 10 via a tension sensor 11 , and two tension sensors 11 and two sliders 10 are correspondingly arranged under each angle adjustment device 13 .

[0016] Among them, a front connecting rod 14 and a rear connecting rod 15 are connected between the two angle adjustment devices 13; the two angle adjustment devices 13 move synchronously with the front connecting rod 14 and the rear connecting rod 15;

[0017] On the test platform 5 , a six-degree-of-freedom force sensor 8 is also arranged between the front link 14 and the rear link 15 .

[0018] An amplifier 16 and a data collector 17 are installed on the test platform 5. The amplifier 16 is used to amplify the voltage signal of the sensor, and the data collector 17 is used to collect the voltage signal of the amplifier 16 and convert it into a digital signal for transmission to a computer terminal.

[0019] The drone 7 includes a fuselage 23, on which a main propeller 20, a main propeller motor 21 and a main propeller motor support 22 are arranged;

[0020] Wherein, a tension-torsion sensor 27 is provided between the main propeller motor 21 and the main propeller motor support 22;

[0021] Preferably, the UAV 7 is optionally provided with a tail thrust propeller 24, a tail thrust propeller motor 25 and a tail thrust propeller motor support 26;

[0022] Correspondingly, a tension-torsion sensor 27 is provided between the tail thrust propeller motor 25 and the tail thrust propeller motor support 26 .

[0023] The drone 7 is also provided with a rotation speed sensor 28, a voltage and current sensor 29, a flight controller 30 and a battery 31;

[0024] The speed sensor 28 is used for the speed of the main propeller motor 21 and the tail propeller 24;

[0025] The voltage and current sensor 29 is used to measure the voltage and current input to the main propeller motor 21 and the tail propeller motor 25;

[0026] The flight controller 30 is used to provide control signals to the motor, and the battery 31 is used to supply power to the drone 7 .

[0027] A pitot tube 19 is installed just in front of the center of gravity of the drone 7; the pitot tube 19 is used to measure the incoming flow velocity in front of the drone.

[0028] The present invention also provides a test method for a multi-rotor UAV, which is implemented by the UAV model ground test device described above.

[0029] The method comprises the following steps:

[0030] Step 1, retrieve the propeller motor PWM signal, flight speed and pitch angle of the UAV to be tested during the actual flight test; and input the propeller motor PWM signal into the flight controller 30;

[0031] Step 2, adjusting the angle adjustment device 13 so that the pitch angle of the UAV is consistent with the pitch angle during the actual flight test;

[0032] Step 3, controlling the test vehicle 1 to travel at a constant speed according to a set speed;

[0033] Step 4, collecting and recording data from the tension sensor 11, the tension-torsion sensor 27, the rotation speed sensor 28, the voltage and current sensor 29, and the pitot tube 19.

[0034] The beneficial effects of the present invention include:

[0035] (1) The model ground test device of the UAV provided by the present invention and the test method using the same can simulate the actual flight of the multi-rotor UAV, reduce the accidental damage of the UAV caused by low reliability in the early stage of design, and have high test safety;

[0036] (2) According to the model ground test device of the UAV provided by the present invention and the test method using the same, by simulating the actual flight of the multi-rotor UAV, the performance parameters such as lift, drag, propeller force efficiency, propeller motor conversion efficiency, etc. in the actual flight of the multi-rotor UAV can be accurately predicted, providing a basis for the design of the multi-rotor UAV. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic diagram showing the overall structure of a model ground test device for an unmanned aerial vehicle according to a preferred embodiment of the present invention is shown;

[0038] Figure 2 A schematic diagram of the structure of a test platform in a model ground test device of an unmanned aerial vehicle according to a preferred embodiment of the present invention is shown;

[0039] Figure 3 A schematic diagram of the structure of a tailless UAV in a model ground test device of a UAV according to a preferred embodiment of the present invention is shown;

[0040] Figure 4 A schematic structural diagram of a tail-pusher UAV in a model ground test device of a UAV according to a preferred embodiment of the present invention is shown.

[0041] Description of Reference Numerals

[0042] 1- Test vehicle

[0043] 2-Support frame

[0044] 3-Lower support frame

[0045] 4-Upper support frame

[0046] 5-Testing Platform

[0047] 6-Shock Absorption Device

[0048] 7- Drone

[0049] 8-6-DOF force sensor

[0050] 9-Slide rail

[0051] 10- Slider

[0052] 11-Tension sensor

[0053] 12-Limiting block

[0054] 13-Angle adjustment device

[0055] 14-Front connecting rod

[0056] 15-Rear connecting rod

[0057] 16-Amplifier

[0058] 17-Data Collector

[0059] 18-Pitot support bracket

[0060] 19- Pitot

[0061] 20-Main propeller

[0062] 21-Main propeller motor

[0063] 22-Main propeller motor support

[0064] 23-Body

[0065] 24-Tail Pusher Propeller

[0066] 25-Tail propeller motor

[0067] 26-Tail propeller motor support

[0068] 27-Tension and twist sensor

[0069] 28-Speed ​​sensor

[0070] 29. Voltage and current sensor

[0071] 30-Flight Controller

[0072] 31-Battery

[0073] 32-Landing Gear DETAILED DESCRIPTION

[0074] The present invention will be further described in detail below through the accompanying drawings and embodiments. Through these descriptions, the characteristics and advantages of the present invention will become more clear and distinct.

