Flight device

Abstract

To provide a flight device that can measure a weight of a transported object accurately with a simple configuration.SOLUTION: A flight device 10 is provided with a rotor 11, a motor 12, a flight sensor 13, a power conversion unit 14, and a computational control unit 15. The flight sensor 13 measures a physical quantity acting on an airframe base 16. The computational control unit 15 generates an instruction signal on the basis of the physical quantity so that the airframe base 16 assumes a prescribed position and attitude. The power conversion unit 14 regulates an amount of electric power supplied to the motor 121 and the like on the basis of the inputted instruction signal. Additionally, the computational control unit 15 calculates an estimated weight, that is, an estimated value of a weight of a transported object, on the basis of a magnitude of the instruction signal.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a flying device. [Background technology]

[0002] 2. Description of the Related Art There have been known unmanned flying devices capable of flying in the air. Such flying devices are capable of flying in the air by using the thrust of a rotor that is driven to rotate around a vertical axis.

[0003] Possible fields of application of the flying device include, for example, the transportation field, the surveying field, the photography field, the agricultural field, etc. When the flying device is applied to such fields, various devices and medicines are attached to the flying device.

[0004] In order to ensure stable flight of the flying device, it is necessary to measure the weight of various devices and medicines that the flying device transports. Patent Documents 1 and 2 describe inventions that estimate the remaining amount in a tank equipped in the flying device.

[0005] In Patent Document 1, a load cell is used as a weight measuring device. By using the load cell, the weight difference with the weight of an empty tank can be measured, and the remaining amount in the attached tank during pesticide spraying can be detected. Therefore, it is possible to detect the remaining amount of pesticide without using a flow meter.

[0006] Patent Document 2 describes a remaining amount acquiring means for acquiring information on the remaining amount of the content in an aerosol container, in which the remaining amount information of the content in the aerosol container is detected by a weight sensor. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2020-117203 A [Patent Document 2] JP 2020-142772 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, the flying devices described in the above Patent Documents 1 and 2 have room for improvement in terms of measuring the weight of the transport object transported by the flying device at low cost.

[0009] Specifically, the inventions described in Patent Documents 1 and 2 are provided with a dedicated load cell or weight sensor to detect the remaining amount in the tank, which may lead to high costs. Also, the load acting on the load cell or weight sensor may not accurately reflect the remaining amount in the tank depending on the flight state of the flight device, so there is room for improvement in terms of accurately estimating the remaining amount in the tank.

[0010] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a flying device that can accurately measure the weight of a transportation object with a simple configuration. [Means for solving the problem]

[0011] The flying device of the present invention is a flying device that transports a transport body and is equipped with a rotor, a motor, a flight sensor, a power conversion unit, and a calculation control unit, wherein the rotor generates thrust for levitating the aircraft base unit by rotating, the motor drives the rotor to rotate, the flight sensor measures physical quantities acting on the aircraft base unit, the calculation control unit generates a DUTY value based on the physical quantities to place the aircraft base unit in a predetermined position and attitude, the power conversion unit adjusts the amount of power supplied to the motor based on the input DUTY value, and further, the calculation control unit calculates an estimated weight, which is an estimate of the weight of the transport body, based on the magnitude of the DUTY value while the altitude of the flying device is changing. Effect of the Invention

[0012] According to the flying device of the present invention, it is possible to provide a flying device that can accurately measure the weight of a transport object with a simple configuration. [Brief description of the drawings]

[0013] [Figure 1] 1A and 1B are diagrams showing a flying device according to an embodiment of the present invention, in which (A) is a top view showing the flying device, and (B) is a front view showing the flying device. [Diagram 2] 1 is a block diagram showing a connection configuration of a flying device according to an embodiment of the present invention. [Diagram 3] 1 is a flowchart illustrating a method for calculating an estimated weight value of a vehicle in a flying device according to an embodiment of the present invention. [Figure 4] 6 is a graph showing changes over time in motor output value and spray state in a flying device according to an embodiment of the present invention. [Diagram 5] 5 is a graph showing changes over time in motor output value and the movement speed of a flying device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The flying device 10 according to this embodiment will be described below with reference to the drawings. In the following description, the same components are generally given the same reference numerals, and repeated description will be omitted. In the following description, the terms up, down, front, back, left, and right are used, but the left and right refer to the left and right when the flying device 10 is viewed from the front in FIG. 1(A).

