Aircraft and control method of aircraft

Abstract

The aircraft includes: a sensor device that detects a flight state of the aircraft; the ejection device comprises a parachute and can eject the parachute; and a controller that determines whether or not there is a need to eject the parachute on the basis of the degree of separation of the flight state from the reference range determined for the flight state and the duration during which the separation state that is equal to or greater than the degree of separation continues.

Description

Technical Field

[0001] The present disclosure relates to an aircraft and a control method of an aircraft. Background Art

[0002] Conventionally, various manned aircraft and various unmanned aircraft are known as aircraft. In addition, unmanned aircraft that perform a parachute landing scenario when departing from a reference range (also referred to as a "flight envelope") determined for a flight state are also known.

[0003] For example, U.S. Patent Application Publication No. 2017 / 0106986A1 (Patent Document 1) discloses an unmanned aerial vehicle that performs such a descent scenario. In the unmanned aerial vehicle of Patent Document 1, for example, a parachute is ejected when the inclination of the unmanned aerial vehicle is greater than a threshold value (25 degrees) and the duration of such an inclination state is longer than a threshold value (2 seconds) and the altitude is higher than a threshold value (20 feet). Prior Art Literature Patent Literature

[0004] Patent document 1: U.S. Patent Application Publication No. 2017 / 0106986A1. Summary of the invention Problems to be solved by the invention

[0005] In Patent Document 1, even if a flight slightly below the threshold value of the inclination (for example, a flight with an inclination of 24 degrees) continues for a sufficiently longer time (for example, 5 seconds) than the threshold value of the period, the descent scene will not start. In addition, even if a flight that greatly exceeds the threshold value of the inclination continues for a shorter time (for example, 1.5 seconds) than the threshold value of the period, the descent scene will not start. Therefore, in Patent Document 1, there is a risk that the unmanned aerial vehicle will fall during this period. Thus, in Patent Document 1, it cannot be said that the descent scene including the ejection of the parachute is not necessarily executed at the appropriate time.

[0006] The present disclosure has been made in view of the above-mentioned problems, and provides an aircraft and an aircraft control method capable of ejecting a parachute at an appropriate timing. Solutions to Solve Problems

[0007] According to one aspect of the present disclosure, an aircraft comprises: a sensor device that detects a flight state of the aircraft; an ejection device that includes a parachute and is capable of ejecting the parachute; and a controller that determines whether it is necessary to eject the parachute based on a degree of departure of the flight state from a reference range determined for the flight state and a duration of the departure state above the degree of departure.

[0008] According to another aspect of the present disclosure, a control method for an aircraft capable of ejecting a parachute comprises: a step of detecting the flight state of the aircraft; and the following step: judging whether it is necessary to eject the parachute based on the degree of departure of the flight state from a reference range determined for the flight state and the duration of the departure state above the departure degree. Effects of the Invention

[0009] According to the present disclosure, the parachute can be ejected at an appropriate timing. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a diagram showing the flying status of a drone. Figure 2 This is a diagram showing a state where the drone is lowered with the parachute ejected. Figure 3 This is a block diagram used to illustrate the hardware structure of a drone. Figure 4 It is a diagram showing a configuration example of a trigger device. Figure 5 This is the main view of the remote controller used by the operator to control the drone. Figure 6 This is a diagram for explaining the setting of the threshold value of the combined acceleration. Figure 7 This is a diagram for explaining the setting of the threshold value of the angular velocity. Figure 8 This is a diagram for explaining the setting of the threshold value of the attitude angle. Fig. 9 is a graph showing a function. Fig.10 is a graph showing a function. Fig.11 It is a flowchart for explaining the flow of processing. Fig.12 is a graph showing a function. Fig.13 is a graph showing a function. Fig.14 It is a diagram showing a data table. Fig.15 It is a flowchart for explaining the flow of processing. DETAILED DESCRIPTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in the following description, the same parts and components are marked with the same reference numerals. Their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0012] Hereinafter, as an example of an aircraft, an unmanned aircraft will be described as an example. Specifically, as the unmanned aircraft, a drone will be described as an example. More specifically, a drone with a rotary wing will be described as an example. In addition, the present disclosure can also be applied to various manned aircraft (another example of an aircraft) such as an "aerial vehicle".