[0075] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0076] According to the present invention, a model ground test device of an unmanned aerial vehicle is provided, such as Figure 1 As shown in , the device comprises a drivable and movable test vehicle 1, a support frame 2 is arranged on the test vehicle 1, and a test platform 5 is arranged on the support frame 2;

[0077] The support frame 2 is a retractable support frame; the support frame 2 includes a lower support frame 3 located below and an upper support frame 4 located above, the upper support frame 4 can slide back and forth in the lower support frame 3, and can be locked at any height position, and the height of the support frame 2 can be set as needed, for example, the highest can reach about 3m. In this application, by setting the support frame 2 as a retractable support frame, the ground effect of the drone blades during the measurement process can be eliminated, while ensuring that the flow in front of the drone is a horizontal flow.

[0078] A shock absorbing device 6 is provided between the support frame 2 and the test platform 5; the shock absorbing device 6 is provided to reduce the measurement error caused by the vibration when the test vehicle moves.

[0079] The unmanned aerial vehicle 7 to be tested is installed on the test platform 5 .

[0080] Among them, Figure 2 As shown in , the test platform 5 is provided with two slide rails 9 arranged parallel to each other; the length direction of the slide rail 9 is consistent with the travel direction of the test vehicle 1, so as to ensure that the UAV to be tested can move forward and backward along the speed direction;

[0081] A slider 10 capable of reciprocating along the length direction is arranged on the slide rail 9, and a ball is arranged inside the slider 10, so as to reduce the friction resistance between the slide rail 9 and the slider 10 as much as possible; the length of the slide rail 9 and the distance between the two slide rails 9 are selected and set according to the size of the UAV model, for example, the length of the slide rail 9 is 500mm to 1200mm, and the distance between the two slide rails 9 is 400mm to 1000mm. Preferably, the length of the slide rail 9 is 800mm, and the distance between the two slide rails 9 is 600mm; preferably, the sliding stroke of the slider is 1mm.

[0082] Limit blocks 12 are also provided at both ends of the slide rail 9 to limit the sliding stroke of the slider 10 to ensure that the slider 10 does not detach from the limit blocks 12. By setting the limit blocks 12, the sliding stroke of the slider is 1 mm. Too large a stroke may easily cause damage to the slider 10.

[0083] A tension sensor 11 is installed on the slider 10, and the lift of the drone is measured by the tension sensor 11; the range of the tension sensor 11 is ±500N, and the accuracy is 0.1%FS: the number of the tension sensors 11 is 4, which is consistent with the number of main propellers. Preferably, the tension sensor in this application uses the SBT673 sensor produced by Guangzhou Sparto Company.

[0084] The test platform 5 is also provided with an angle adjustment device 13, through which the angle between the drone plane and the horizontal plane is adjusted to simulate the pitch angle of the drone in actual flight;

[0085] The UAV is mounted on the angle adjustment device 13. The landing gear of the UAV is mounted on the angle adjustment device 13.

[0086] Preferably, the adjustment range of the angle adjustment device 13 is 0 to 30°.

[0087] Preferably, two angle adjustment devices 13 are provided, and one angle adjustment device 13 is provided on each slide rail 9;

[0088] The angle adjustment device 13 is connected to the slider 10 via the tension sensor 11, and two tension sensors 11 and two sliders 10 are correspondingly arranged under each angle adjustment device 13. That is, four sliders are arranged.

[0089] Preferably, one end of the angle adjustment device 13 is hinged to the landing gear, and the other end is provided with a plurality of mounting holes, and the heights of the mounting holes are different. The landing gear can be installed to different mounting holes as needed, thereby realizing the adjustment setting of the inclination angle of the landing gear and the adjustment of the pitch angle.

[0090] Preferably, a front link 14 and a rear link 15 are connected between the two angle adjustment devices 13; the two angle adjustment devices 13 move synchronously with the front link 14 and the rear link 15;

[0091] On the test platform 5, a six-degree-of-freedom force sensor 8 is also arranged between the front link 14 and the rear link 15. The total resistance of the drone is measured by the six-degree-of-freedom force sensor 8. The distance between the front link 14 and the six-degree-of-freedom tension sensor 11 is 1 mm, and the distance between the rear link 15 and the six-degree-of-freedom tension sensor 11 is 1 mm, which allows a small amount of movement and is not easy to cause sensor damage. The six-degree-of-freedom force sensor in this application uses the K6D40 sensor produced by the German ME company.

[0092] The six-degree-of-freedom force sensor 8F x ,F y Direction range is ±500N, F z Direction range is ±2000N, M x ,M y Direction range is ±20Nm, M z The direction range is ±40Nm, and the accuracy is 0.1%FS; the X-axis direction in this application refers to the direction of the test vehicle, the Y-axis direction refers to the direction perpendicular to the X-axis on the horizontal plane, and the Z-axis direction is the vertical upward direction; F x Indicates the direction pointing to the X axis, M x Indicates the direction of rotation around the X-axis. The six-degree-of-freedom force sensor in this application is mainly used to measure the force in the X-axis direction.