[0015] FIG. 1(A) is a top view showing the flight device 10, and FIG. 1(B) is a front view showing the flight device 10. As shown in FIG.

[0016] 1(A), the flying device 10 mainly comprises an aircraft base unit 16, a power unit (not shown here) mounted on the aircraft base unit 16, arms 271 etc. extending from the periphery of the aircraft base unit 16 toward the periphery, motors 121 etc. disposed on the outer ends of the arms 271 etc., and rotors 111 etc. rotated by the motors 121 etc. In the following description, the motors 121 etc. are collectively referred to as motors 12, and the rotors 111 etc. are collectively referred to as rotors 11.

[0017] The flying device 10 is capable of floating and moving in the air by rotating the rotor 111 at a predetermined rotational speed using the motor 121 etc., using power obtained from a battery stored in the aircraft base unit 16. Here, the flying device 10 is shown as an example for spraying pesticides on farm fields such as rice paddies.

[0018] The aircraft base 16 is disposed in the center of the flight device 10 and houses various devices (not shown). The outer skin of the aircraft base 16 is covered with a synthetic resin plate or a steel plate molded into a predetermined shape. A chemical tank 29 for storing a chemical 20 (described later) is built into the aircraft base 16.

[0019] Arms 271, 272, 273 and 274 extend outward from power conversion unit 14.

[0020] The motor 121 and the rotor 111 are disposed at the outer end of the arm 271. The motor 122 and the rotor 112 are disposed at the outer end of the arm 272. The motor 123 and the rotor 113 are disposed at the outer end of the arm 273. The motor 124 and the rotor 114 are disposed at the outer end of the arm 274. Here, the rotor 111 etc. rotate to generate thrust for levitating the machine base unit 16. Also, the motor 121 etc. rotationally drives the rotor 111 etc.

[0021] The chemical 20 stored in the chemical tank 29 may be liquid pesticide, granular pesticide, or the like.

[0022] 1(B), legs 32 and 33 that come into contact with the ground during landing are disposed on the lower part of the aircraft base part 16. The legs 32 and 33 are members also called skids, and when the flight device 10 is in a state of landing, the lower ends of the legs 32 and 33 come into contact with the ground.

[0023] A spraying device 18 for spraying a chemical 20 is disposed below the machine body base portion 16. The spraying device 18 has a built-in pump for transporting the chemical 20.

[0024] In addition, a support arm 19 extending upward on the right side is connected to the leg 32, and a nozzle 36 is attached to the upper end of the support arm 19. Similarly, a support arm 34 extending upward on the left side is connected to the leg 33, and a nozzle 35 is attached to the upper end of the support arm 34. The nozzles 35 and 36 are connected to the spraying device 18 via a pipe 37.

[0025] The spraying device 18 operates the pump of the spraying device 18 during the spraying on state based on instructions from the control device 28 described later. In this way, the chemical 20 stored in the chemical tank 29 is sprayed downward from the nozzles 35 and 36 via the pipe 37 by the pressure of the spraying device 18. On the other hand, during the spraying off state based on instructions from the control device 28 described later, the pump of the spraying device 18 is not operated, and the chemical 20 is not sprayed from the nozzles 35 and 36.

[0026] FIG. 2 is a block diagram showing the connection configuration of the flight device 10.

[0027] The flying device 10 mainly comprises a motor 121, a flight sensor 13, a power conversion unit 14, and an arithmetic and control unit 15, and transports a drug 20 as a transporter. The flying device 10 further comprises a communication unit 25, a battery 21, and the power conversion unit 14. The pilot 28 is operated on the ground by a pilot who pilots the flying device 10. The communication unit 26, the display device 22, and the display unit 23 are installed in the vicinity of the pilot.

