An unmanned aerial vehicle real-time oil quantity detection method and system, and unmanned aerial vehicle

Abstract

The application discloses a kind of unmanned aerial vehicle real-time oil quantity detection system, method and unmanned aerial vehicle, system includes: oil tank, air pressure sensor, pressure hose, stop valve, air pressure sensor is arranged at the top outside of oil tank, the first input end of air pressure sensor is connected to the one end of pressure hose connection, pressure hose is arranged in oil tank and extends to the bottom of oil tank, the other end of pressure hose is provided with stop valve, the second input end of air pressure sensor is placed above the liquid level of oil tank or in the atmospheric environment in cabin, air pressure sensor is connected with the communication connection of the flight attitude reference system of unmanned aerial vehicle.It is realized when the maneuvering action of unmanned aerial vehicle flight process is made, and the oil tank oil quantity of unmanned aerial vehicle is accurately measured in real time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of unmanned aerial vehicles, and more particularly to an unmanned aerial vehicle real-time oil quantity detection method and system and unmanned aerial vehicle. BACKGROUND

[0002] In recent years, with the rapid development of unmanned aerial vehicle technology, unmanned aerial vehicles have been widely used in information acquisition, high-altitude operation and other aspects. At present, unmanned aerial vehicles are mainly divided into two categories according to the power source. One is an electric unmanned aerial vehicle, including an unmanned aerial vehicle using battery power supply technology and an unmanned aerial vehicle using solar new energy power supply technology. This type of unmanned aerial vehicle does not need an engine to provide power and can be driven by an electric motor only. It has the advantages of being green, environmentally friendly and easy to maintain, but its endurance and wind resistance are poor. The other is an oil-powered unmanned aerial vehicle. This type of unmanned aerial vehicle needs an engine to provide cruising power, including a gasoline engine and a heavy oil engine. It has the characteristics of long endurance and strong wind resistance.

[0003] Most traditional small oil-powered long-endurance unmanned aerial vehicles do not have an oil quantity sensor. The main reasons are as follows:

[0004] 1) Due to the weight limit of the aircraft, various types of on-board sensors should be miniaturized and lightened as much as possible. However, there is no special oil quantity sensor for small unmanned aerial vehicles at present.

[0005] 2) The liquid level measurement sensor used in the traditional automatic control field is difficult to achieve good measurement accuracy on a small unmanned aerial vehicle. During flight, the unmanned aerial vehicle makes attitude changes, acceleration and deceleration, and other dynamic actions. The liquid level will change dramatically and shake. The error of the traditional liquid level measurement device is large, and it is difficult to obtain the accurate oil storage quantity of the aircraft by measuring the liquid level height. The false oil quantity information returned to the ground control personnel may cause the pilot and ground station operator to fail to adjust the flight plan according to the accurate oil consumption, which may seriously affect the flight safety.

[0006] The prior art discloses an unmanned aerial vehicle oil tank low oil quantity detection device and method. The prior art includes a control circuit and a proximity switch measurement sensor. The proximity switch measurement sensor is installed at the low oil quantity position of the side wall of the oil tank. The sensing probe is located in the oil tank, and the signal output end is located outside the oil tank, which is used to detect the oil position and output a signal. The control circuit includes a power supply circuit, a sensor signal sampling circuit and an oil quantity state reporting circuit. The power supply circuit supplies power to the proximity switch measurement sensor and the sensor signal sampling circuit and the oil quantity state reporting circuit. The sensor signal sampling circuit samples and analyzes the output signal of the proximity switch measurement sensor and outputs it through the oil quantity state reporting circuit. The traditional fixed sensor probe used in this technical solution cannot accurately measure the oil quantity when the unmanned aerial vehicle makes attitude changes, acceleration and deceleration and other dynamic actions during flight. SUMMARY

[0007] The present application is to overcome the above-mentioned prior art cannot accurately measure the oil quantity when the unmanned aerial vehicle makes a maneuvering action during flight, provide a kind of unmanned aerial vehicle real-time oil quantity detection method, system and unmanned aerial vehicle, can accurately measure the oil quantity when the unmanned aerial vehicle makes a maneuvering action during flight.