[0093] Preferably, an amplifier 16 and a data collector 17 are installed on the test platform 5. The amplifier 16 is used to amplify the voltage signal of the sensor, and the data collector 17 is used to collect the voltage signal of the amplifier 16 and convert it into a digital signal for transmission to the computer terminal. The output voltage signal range of the amplifier 16 is ±2V; each sensor in this application corresponds to a matching amplifier.

[0094] The data collector in this application uses the USB3106A data collector produced by Altai Company.

[0095] The voltage signal acquisition range of the collector is ±2V, and the maximum acquisition rate is 250Ksps.

[0096] Preferably, the UAV 7 comprises a fuselage 23, on which a main propeller 20, a main propeller motor 21 and a main propeller motor support 22 are arranged; and the landing gear is installed below the fuselage.

[0097] Among them, a tension-torsion sensor 27 is arranged between the main propeller motor 21 and the main propeller motor support 22; the tension-torsion sensor in this application uses the SBT673 customized tension-torsion sensor produced by Guangzhou Sparto Company.

[0098] Preferably, if Figure 4 As shown in the figure, the UAV 7 is optionally provided with a tail thrust propeller 24, a tail thrust propeller motor 25 and a tail thrust propeller motor support 26;

[0099] Accordingly, a tension-torsion sensor 27 is provided between the tail thrust propeller motor 25 and the tail thrust propeller motor support 26. The tension-torsion sensor 27 is used to measure the tension and resistance of the main propeller motor 21 and the tail thrust propeller 24. x Direction range is ±500N, M x Direction range is ±20Nm, accuracy is 0.1%FS;

[0100] Preferably, the drone 7 is also provided with a rotation speed sensor 28, a voltage and current sensor 29, a flight controller 30 and a battery 31;

[0101] The speed sensor 28 is used for the speed of the main propeller motor 21 and the tail propeller 24, with a range of ±50000RPM and an accuracy of 0.5%FS;

[0102] The voltage and current sensor 29 is used to measure the voltage and current input to the main propeller motor 21 and the tail propeller motor 25; the voltage range is ±100V, the current range is ±150A, and the accuracy is 0.2% FS.

[0103] The flight controller 30 is used to provide control signals to the motor, and the battery 31 is used to supply power to the drone 7 .

[0104] The output voltage of the battery 31 is 53.2V, and the capacity is 38Ah.

[0105] Preferably, a pitot tube 19 is installed in front of the center of gravity of the drone 7; the incoming flow velocity in front of the drone is measured by the pitot tube 19. The pitot tube in this application uses the pixhawk px4 differential pitot tube produced by Zhejiang TULE Company.

[0106] A pitot tube support frame 18 is installed just in front of the center of gravity of the UAV 7 , and a pitot tube 19 is installed on the pitot tube support frame 18 .

[0107] The present invention also provides a test method for a multi-rotor UAV, which is implemented by the model ground test device of the UAV.

[0108] The method is to simulate the flight test of a UAV, and specifically includes step 1, calling up the propeller motor PWM signal, flight speed and pitch angle of the UAV to be tested during the actual flight test; and inputting the propeller motor PWM signal into the flight controller 30; that is, before executing the test method of the multi-rotor UAV of the present application, it is necessary to conduct at least one actual flight test to read and record the actual flight test parameters.

[0109] The propeller motor PWM signal corresponds to the speed and pitch angle of the drone. When the speed is 0, the drone is in a hovering state.

[0110] Step 2, adjusting the angle adjustment device 13 so that the pitch angle of the UAV is consistent with the pitch angle during the actual flight test;

[0111] Step 3, controlling the test vehicle 1 to travel at a constant speed according to a set speed;

[0112] Step 4, collecting and recording data from the tension sensor 11, the tension-torsion sensor 27, the rotation speed sensor 28, the voltage and current sensor 29, and the pitot tube 19.

[0113] Example 1: A drone with four main propellers and no tail propeller is selected as the drone to be tested. Figure 3 as shown in .

[0114] The corresponding UAV model ground test device is as follows Figure 1 and Figure 2As shown in the figure, the model ground test device of the UAV includes a drivable and movable test vehicle, a support frame is arranged on the test vehicle, a test platform is arranged on the support frame, and the support frame is a retractable support, and the maximum length that can be extended is 3m; the UAV to be tested is installed on the test platform. The test platform is provided with two slide rails with a length of 800mm and arranged parallel to each other, and the distance between the two slide rails is 600mm;

[0115] The specific values ​​of the propeller motor PWM signal are shown in Table 1 below:

[0116] Table 1 Propeller motor PWM signal

[0117] Flight speed 0m / s 10m / s 15m / s 20m / s Main propeller① 1640.685ms 1571.656ms 1589.366ms 1647.857ms Main propeller② 1512.571ms 1615.072ms 1623.433ms 1490.294ms Main propeller ③ 1522.147ms 1621.184ms 1617.988ms 1505.317ms Main propeller④ 1578.510ms 1668.293ms 1659.383ms 1566.869ms

[0118] Adjust the angle adjustment device 13 so that the pitch angle of the UAV is consistent with the pitch angle during the actual flight test, thereby simulating the pitch angle at different flight speeds;

[0119] Table 2 Pitch angle

[0120] Flight speed 0m / s 10m / s 15m / s 20m / s Pitch Angle 0° 6.9° 10.9° 15.8°

[0121] Power on the drone and control the test vehicle 1 to travel at a constant speed according to the set speed;

[0122] It can be seen from Table 2 that the set speeds are 0 m / s, 10 m / s, 15 m / s, and 20 m / s; the test vehicle 1 travels at a constant speed on the secondary high-grade road surface to simulate the flight speed of the drone.