[0028] The flight sensor 13 measures physical quantities acting on the aircraft base unit 16, and transmits a signal indicating the magnitude of this physical quantity to the calculation control unit 15. The sensors included in the flight sensor 13 are, for example, an acceleration sensor, an angular velocity sensor, a geomagnetic sensor, an air pressure sensor, and a GNSS antenna. The acceleration sensor detects changes in tilt and movement as physical quantities. The angular velocity sensor detects changes in tilt and orientation as physical quantities. The geomagnetic sensor detects direction as a physical quantity by magnetic force. The air pressure sensor detects altitude as a physical quantity. The GNSS antenna identifies position.

[0029] The calculation control unit 15 has a calculation device consisting of a CPU (Central Processing Unit) and a storage device consisting of a RAM (Random Access Memory) and a ROM (Read Only Memory), and controls the operation of the entire flight device 10. Furthermore, the calculation control unit 15 adjusts the amount of power supplied to the motor 121, etc., based on an instruction signal input from the flight sensor 13, as will be described later. Furthermore, the calculation control unit 15 calculates an estimated remaining amount, which is an estimated value of the remaining amount of the drug 20, which is a transporter, based on the magnitude of the instruction signal, as will be described later.

[0030] The arithmetic and control unit 15 has a flight controller 17 and a companion controller 24.

[0031] The flight controller 17 generates an instruction signal for setting the position, attitude, moving speed, etc. of the flying device 10 to a predetermined value based on the signal input from the flight sensor 13. For example, a DUTY value in PWM control can be used as this instruction signal. In this embodiment, since the flying device 10 has four motors 121, 122, 123, and 124, the DUTY value is calculated for each of the motors 121.

[0032] The companion controller 24 calculates an estimated remaining amount of the drug 20 based on information input from the flight controller 17, for example, information input from the flight sensor 13, information indicating the voltage of the battery 21, etc.

[0033] The power conversion unit 14 has ESC141 to ESC144. Here, ESC is an abbreviation of Electric Speed ​​Controller, and is an electronic device that controls the rotation speed of the motor 12. The ESC141 is disposed between the motor 121 and the calculation control unit 15, and controls the rotation speed of the motor 121. The ESC142 is disposed between the motor 122 and the calculation control unit 15, and controls the rotation speed of the motor 122. The ESC143 is disposed between the motor 123 and the calculation control unit 15, and controls the rotation speed of the motor 123. The ESC144 is disposed between the motor 124 and the calculation control unit 15, and controls the rotation speed of the motor 124. If the DUTY value input from the flight controller 17 is large, the ESC141 to ESC144 rotate the motor 121 to the motor 124 at a high speed.

[0034] Here, we will explain the basic flight operations of the flight device 10. The flight device 10 can perform each of the following operations: ascent, hovering, movement, and descent. The operations of the flight device 10 are executed by the flight controller 17 based on commands transmitted from the pilot 28 based on the operation of the operator.

[0035] In each of the above operations, the flight controller 17 adjusts the rotational speed of the motors 121 to 124 based on information input from the acceleration sensor and angular velocity sensor included in the flight sensor 13 so that the attitude of the flight device 10 is predetermined.

[0036] In the ascent operation, the flight controller 17 rotates the motor 12 at a relatively high speed so that the flight device 10 ascends to a predetermined altitude. Basically, the flight controller 17 outputs approximately the same DUTY value to the ESCs 141 to 144, and makes the rotation speeds of the motors 121 to 124 approximately the same. In addition, based on information input from the air pressure sensor included in the flight sensor 13, the flight controller 17 executes a hovering operation to keep the altitude of the flight device 10 approximately constant once the flight device 10 ascends to a predetermined altitude.

[0037] In the hovering operation, the flight controller 17 adjusts the rotation speed of the motors 121 to 122 so that the altitude of the flight device 10 is approximately constant, based on information input from a barometric pressure sensor included in the flight sensor 13. Basically, the flight controller 17 outputs approximately the same DUTY value to the ESCs 141 to 144, and keeps the rotation speeds of the motors 121 to 124 approximately the same.

[0038] In the movement operation, the flight controller 17 adjusts the rotation speed of the motors 121 to 124 so that the flight device 10 can move in each of the forward, backward, left and right directions at a predetermined speed. For example, the rotation speed of the motors 121 and 122 is made faster than the rotation speed of the motors 123 and 124. That is, the flight controller 17 makes the DUTY value output to the ESCs 141 and 142 greater than the DUTY value output to the ESCs 143 and 144. In this way, referring to FIG. 1(A), the rotors 111 and 112 rotate faster than the rotors 113 and 114, the airframe base unit 16 of the flight device 10 is in an inclined attitude, and the flight device 10 moves in a predetermined direction.