[0008] The primary object of the present application is to solve the above technical problems, and the technical scheme of the present application is as follows:

[0009] The first aspect of the present application provides a kind of unmanned aerial vehicle real-time oil quantity detection system, comprising: oil tank, air pressure sensor, pressure hose, stop valve, air pressure sensor is arranged at the top of oil tank outside, the first input end of air pressure sensor is connected with the one end of pressure hose, pressure hose is arranged in oil tank and extends to the bottom of oil tank, the other end of pressure hose is provided with stop valve, the second input end of air pressure sensor is placed above the liquid level of oil tank or in the atmospheric environment of cabin, air pressure sensor is connected with the communication of the attitude reference system of unmanned aerial vehicle.

[0010] Further, the attitude reference system includes: inertial measurement unit, magnetometer, the inertial measurement unit is used to measure oil tank acceleration, and the magnetometer is used to measure heading angle.

[0011] Further, the oil tank is the oil tank of preset three-dimensional digital model.

[0012] Further, the stop valve is gravity stop valve, the gravity stop valve includes valve body, the inside of valve body is equipped with upper and lower communication hole section, wherein, the top of lower hole section is equipped with movable valve core, the bottom of lower hole section is equipped with oil inlet, the oil inlet is equipped with locking component, and elastic member is installed between locking component and valve core.

[0013] Further, the hole diameter of lower hole section is greater than the hole diameter of upper hole section, the valve core is spherical valve core, and the diameter of valve core is less than the hole diameter of lower hole section and greater than the hole diameter of upper hole section.

[0014] Further, the elastic member is spring.

[0015] Further, locking component is fixedly connected with oil inlet by screw thread.

[0016] The second aspect of the present application provides a kind of unmanned aerial vehicle real-time oil quantity detection method, the method is applied to the unmanned aerial vehicle real-time oil quantity detection system, and the characterized in that, comprising the following steps: obtaining the differential pressure data collected by air pressure sensor;

[0017] Using differential pressure data, calculating oil level height according to preset differential pressure balance formula;

[0018] The oil quantity in the oil tank is obtained according to the oil tank liquid level and the attitude quaternion of the oil tank output by the attitude and position reference system.

[0019] Further, the differential pressure balance formula is:

[0020]

[0021] wherein, is the differential pressure between the pressure in the pilot hose and the local atmospheric pressure, is the oil tank acceleration, when in a static state, is the fuel density in the oil tank.

[0022] Further, when calculating the oil tank liquid level, the high-frequency sampling values of the oil tank acceleration and the differential pressure between the pressure in the pilot hose and the local atmospheric pressure are filtered by using a digital filter to retain the low-frequency part signals, and the filtered , is used to calculate the liquid level.

[0023] Further, the digital filter is a finite-time impulse response filter.

[0024] Further, the oil quantity in the oil tank is obtained according to the oil tank liquid level and the attitude quaternion of the oil tank output by the attitude and position reference system, and the specific calculation formula is:

[0025]

[0026] wherein, is the oil quantity in the oil tank, represents the liquid surface area corresponding to the liquid surface with a height of when the oil tank is in the attitude represented by the attitude quaternion .

[0027] Further, the attitude quaternion of the oil tank is given by the attitude and position reference system of the airborne flight controller.

[0028] The third aspect of the present application provides a UAV, which adopts the real-time oil quantity detection system of the UAV.

[0029] Compared with the prior art, the technical scheme of the present application has the beneficial effects that:

[0030] This invention constructs a real-time fuel level detection system for UAVs by using a fuel tank, a pressure sensor, a pressure hose, a shut-off valve, and an attitude reference system for the UAV. The pressure sensor detects the pressure and obtains the pressure difference between the pressure inside the pressure hose and the local atmospheric pressure. Combined with the acceleration of the fuel tank and the fuel density inside the tank, the fuel level is obtained. The attitude parameters of the fuel tank provided by the attitude reference system are used to calculate the fuel level in the tank. This enables real-time and accurate measurement of the fuel level in the UAV's fuel tank during flight maneuvers. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of a real-time fuel level detection system for unmanned aerial vehicles (UAVs) according to an embodiment of the present invention.

[0032] Figure 2 This is a flowchart of a real-time fuel level detection method for unmanned aerial vehicles (UAVs) according to an embodiment of the present invention.

[0033] Figure 3 This is a cross-sectional structural diagram of a gravity shut-off valve provided in an embodiment of the present invention.