[0123] The data of the tension sensor 11, the tension-torsion sensor 27, the rotation speed sensor 28, the voltage and current sensor 29, and the pitot tube 19 are collected and recorded.

[0124] Furthermore, during the above-mentioned simulated UAV flight test, the tension sensor 11 can measure the lift of the UAV and predict the lift of the UAV during actual flight; the tension-torsion sensor 27 can measure the tension, resistance, torque of the propeller and the resistance of the UAV, and predict the resistance of the UAV during actual flight.

[0125] The specific implementation process of the tension sensor 11 measuring and predicting the lift of the drone is as follows:

[0126] In the static state, the tension sensor 11 is cleared.

[0127] When the test vehicle 1 travels at a constant speed of 0m / s, 10m / s, 15m / s, and 20m / s, and the main propeller 20 of the UAV rotates at different speeds under the control of the PWM signal described in Table 1, the UAV will generate vertical lift. When the test vehicle 1 travels on a horizontal road, the four tension sensors 11 measure the values ​​of The sum is equal to the lift force L of the drone all As shown in the following formula (I):

[0128]

[0129] The four tension sensors 11 measure the values The specific values ​​of the drone lift are shown in Table 3 below:

[0130] Table 3 Tension sensor measurement values ​​and drone lift (unit: N)

[0131] speed 0m / s 10m / s 15m / s 20m / s Tension sensor① 37.20926 37.44324 37.46624 37.44298 Tension sensor② 37.70324 36.82321 37.54524 36.95869 Tension sensor ③ 37.57971 37.63663 37.53063 37.49355 Tension sensor④ 37.74699 37.72149 37.17973 36.81933 Lift 150.2392 149.6246 149.7218 148.7145

[0132] The lift of the drone is composed of the propeller pull force component in the vertical direction, the propeller resistance force component in the vertical direction and the fuselage resistance. The propeller pull force component in the vertical direction and the propeller resistance force component in the vertical direction are related to the flight speed, propeller speed and pitch angle, and the fuselage resistance is related to the flight speed and pitch angle. Since the speed, propeller speed and pitch angle during the test are the same as those during the actual flight, the measured value of the tension sensor 11 can be used to predict the actual lift L during the actual flight. fly As shown in the following formula (II):

[0133]

[0134] The specific magnitude of the predicted value of the lift is shown in Table 4 below:

[0135] Table 4 Prediction of lift

[0136] speed 0m / s 10m / s 15m / s 20m / s Lift 150.2392 149.6246 149.7218 148.7145

[0137] The specific implementation process of the tension-twist sensor 27 measuring and predicting the resistance of the drone is as follows:

[0138] In a stationary state, the tension-torsion sensor 27 is cleared. When the test vehicle 1 is traveling at a constant speed and the propeller of the drone rotates at a certain speed, the drone will generate horizontal resistance. In a balanced state, the resistance of the drone is mainly composed of the horizontal component of the propeller 20 resistance and the fuselage 23 resistance, which is numerically equal to the horizontal component of the main propeller 20 pulling force.

[0139] When the test vehicle 1 is traveling on a horizontal road, the measured value of the tension-torsion sensor 27 in the X-axis direction is Equal to the pulling force of the main propeller 20 As shown in the following formula (III):

[0140]

[0141] The drag of the drone can be obtained by the following formula (IV):

[0142]

[0143] θ is the angle adjusted by the angle adjustment device 13, which is numerically consistent with the pitch angle during the actual flight process. equal.

[0144] The propeller force and resistance are related to the flight speed, propeller speed, and pitch angle. Since the speed, propeller speed, and pitch angle during the test are the same as those during the actual flight, the measured value of the tension-torsion sensor 27 can be used to predict the actual resistance D of the UAV during actual flight. fly , as shown in the following formula (V):

[0145]

[0146] The specific values ​​of the measured values ​​of the tension-twist sensor 27 in the X-axis direction and the resistance of the drone are shown in Table 5 below:

[0147] Table 5 Measurement values ​​and resistance of the tension-torsion sensor 27 in the X-axis direction (unit: N)

[0148]

[0149]

[0150] Furthermore, during the above-mentioned simulated UAV flight test, the tension-torsion sensor 27, the rotation speed sensor 28, and the voltage and current sensor 29 can measure and record data in real time;

[0151] The tension-torsion sensor 27 measures the value in the Y-axis direction. Equal to the pulling force of the main propeller 20 Pull-twist sensor 27 y Direction measurement value Equal to the torque of the main propeller 20 Speed ​​sensor 28 measurement value Equal to the main propeller 20 speed ω i , the voltage and current sensor 29 measured value Equal to the input motor voltage U i and current I i .