[0039] Thereafter, when it is recognized that the flight device 10 has reached a predetermined position based on the output of the GNSS antenna or the like included in the flight sensor 13, the flight controller 17 executes a braking operation. For example, the flight controller 17 makes the rotation speed of the motors 121 and 122 slower than the rotation speed of the motors 123 and 124. That is, the flight controller 17 makes the DUTY value output to the ESCs 143 and 144 greater than the DUTY value output to the ESCs 141 and 142. In this way, referring to FIG. 1(A), the rotors 111 and 112 rotate slower than the rotors 113 and 114, and the planar movement of the flight device 10 can be stopped. Then, the flight controller 17 executes a hovering operation.

[0040] In the descending operation, the flight controller 17 rotates the motor 12 at a relatively slow speed so that the flight device 10 descends to a predetermined altitude. Basically, the flight controller 17 outputs substantially the same DUTY value to the ESCs 141 to 144, and makes the rotation speeds of the motors 121 to 124 substantially the same. In addition, based on information input from the air pressure sensor included in the flight sensor 13, the flight controller 17 executes a hovering operation to keep the altitude of the flight device 10 substantially constant once the flight device 10 descends to a predetermined altitude.

[0041] FIG. 3 is a flow chart illustrating a method for calculating an estimated remaining amount of a drug 20, which is a transporter, in a flight device 10.

[0042] In step S10, the flight sensor 13 measures physical quantities. Specifically, an acceleration sensor, an angular velocity sensor, a geomagnetic sensor, an air pressure sensor, a GNSS antenna, and the like included in the flight sensor 13 measure the position, attitude, and the like of the flight device 10. The physical quantities measured by the flight sensor 13 are input to the flight controller 17. In addition, the operating conditions of the flight device 10 during flight are also input to the flight controller 17.

[0043] In step S11, the flight controller 17 calculates a DUTY value as an instruction signal based on the above-mentioned physical quantities. The flight controller 17 outputs the DUTY value based on the various information input in step S10, the operating conditions, etc. The flight controller 17 calculates the DUTY value for each of the ESCs 141 to 144 shown in FIG. 2.

[0044] Here, the DUTY value also changes depending on the weight of the flight device 10 including the pesticide 20. That is, when spraying pesticides, the altitude of the flight device 10 needs to be kept approximately the same in order to effectively spray the pesticide on plants such as rice. Also, at the beginning of pesticide spraying, the weight of the pesticide 20 is heavy, so the DUTY value selected by the flight controller 17 is relatively large. On the other hand, as the pesticide spraying progresses, the weight of the pesticide 20 becomes lighter, so the DUTY value selected by the flight controller 17 becomes relatively small.

[0045] Here, the flight controller 17 may average the DUTY values ​​calculated for each of the ESCs 141 to 144 in order to accurately estimate the weight of the drug 20 in a later step. The DUTY values ​​calculated for each of the ESCs 141 to 144 vary depending on the attitude and flight state of the flight device 10. Therefore, by calculating a DUTY average value (instruction signal average value) which is the average value of these four DUTY values, the influence of the attitude and flight state can be eliminated. Therefore, as described later, regardless of the flight state of the flight device 10, the estimated remaining amount of the drug 20 can be accurately calculated from the average value of the DUTY values. The calculated DUTY average value is input to the companion controller 24.

[0046] In step S12, the companion controller 24 calculates an estimated remaining amount of the drug 20, which is an estimated weight value. Specifically, the companion controller 24 reads a DUTY average value and a battery voltage value, which is a voltage value of the battery 21. Then, the companion controller 24 calculates an estimated remaining amount of the drug 20 based on a predetermined function having the DUTY average value and the battery voltage value as variables.