[0034] Figure 4 This is a three-dimensional structural diagram of a gravity shut-off valve provided in an embodiment of the present invention. Detailed Implementation

[0035] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0036] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0037] Example 1

[0038] like Figure 1 As shown, the first aspect of the present invention provides a real-time fuel level detection system for a UAV, comprising: a fuel tank 1, a pressure sensor 2, a pressure hose 3, and a shut-off valve 4. The pressure sensor 2 is disposed on the top outer side of the fuel tank 1. The first input end of the pressure sensor 2 is connected to one end of the pressure hose 3. The pressure hose 3 is disposed inside the fuel tank 1 and extends to the bottom of the fuel tank 1. The other end of the pressure hose 3 is provided with a shut-off valve 4. The second input end of the pressure sensor 2 is placed above the fuel level in the fuel tank 1 or in the atmospheric environment inside the cabin. The pressure sensor 2 is communicatively connected to the attitude reference system of the UAV.

[0039] The application constructs a real-time oil quantity detection system of the unmanned aerial vehicle by the oil tank 1, the air pressure sensor 2, the pressure leading hose 3, the stop valve 4 and the flight attitude reference system of the unmanned aerial vehicle, detects the air pressure by the air pressure sensor 2, and then obtains the pressure difference between the pressure in the pressure leading hose 3 and the local atmospheric pressure, obtains the acceleration of the oil tank 1 by the flight attitude reference system, obtains the liquid level height of the oil tank 1 by combining the fuel density in the oil tank 1 , and gives the attitude quaternion of the oil tank 1 by combining the flight attitude reference system (AHRS) The oil quantity in the oil tank is calculated. The application realizes real-time and accurate measurement of the oil quantity in the oil tank of the unmanned aerial vehicle when the unmanned aerial vehicle makes a maneuvering action in the flight process, and further calculates the oil consumption level and the remaining safe range according to the oil quantity in the oil tank, which provides a technical guarantee for the flight safety.

[0040] It should be noted that in one specific embodiment, the air pressure sensor 2 can be a micro differential pressure sensor.

[0041] Further, the flight attitude reference system comprises an inertial measurement unit and a magnetometer, the inertial measurement unit is used for measuring the acceleration of the oil tank, and the magnetometer is used for measuring the heading angle.

[0042] It should be noted that the inertial measurement unit is used for measuring the acceleration of the oil tank, and the magnetometer is used for measuring the heading angle, and the heading angle is used for determining the flight attitude of the unmanned aerial vehicle. The oil tank 1 is a preset three-dimensional digital model oil tank.

[0043] Further, as shown in Figures 3-4 The stop valve 4 is a gravity stop valve, the gravity stop valve comprises a valve body 401, the valve body 401 is internally provided with an upper and lower communicating hole section, wherein the top of the lower hole section is provided with a movable valve core 402, the bottom of the lower hole section is provided with an oil inlet 403, the oil inlet 403 is internally provided with a locking part 404, and the locking part 404 and the valve core 402 are installed with an elastic element 405.

[0044] It should be noted that in a specific embodiment, the top end of the upper hole section of the gravity cut-off valve is communicated with the pressure leading hose 3 of the detection system, the hole diameter of the lower hole section is larger than that of the upper hole section, the top of the lower hole section is provided with a movable valve core 402, the valve core 402 is a spherical valve core, the diameter of the valve core 402 is smaller than the hole diameter of the lower hole section and larger than the hole diameter of the upper hole section, the bottom of the lower hole section is provided with an oil inlet 403, the oil inlet 403 is provided with a locking part 404, an elastic element 405 is arranged between the locking part 404 and the valve core 402, the elastic element 405 can be a spring, when the airplane is stably flying or is parked on the ground, the gravity cut-off valve sinks to the bottom of the oil tank, at this time, the elastic element 405 lifts the valve core 402, but the elastic force of the elastic element 405 is not enough to lift the valve core 402 to the bottom end surface of the upper hole section of the valve body 401, so the upper and lower hole sections are communicated, the oil can enter the valve body 401 and the pressure leading hose 3 from the oil inlet, and the air pressure sensor 2 can calculate the oil level from the air pressure in the pressure leading hose 3.

[0045] In the present application, when the airplane is doing a maneuvering flight, the motion acceleration and attitude of the airplane will change, the cut-off valve 4 of the oil tank 1 is heavy, the pressure leading hose 3 and the cut-off valve 4 will sink to the bottom of the oil tank 1 under the joint action of the gravitational acceleration and the inertial acceleration, and at the same time, the cut-off valve 4 is opened under the action of the acceleration.