[0152] The torque measurement values ​​of the main propeller 20 are shown in Table 6 below:

[0153] Table 6 Torque measurement values ​​of main propeller 20 (unit: N·m)

[0154] speed 0m / s 10m / s 15m / s 20m / s Torsion sensor① 1.57 1.45 1.15 1.51 Torsion sensor② 1.61 1.87 2.06 1.87 Torsion sensor ③ 1.55 1.32 1.37 1.47 Torsion sensor④ 1.66 1.97 1.86 1.92

[0155] The measured values ​​of the rotation speed sensor 28 are shown in Table 7 below:

[0156] Table 7 Measurement values ​​of speed sensor 28 (unit: rad / s)

[0157] speed 0m / s 10m / s 15m / s 20m / s Speed ​​sensor① 219.12 194.52 183.32 183.78 Speed ​​sensor② 219.16 228.79 229.65 238.28 Speed ​​sensor ③ 219.18 194.62 183.60 183.72 Speed ​​sensor④ 219.16 228.98 229.80 238.20

[0158] The voltage and current sensor 29 measures the value As shown in Table 8 below:

[0159] Table 8 Voltage and current sensor 29 measurement values

[0160]

[0161]

[0162] The power efficiency of the main propeller 20 (power efficiency unit: g / W) is obtained by the following formula (VI):

[0163]

[0164] g is the local gravitational acceleration, the specific value is 9.81m / s 2 .

[0165] The specific values ​​of the power efficiency of the main propeller 20 are shown in Table 9 below:

[0166] Table 9 Power efficiency of main propeller 20 (unit: g / W)

[0167] speed 0m / s 10m / s 15m / s 20m / s Main propeller① 13.65406 14.09494 17.75038 12.559 Main propeller② 13.40773 12.59208 11.86622 12.91415 Main propeller ③ 13.80845 15.55845 15.89039 13.08235 Main propeller④ 12.93944 11.56784 12.68522 12.59544

[0168] The conversion efficiency of the main propeller motor 21 is obtained by the following formula (VII):

[0169]

[0170] The specific values ​​of the conversion efficiency of the main propeller motor 21 are shown in Table 10 below:

[0171] Table 10 Conversion efficiency of main propeller motor 21

[0172] speed 0m / s 10m / s 15m / s 20m / s Main propeller motor① 65.29％ 88.46％ 75.54％ 68.03％ Main propeller motor② 83.68％ 77.89％ 84.96％ 63.51％ Main propeller motor③ 62.92％ 79.68％ 90.67％ 65.39％ Main propeller motor④ 89.29％ 78.20％ 75.92％ 66.91％

[0173] Furthermore, during the above-mentioned simulated UAV flight test, the motor of the UAV is the main power consumption component, and the power consumed by other electronic equipment on the UAV can be ignored. Equal to the motor power on the drone The sum of is obtained by the following formula (eight):

[0174]

[0175] Since the speed, propeller speed, and pitch angle in the simulated UAV flight test are the same as those in the actual flight, the power P required for the UAV to actually fly at a certain speed is all Approximately equal to the power of the drone during the test Obtained by the following formula (IX):

[0176]

[0177] The specific values ​​of the UAV power and the predicted value of power are shown in Table 10 below:

[0178] Table 10 UAV power and power prediction value (unit: W)

[0179] speed 0m / s 10m / s 15m / s 20m / s power 1895.99 1767.39 1676.31 2206.08

[0180] The flight time of the UAV (unit: hours) is obtained by the following formula (10):

[0181]

[0182] Q W The capacity of battery 31 (unit: Wh)

[0183] The specific values ​​of the UAV flight time are shown in Table 11 below:

[0184] Table 11 UAV flight time (unit: hours)

[0185] speed 0m / s 10m / s 15m / s 20m / s Flight time 1.07 1.14 1.21 0.92

[0186] The UAV range (unit: kilometers) is obtained by the following formula (XI):

[0187] x=Vt (11)

[0188] V is the flight speed, which is equal to the average value of the incoming flow speed measured by the pitot tube 19.

[0189] The specific values ​​of the UAV range are shown in Table 12 below:

[0190] Table 12 UAV range (unit: kilometers)

[0191] speed 0m / s 10m / s 15m / s 20m / s voyage 0.00 41.18 65.12 65.98

[0192] Verify the above lift: In the balanced state, the lift of the drone is the same as its own weight. The weight of the drone used in the test is 150N. The relative error calculation formula for lift measurement is:

[0193]

[0194] The specific verification results are shown in the following table:

[0195] Drone speed 0m / s 10m / s 15m / s 20m / s Lift relative error σ 0.16％ 0.25％ 0.19％ 0.86％

[0196] The relative error is within the allowable range of 1%, which means the measurement result is accurate.

[0197] The UAV resistance, main propeller force efficiency and UAV power in the above-mentioned embodiment 1 were verified through wind tunnel experiments, and it was found that the results were basically consistent with the results in the above-mentioned embodiment 1, with an error within 1%.

[0198] The time consumed in Example 1 is basically the same as that in the wind tunnel experiment, but the operation in Example 1 is simple, and no special training is required for the operator. Only one person is required to complete the entire experimental process of fixing the drone, driving to collect data, and summarizing the data to obtain the experimental results. The scheme in Example 1 can be used to conduct repeated experiments on drones of different models and sizes, which has greater practical value.