[0047] In this embodiment, the estimated remaining amount of the drug 20 is calculated taking into account the average duty value and the battery voltage value. The reason is that when the battery voltage value becomes low, the flight controller 17 increases the duty value in order to rotate the motor 12 at a predetermined rotation speed. Therefore, as the spraying of the drug 20 using the flight device 10 progresses, the duty value gradually increases, so if the estimated remaining amount of the drug 20 is calculated using only the duty value as a variable, the estimated remaining amount may be overestimated. Therefore, in this embodiment, the duty value is corrected by the battery voltage value to accurately calculate the estimated remaining amount of the drug 20.

[0048] In step S13, the companion controller 24 and the flight controller 17 transmit information indicating the estimated remaining amount of the drug 20. Specifically, the information indicating the estimated remaining amount of the drug 20 is transmitted from the flight device 10 to the display device 22 via the communication unit 25 and the pilot 28 by wireless communication.

[0049] In step S14, the estimated remaining amount of the drug 20 is displayed on the display unit 23 of the display device 22. The pilot can know the estimated remaining amount of the drug 20 by visually checking the display unit 23. Therefore, when the estimated remaining amount of the drug 20 becomes equal to or less than a certain amount, the pilot can move the flying device 10 to a predetermined location and replenish the drug 20.

[0050] 4 is a graph showing the change over time in the motor output value and the spraying state in the flight device 10. The horizontal axis of this graph shows the elapsed time, and the vertical axis shows the motor output (DUTY value) and the on / off state of the spraying switch. Here, when the spraying switch is in the on state, the spraying device 18 sprays the drug 20. On the other hand, when the spraying switch is in the off state, the spraying device 18 does not spray the drug 20.

[0051] Here, the DUTY values ​​output from the flight controller 17 to each of the ESCs 141 to 144 are shown in order to rotate the four motors 121 to 124 equipped in the flight device 10. The DUTY value output to the ESC 141 is shown by a solid line, the DUTY value output to the ESC 142 is shown by a dashed line, the DUTY value output to the ESC 143 is shown by a dashed line, and the DUTY value output to the ESC 144 is shown by a dashed line. The on / off state of the spray switch is also shown by a solid line.

[0052] In this graph, the DUTY value input to ESC141 to ESC144 gradually decreases over time while the spray switch is on. On the other hand, while the spray switch is off, the DUTY value input to ESC141 to ESC144 does not change. The reason why such an event is shown is that while the spray switch is on, the remaining amount of the drug 20 gradually decreases, and the DUTY value required to keep the altitude of the flight device 10 constant becomes smaller. Therefore, it can be understood that the amount of decrease in the DUTY value has a positive correlation with the amount of decrease in the drug 20, and the remaining amount of the drug 20 can be estimated from the DUTY value.

[0053] 5 is a graph showing the change over time in the motor output value and the movement speed of the flight device 10. The horizontal axis of this graph shows the elapsed time, and the vertical axis shows the pitch operation (forward and backward movement operation) and the average motor output (average DUTY value) of the flight device 10. The pitch operation is shown by a solid line, and the average motor output is shown by a dotted line.

[0054] Referring to this diagram, the pilot can operate the controller 28 to cause the flight device 10 to move forward, brake, and reverse. These operations are repeated when the flight device 10 sprays pesticides. When the flight device 10 executes forward, brake, and reverse movements, the DUTY values ​​input from the flight controller 17 to each of the ESCs 141 to 144 change significantly.

[0055] On the other hand, the average duty value shown by the dotted line shows some fluctuations, but no large fluctuations are observed in the forward, brake, and reverse operations. From this, by estimating the remaining amount of the drug 20 based on the average duty value, it is possible to stably and accurately estimate the remaining amount of the drug 20 regardless of the operating status of the flight device 10.

[0056] The above-described embodiment can provide the following main effects.

[0057] According to the flight device 10 of the present invention, the weight of the transport body can be estimated from the command signal generated to set the aircraft base unit 16 in a predetermined position and attitude. Therefore, the weight of the transport body can be estimated without the need for a dedicated weight sensor.

[0058] Furthermore, since the remaining amount of the pesticide 20 can always be calculated from the average duty, the remaining amount of the pesticide 20 being sprayed can be estimated in real time.

[0059] Furthermore, by calculating the estimated weight of the drug 20 based on the average DUTY value, the estimated weight of the drug 20 can be stably calculated whether in a hovering state or in a moving state.