[0046] More specifically, when the unmanned plane is doing a maneuvering action, especially after diving and pulling up, at this time, the unmanned plane is in an overweight state, the working process of the valve core 402 of the gravity cut-off valve is the same as that when the airplane is stably flying or is parked on the ground, that is, the elastic force of the elastic element 405 is not enough to push the valve core 402 to the bottom end surface of the upper hole section, at this time, the liquid level detection can be carried out.

[0047] When the airplane is in a weightless state, the cut-off valve 4 is closed, so as to prevent the pressure leading hose 3 from leading the low air pressure in the high altitude when it is not deep enough below the liquid level.

[0048] More specifically, when the unmanned plane is flying, the nose is pushed down, at this time, the unmanned plane is in a weightless state, at this time, the elastic force of the elastic element 405 is enough to push the valve core 402 to the bottom end surface of the upper hole section, so as to cut off the gravity cut-off valve, when the whole airplane is in a weightless state and especially when the oil is also in a weightless state, the situation that the gravity cut-off valve does not immerse below the liquid level and leads the low air pressure in the high altitude can be avoided.

[0049] Embodiment 2

[0050] Based on the above detection system, the second aspect of the present application provides a real-time oil quantity detection method for unmanned aerial vehicle, which is applied to the unmanned aerial vehicle real-time oil quantity detection system, and characterized in that the method comprises the following steps: S1, obtaining the differential pressure data collected by the air pressure sensor 2;

[0051] It should be noted that when the bottom of the pressure lead hose 3 is at the bottom of the oil tank 1, due to the height difference between the oil tank 1 liquid level and the stop valve 4, the liquid level pressure difference makes the air in the pressure lead hose 3 compressed, and the pressure increases, when the liquid level pressure and the pressure in the pressure lead hose 3 reach balance, the pressure difference balance formula is satisfied:

[0052] Among them, is the pressure difference between the pressure in the pressure lead hose 3 and the local atmospheric pressure, the two input ends of the air pressure sensor 2 measure the pressure in the pressure lead hose, the pressure of the local atmosphere (i.e. the air pressure above the oil tank liquid level or the internal atmosphere pressure of the cabin), is the acceleration of the oil tank, which can be calculated by the inertial measurement unit, when in a stationary state, ; is the fuel density in the oil tank 1, which can be calibrated before take-off.

[0053] S2, calculating the oil tank 1 liquid level height according to the preset pressure difference balance formula by using the pressure difference data;

[0054] It should be noted that the oil tank 1 liquid level height can be calculated by the above calculation formula, due to the influence of the inertial measurement unit on the body vibration, the oil tank 1 acceleration given by the inertial measurement unit has high frequency noise, in addition, the liquid surface will also make the pressure difference fluctuate greatly when the body moves, therefore, when calculating , a digital filtering technology is used to filter the high frequency sampling values of and with a finite time impulse response filter FIR, only the low frequency part of the signal is retained, and the measurement value error caused by the instantaneous overloading, weight loss or attitude change of the aircraft is shielded by using the filtered values to calculate the liquid level height.

[0055] S3, calculating the oil quantity in the oil tank 1 according to the oil tank 1 liquid level height and the attitude quaternion of the oil tank output by the attitude and position reference system.

[0056] It should be noted that after the oil tank 1 liquid level height is calculated, the oil quantity can be calculated according to the attitude of the aircraft, the three-dimensional digital model of the oil tank 1, in a specific embodiment, the oil quantity in the oil tank can be calculated by the following formula :

[0057]

[0058] Among them, The oil tank is in a posture quaternion represents the posture of the oil tank in a posture quaternion represents the posture of the oil tank in a posture quaternion The liquid surface area corresponding to the liquid surface of the oil tank 1 in the posture quaternion The posture quaternion is given by the attitude and heading reference system of the airborne flight controller.

[0059] Embodiment 3

[0060] Based on the above detection system and method, the third aspect of the present application provides a UAV adopting the UAV real-time oil quantity detection system.