[0199] Example 2: A drone with four main propellers and a tail propeller is selected as the drone to be tested. Figure 4 as shown in .

[0200] The corresponding UAV model ground test device is as follows Figure 1 and Figure 2 As shown in the figure, the model ground test device of the UAV includes a drivable and movable test vehicle, a support frame is arranged on the test vehicle, a test platform is arranged on the support frame, the support frame is a retractable support, and the maximum length that can be extended is 3m; the UAV to be tested is installed on the test platform. The test platform is provided with two slide rails with a length of 800mm and arranged parallel to each other, and the distance between the two slide rails is 600mm.

[0201] The specific values ​​of the propeller motor PWM signal are shown in Table 13 below:

[0202] Table 13 Propeller motor PWM signal

[0203]

[0204]

[0205] Adjust the angle adjustment device 13 so that the pitch angle of the drone is 0.

[0206] Power on the drone and control the test vehicle 1 to travel at a constant speed according to the set speed;

[0207] As can be seen from Table 2, the set speeds are 0m / s, 10m / s, 15m / s, and 20m / s; the test vehicle 1 travels at a constant speed on the secondary high-grade road, simulating the flight speed of the drone.

[0208] The data of the tension sensor 11, the tension-torsion sensor 27, the rotation speed sensor 28, the voltage and current sensor 29, and the pitot tube 19 are collected and recorded.

[0209] Furthermore, during the above-mentioned simulated UAV flight test, the six-degree-of-freedom force sensor 8 can measure the resistance of the UAV, the tension sensor 11 can measure the lift of the UAV and predict the lift of the UAV during actual flight; the tension-torsion sensor 27 can measure the tension, resistance, torque of the main propeller and the resistance of the UAV, and the tension-torsion sensor 27 can measure the tension and torque of the tail thrust propeller.

[0210] The specific implementation process of the six-degree-of-freedom force sensor 8 measuring and predicting the drag of the drone is as follows:

[0211] When the test vehicle 1 is traveling at a constant speed, the main propeller is rotating at a certain speed, and the tail propeller is not working, the drone 7 will generate resistance in the opposite direction of the speed. Under the action of the resistance, the multi-rotor drone will move backward along the slide rail 9 until it touches the front link 14 and contacts the six-degree-of-freedom force sensor 8. Ignoring the friction resistance between the slide rail 9 and the slider 10, the X-axis measurement value T of the six-degree-of-freedom force sensor 8 is si,x The only measurement of drone resistance, that is, the total resistance of the drone, is shown in the following formula (XII):

[0212] D all =T six,x (twelve)

[0213] The drag of the drone is composed of the main propeller drag and the fuselage drag. The main propeller drag is related to the flight speed and propeller speed, and the fuselage drag is related to the flight speed. Since the speed and propeller speed during the test are the same as those during actual flight, it can be considered that the measurement value of the six-degree-of-freedom force sensor 8 in the X-axis direction is approximately equal to the real drag D during actual flight. fly , as shown in the following formula (XIII):

[0214] D fly =D all =T six,x (Thirteen)

[0215] The specific value of the UAV resistance and the predicted value of the resistance are shown in Table 14 below:

[0216] Table 14 UAV resistance value and predicted resistance value (unit: N)

[0217] Flight speed 0m / s 10m / s 15m / s 20m / s resistance 0 11.90 18.39 25.30

[0218] The specific implementation process of the tension sensor 11 measuring and predicting the lift of the drone is as follows:

[0219] Drone lift L all Obtained by the following formula (1):

[0220]

[0221] The actual lift L during actual flight is predicted using the measured value of the tension sensor 11 fly As shown in the following formula (II):

[0222]

[0223] The four tension sensors 11 measure the values The specific value and predicted value of the lift of the UAV are shown in Table 15:

[0224] Table 15 Tension sensor measurement values ​​and drone lift (unit: N)

[0225] speed 0m / s 10m / s 15m / s 20m / s Tension sensor① 37.06 37.48 37.23 36.97 Tension sensor② 36.83 37.10 37.17 37.28 Tension sensor ③ 36.88 37.74 37.55 37.23 Tension sensor④ 37.61 36.82 37.58 37.43 Drone lift 148.39 149.15 149.53 148.92

[0226] Among them, the specific implementation process of the torque sensor measuring the tension and torque of the tail propeller of the drone is as follows:

[0227] In the static state, the tension-torsion sensor 27 is cleared. When the test vehicle 1 is moving at a constant speed and the main propeller 20 and the tail propeller 24 of the UAV are rotating at a certain speed, the tail propeller 24 will generate a pulling force opposite to the speed direction and a torque opposite to the rotation direction. Among them, the measurement value F of the tension-torsion sensor 27 in the X-axis direction is two,x Equal to the pulling force T of the tail propeller 24 tai , the tension and torsion sensor 27 is x Direction measurement value M two,x Equal to the torque Q of the tail thrust propeller 24 tail , as shown in the following formula (fourteen):

[0228]

[0229] The specific values ​​of the tension and torque of the tail thrust propeller 24 measured by the tension-torsion sensor 27 are shown in Table 16 below:

[0230] Table 16 Thrust and torque of tail propeller 24

[0231] speed 0m / s 10m / s 15m / s 20m / s Tension(N) 0 13.93 21.26 26.92 Torque (N·m) 0 0.92 1.12 1.74

[0232] Furthermore, during the above-mentioned simulated UAV flight test, the tension-torsion sensor 27, the rotation speed sensor 28, and the voltage and current sensor 29 can measure and record data in real time;

[0233] The tension-torsion sensor 27 measures the value in the Y-axis direction. Equal to the pulling force of the main propeller 20 Speed ​​sensor 28 measurement value = equal to the speed ω of the main propeller 20 (i = 1, 2, 3, 4 and the tail propeller 24 (i = 5) i (i=1,2,3,4, voltage and current sensor 29 measured value =Equal to the voltage and current U input to the main propeller motor 21 and the tail propeller motor 26 i ,I i (i=1,2,3,4,5).

[0234] The measured values ​​of the pulling force of the main propeller 20 are shown in Table 17 below:

[0235] Table 17 Measured values ​​of thrust of main propeller 20 (unit: N)

[0236]

[0237]

[0238] The torque measurement values ​​of the main propeller 20 are shown in Table 18 below:

[0239] Table 18 Torque measurement values ​​of main propeller 20 (unit: N·m)

[0240] speed 0m / s 10m / s 15m / s 20m / s Main propeller① 1.66 0.91 0.77 0.57 Main propeller② 1.33 1.55 1.35 0.93 Main propeller ③ 1.64 0.86 0.70 0.58 Main propeller④ 1.39 1.58 1.38 1.17

[0241] The specific rotation speed measurement values ​​of the main propeller 20 and the tail thrust propeller 24 are shown in Table 19 below:

[0242] Table 19 Rotational speed measurement values ​​of the main propeller 20 and the tail propeller 24 (unit: rad / s)

[0243] speed 0m / s 10m / s 15m / s 20m / s Main propeller① 275.17 205.88 187.32 155.31 Main propeller② 246.73 263.80 242.40 195.84 Main propeller ③ 252.00 265.68 245.40 222.39 Main propeller④ 273.61 200.64 178.67 140.26 Tail pusher propeller 0 251.865 313.84 412.28

[0244] The voltage and current sensor 29 measures the value As shown in Table 20 below:

[0245] Table 20 Voltage and current sensor 29 measurement values

[0246]

[0247] The power efficiency of the main propeller 20 (power efficiency unit: g / W) is obtained by the following formula (VI):

[0248]

[0249] g is the local gravitational acceleration, the specific value is 9.81m / s 2 .

[0250] The conversion efficiency of the main propeller motor 21 is obtained by the following formula (VII):

[0251]

[0252] The force efficiency (force efficiency unit: g / W) of the tail thrust propeller 24 is obtained by the following formula (15):

[0253]

[0254] g is the local gravitational acceleration, the specific value is 9.81m / s 2 .

[0255] The conversion efficiency of the tail propeller motor 25 is obtained by the following formula (16):

[0256]

[0257] The power efficiency calculation results of the main propeller 20 and the tail thrust propeller 24 are shown in Table 21 below:

[0258] Table 21 Power efficiency of main propeller 20 and tail propeller 24 (unit: g / W)

[0259] speed 0m / s 10m / s 15m / s 20m / s Main propeller① 8.53 20.73 27.36 44.09 Main propeller② 11.90 9.25 11.67 20.88 Main propeller ③ 9.21 16.52 22.53 29.87 Main propeller④ 10.23 12.15 15.40 23.72 Tail pusher propeller / 6.13 6.17 3.83

[0260] The calculation results of the conversion efficiency (unit: %) of the main propeller motor 21 and the tail propeller motor 25 are shown in the following Table 22:

[0261] Table 22 Conversion efficiency of main propeller motor 21 and tail propeller motor 25

[0262] speed 0m / s 10m / s 15m / s 20m / s Main propeller① 86.69 96.27 86.16 79.37 Main propeller② 77.82 83.53 79.77 89.83 Main propeller ③ 76.54 43.16 41.13 43.00 Main propeller④ 93.34 82.00 88.03 73.21 Tail pusher propeller / 62.83 54.23 37.20

[0263] Furthermore, during the above-mentioned simulated UAV flight test, the motor of the UAV is the main power consumption component, and the power consumed by other electronic equipment on the UAV can be ignored. Equal to the motor power on the drone The sum of is obtained by the following formula (XVII):

[0264]

[0265] Since the speed, propeller speed, and pitch angle in the simulated UAV flight test are the same as those in the actual flight, the power P required for the UAV to actually fly at a certain speed is all Approximately equal to the power of the drone during the test Obtained by the following formula (18):

[0266]

[0267] The specific values ​​of the UAV power and the predicted value of power are shown in Table 23 below:

[0268] Table 23 UAV power and power prediction value (unit: W)

[0269] speed 0m / s 10m / s 15m / s 20m / s power 1895.99 1968.95 1923.48 2766.56

[0270] The flight time of the UAV (unit: hours) is obtained by the following formula (10):

[0271]

[0272] Q W The capacity of battery 31 (unit: Wh)

[0273] The specific values ​​of the UAV flight time are shown in Table 24 below:

[0274] Table 24 UAV flight time (unit: hours)

[0275] speed 0m / s 10m / s 15m / s 20m / s Flight time 1.07 1.03 1.05 0.73

[0276] The UAV range (unit: kilometers) is obtained by the following formula (XI):

[0277] x=Vt (11)

[0278] V is the flight speed, which is equal to the average value of the incoming flow speed measured by the pitot tube 19.