[0060] Furthermore, when calculating the estimated weight of the drug 20, by taking into consideration the voltage value of the battery 21 in addition to the average DUTY value, the estimated weight can be calculated more accurately.

[0061] Although the embodiment of the present invention has been described above, the present invention is not limited to this, and modifications can be made without departing from the scope of the present invention. In addition, the above-described embodiments can be combined with each other.

[0062] FIG. 1 illustrates an example of an electric drone that uses only a battery as an energy source as the flight device 10, but a hybrid drone that uses both an engine and a battery as an energy source may also be used.

[0063] In the above-described embodiment, the estimated remaining amount of the drug 20 is calculated based on the average duty value, but the estimated remaining amount can also be calculated using a non-averaged duty value. For example, the estimated remaining amount can also be calculated using any one of the duty values, the median value of the duty values, or the like.

[0064] In the above-described embodiment, the estimated remaining amount of the drug 20 is calculated based on the average duty value and the battery voltage value, but the estimated remaining amount can also be calculated using only the average duty value.

[0065] In the above-described embodiment, the remaining amount of the drug 20 as a transporter is estimated from the DUTY value, but an object other than the drug 20 can also be used as the transporter.

[0066] The invention that can be understood from the above-described embodiment will be described below together with its effects.

[0067] The flying device of the present invention further includes a spraying device, the transport body is a drug to be sprayed by the spraying device, and the calculation control unit calculates an estimated remaining amount, which is an estimated value of the remaining amount of the drug, based on the magnitude of the instruction signal. Therefore, according to the flying device of the present invention, the remaining amount of the drug being sprayed can be estimated in real time.

[0068] In addition, the flying device of the present invention has a plurality of rotors, motors, and power conversion units, and the arithmetic control unit generates a plurality of the command signals to be input to each of the power conversion units, and further estimates the estimated weight of the transport body based on the command signal average value, which is the average value of the command signals. Therefore, according to the flying device of the present invention, by estimating the estimated weight of the transport body based on the command signal average value, the weight of the transport body can be stably estimated whether in a hovering state or a moving state.

[0069] The flight device of the present invention is further characterized in that it includes a battery that supplies power to the power conversion unit, and the calculation control unit calculates the estimated weight based on the instruction signal and the voltage value of the battery. Therefore, according to the flight device of the present invention, the estimated weight can be calculated more accurately by taking into account the voltage value of the battery in addition to the instruction signal when calculating the estimated weight.

[0070] In addition, in the flying device of the present invention, the signal indicating the estimated weight is transmitted to a display device, and the estimated weight is displayed on the display unit of the display device. Therefore, according to the flying device of the present invention, for example, an operator of the flying device can know the estimated weight of the transport body in real time. [Explanation of symbols]

[0071] 10 Flight equipment 11 Rotor 111 Rotor 112 Rotor 113 Rotor 114 Rotor 12 Motor 121 Motor 122 Motor 123 Motor 124 Motor 13 Flight Sensors 14 Power conversion section 141 ESC 142 ESC 143 ESC 144 ESC 15 Calculation control unit 16 Aircraft base 17 Flight Controller 18 Spraying equipment 19 Support arm 20 Drugs 21 Battery 22 Display device 23 Display section 24 Companion Controller 25 Communications Department 26 Communications Department 271 Arm 272 Arm 273 Arm 274 Arm 28 Pilot 29 Chemical Tank 32 Legs 33 Legs 34 Support arm 35 Nozzle 36 Nozzles 37 Pipe

Claims

[Claim 1] A flying device that transports a vehicle, the flying device comprising a rotor, a motor, a flight sensor, a power conversion unit, and a calculation control unit, The rotor generates thrust for levitating the aircraft base unit by rotating; The motor drives the rotor to rotate, The flight sensor measures a physical quantity acting on the aircraft base section, the calculation control unit generates a DUTY value based on the physical quantity so as to place the aircraft base unit in a predetermined position and attitude; The power conversion unit adjusts the amount of power supplied to the motor based on the input DUTY value, Furthermore, the calculation control unit calculates an estimated weight, which is an estimate of the weight of the transport body, based on the magnitude of the DUTY value while the altitude of the flight device is changing.

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