[0061] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only illustrative, for example, the division of the units is only a logical function division, and actual implementation can have another division mode, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the various components shown or discussed can be through some interface, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0062] The units described above as separate components can or can not be physically separated, and the components shown as units can or can not be physical units; they can be located in one place or distributed on multiple network units; some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0063] In addition, each functional unit in each embodiment of the present application can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be realized in the form of hardware or hardware plus software functional unit.

[0064] Those skilled in the art can understand that all or part of the steps of the above method embodiments can be completed by program instruction related hardware, and the foregoing program can be stored in a computer readable storage medium, and the program executes the steps including the above method embodiments when executed; and the foregoing storage medium includes: mobile storage device, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disc or optical disc and various storage program codes.

[0065] Alternatively, the above-mentioned integrated unit of the present application, if realized in the form of a software function module and sold or used as an independent product, can also be stored in a computer-readable storage medium. Based on such an understanding, the technical solutions of the embodiments of the present application can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: mobile storage devices, ROM, RAM, magnetic disks or optical disks, and various media that can store program codes.

[0066] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A drone real-time fuel level detection system, characterized in that, The system comprises an oil tank, a gas pressure sensor, a pressure leading hose, and a stop valve. The stop valve is a gravity stop valve, which comprises a valve body (401) with an upper and lower hole section. When the UAV is in stable flight, on the ground, or in an overweight state, the gravity stop valve sinks to the bottom of the oil tank and opens, at which time the upper and lower hole sections are connected, and oil can enter the valve body (401) and the pressure leading hose from the oil inlet (403). When the UAV is in a weightless state, the gravity stop valve is closed, avoiding the situation where the gravity stop valve is not immersed below the oil level and high-altitude low-pressure is introduced. The attitude reference system comprises an inertial measurement unit and a magnetometer.

2. The unmanned aerial vehicle real-time fuel detection system of claim 1, wherein, The oil tank is a pre-set three-dimensional digital model.

3. The unmanned aerial vehicle real-time fuel detection system of claim 1, wherein, The hole diameter of the lower hole section is larger than that of the upper hole section, the valve core is a spherical valve core, and the diameter of the valve core is smaller than that of the lower hole section and larger than that of the upper hole section.

4. The unmanned aerial vehicle real-time fuel detection system of claim 1, wherein, The elastic member (405) is a spring.

5. The unmanned aerial vehicle real-time fuel level detection system of claim 1, wherein, The locking component (404) is fixedly connected with the oil inlet (403) by threads.

6. The unmanned aerial vehicle real-time fuel detection system of claim 1, wherein, The system comprises the following steps:

7. A method for real-time fuel quantity detection of a UAV, the method being applied to the real-time fuel quantity detection system of any one of claims 1-6, characterized in that, Obtaining the pressure difference data collected by the gas pressure sensor; Using the pressure difference data to calculate the oil tank level according to a pre-set pressure difference balance formula; Obtaining the oil quantity in the oil tank according to the oil tank level and the attitude quaternion of the oil tank output by the attitude reference system. The pressure difference balance formula is:

8. The unmanned aerial vehicle real-time oil detection method of claim 7, wherein, The digital filter is a finite time impulse response filter. wherein, is the pressure difference between the pressure in the induction hose and the local atmospheric pressure, is the acceleration of the tank when at rest, ; is the density of the fuel in the tank; is the level height of the tank. 9.The unmanned aerial vehicle real-time oil detection method of claim 8, wherein, In calculating the oil tank level, the acceleration of the oil tank is first filtered by a digital filter , the pressure difference between the pressure in the pressure lead hose and the local atmospheric pressure of the high frequency sampling value, the low frequency part of the signal is retained, and the filtered 、 is used to calculate the level. 10.The unmanned aerial vehicle real-time oil detection method of claim 9, wherein, Obtaining the oil quantity in the oil tank according to the oil tank level and the attitude quaternion of the oil tank output by the attitude reference system, and the specific calculation formula is:

11. The unmanned aerial vehicle real-time fuel detection method of claim 8, wherein, The UAV real-time oil quantity detection system of any one of claims 1-6 is adopted. wherein, is the amount of oil in the tank, represents the attitude of the tank at the attitude quaternion is the height of the liquid surface corresponding to the liquid surface area of the liquid surface.

12. The unmanned aerial vehicle real-time fuel detection method of claim 11, wherein, Attitude quaternion of the tank is given by the strapdown attitude reference system of the airborne flight controller.

13. A drone, characterized in that, ​

Images