[0279] The specific values ​​of the UAV range are shown in Table 25 below:

[0280] Table 25 UAV range (unit: kilometers)

[0281] speed 0m / s 10m / s 15m / s 20m / s voyage 0.00 36.96 56.75 52.61

[0282] The present invention has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, the present invention may be subjected to a variety of substitutions and improvements, all of which fall within the scope of protection of the present invention.

Claims

1. A model ground test device for an unmanned aerial vehicle, characterized in that: The device comprises a drivable and movable test vehicle (1), a support frame (2) is arranged on the test vehicle (1), and a test platform (5) is arranged on the support frame (2); The support frame (2) is a retractable support frame; The unmanned aerial vehicle (7) to be tested is installed on the test platform (5).

2. The model ground test device of the unmanned aerial vehicle according to claim 1, characterized in that: The test platform (5) is provided with two slide rails (9) arranged parallel to each other; the length direction of the slide rails (9) is consistent with the travel direction of the test vehicle (1). The slide rail (9) is provided with a slider (10) capable of reciprocatingly sliding along the length direction thereof. A tension sensor (11) is installed on the slider (10), and the lift of the drone is measured by the tension sensor (11); The test platform (5) is also provided with an angle adjustment device (13), through which the angle between the plane of the drone and the horizontal plane is adjusted to simulate the pitch angle of the drone in actual flight; The drone is mounted on the angle adjustment device (13).

3. The model ground test device of the unmanned aerial vehicle according to claim 2, characterized in that: Two angle adjustment devices (13) are provided, and one angle adjustment device (13) is provided on each slide rail (9); The angle adjustment device (13) is connected to the slider (10) via a tension sensor (11), and two tension sensors (11) and two sliders (10) are correspondingly arranged below each angle adjustment device (13).

4. The model ground test device of the unmanned aerial vehicle according to claim 3, characterized in that: A front connecting rod (14) and a rear connecting rod (15) are connected between the two angle adjustment devices (13); the two angle adjustment devices (13) move synchronously with the front connecting rod (14) and the rear connecting rod (15); On the test platform (5), a six-degree-of-freedom force sensor (8) is also arranged between the front connecting rod (14) and the rear connecting rod (15).

5. The model ground test device of the unmanned aerial vehicle according to claim 2, characterized in that: An amplifier (16) and a data collector (17) are installed on the test platform (5). The amplifier (16) is used to amplify the voltage signal of the sensor, and the data collector (17) is used to collect the voltage signal of the amplifier (16) and convert it into a digital signal for transmission to a computer terminal.

6. The model ground test device of the unmanned aerial vehicle according to claim 1, characterized in that: The unmanned aerial vehicle (7) comprises a fuselage (23), on which a main propeller (20), a main propeller motor (21) and a main propeller motor support (22) are arranged; Wherein, a tension-torsion sensor (27) is arranged between the main propeller motor (21) and the main propeller motor support (22); Preferably, the UAV (7) is optionally provided with a tail-thrust propeller (24), a tail-thrust propeller motor (25) and a tail-thrust propeller motor support (26); Correspondingly, a tension-torsion sensor (27) is provided between the tail thrust propeller motor (25) and the tail thrust propeller motor support (26).

7. The model ground test device of the unmanned aerial vehicle according to claim 6, characterized in that: The drone (7) is also provided with a rotation speed sensor (28), a voltage and current sensor (29), a flight controller (30) and a battery (31); Wherein, the rotation speed sensor (28) is used for the rotation speed of the main propeller motor (21) and the tail thrust propeller (24); The voltage and current sensor (29) is used to measure the voltage and current input to the main propeller motor (21) and the tail propeller motor (25); The flight controller (30) is used to provide a control signal to the motor, and the battery (31) is used to supply power to the drone (7).

8. The model ground test device of the unmanned aerial vehicle according to claim 6, characterized in that: A pitot tube (19) is installed just in front of the center of gravity of the drone (7); the incoming flow velocity in front of the drone is measured by the pitot tube (19).

9. A test method for a multi-rotor drone, characterized in that: The method is implemented by a model ground test device of the UAV as described in any one of claims 1-8.

10. The test method of a multi-rotor UAV according to claim 9, characterized in that: The method comprises the following steps: Step 1, retrieve the propeller motor PWM signal, flight speed and pitch angle of the unmanned aerial vehicle to be tested during the actual flight test; and input the propeller motor PWM signal into the flight controller (30); Step 2, adjusting the angle adjustment device (13) so that the pitch angle of the UAV is consistent with the pitch angle during the actual flight test; Step 3, controlling the test vehicle (1) to travel at a constant speed according to a set speed; Step 4, collecting and recording data from the tension sensor (11), the tension-torsion sensor (27), the rotation speed sensor (28), the voltage and current sensor (29), and the pitot tube (19).

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