[0013] [Embodiment 1] <A. Outline of the Drone> The drone according to the present embodiment can perform automatic control and manual control (remote operation using a remote controller) by an operator. Figure 1 It is a diagram showing the state of the drone in flight. Figure 2 It is a diagram showing the state in which the drone is descending with a parachute ejected.

[0014] As shown in Figure 1 and Figure 2 , the drone 1 includes a main body 2, four arms 3A, 3B, 3C, 3D, four propulsion mechanisms 4A, 4B, 4C, 4D, an ejection device 5, a communication unit 6, and a support member 18. Each of the propulsion mechanisms 4A, 4B, 4C, 4D includes a propeller 41 (refer to Figure 2 ).

[0015] In addition, hereinafter, for the sake of convenience of explanation, any one of the arms 3A, 3B, 3C, 3D will also be referred to as "arm 3". Similarly, any one of the propulsion mechanisms 4A, 4B, 4C, 4D will also be referred to as "propulsion mechanism 4".

[0016] The arm 3 is attached to the main body 2. The arm 3 has a base end portion and a distal end portion. The base end portion of the arm 3 is attached to the main body 2. In this example, the arm 3 extends from the side surface of the main body 2.

[0017] At the distal end portion of the arm 3, the propulsion mechanism 4 is attached. At the distal end portion of the arm 3, the motor 42 is attached. The propeller 41 is attached to the rotation shaft (not shown) of the motor 42.

[0018] In this example, the ejection device 5 is attached to the upper surface (top surface) of the main body 2. In addition, the attachment position of the ejection device 5 is not limited thereto, and for example, it may be the side surface or the bottom surface of the main body 2.

[0019] The ejection device 5 houses the parachute 51. If the flight state of the drone 1 satisfies a predetermined condition, then as shown in Figure 2As shown, the ejection device 5 ejects the parachute 51. The ejection device 5 detects the fall of the drone 1, etc., and instantaneously deploys the parachute 51 by operating a gas generator built into the ejection device 5. In addition, as the gas generator, either a gunpowder-type gas generator (pyrotechnics) or a non-gunpowder-type gas generator such as a gas cylinder type can be used.

[0020] In this example, the support member 18 extends upward from the connection part of the arm 3 and the main body 2. The support member 18 is a hollow tube. The wiring for the communication unit 6 passes through the inside of the support member 18. In this example, the communication unit 6 is supported by the support member 18 so as to be located above the main body 2.

[0021] In addition, as an example of the drone 1, an example having 4 arms 3 and 4 propulsion mechanisms 4 is cited, but the number of arms and the number of propulsion mechanisms are not limited to this.

[0022] <B. Hardware Configuration and Processes Performed> Figure 3 is a block diagram for explaining the hardware configuration of the drone 1. In addition, in Figure 3 the main power path is represented by a solid line and the main signal path is represented by a dotted line.

[0023] As Figure 3 shown, in addition to the above-mentioned propulsion mechanisms 4A, 4B, 4C, 4D, ejection device 5, and communication unit 6, the drone 1 further includes drive devices (ESC: Electronic Speed Controller) 7A, 7B, 7C, 7D, a flight controller (Autopilot), a battery 9, a power module 10, a distributor 12, a battery 13, a trigger device (ATS: Auto Trigger System) 14, a sensor 15, and a GNSS (Global Navigation Satellite System) receiver 16. In addition, hereinafter, for the sake of convenience of explanation, any one of the drive devices 7A, 7B, 7C, 7D is also referred to as the "drive device 7".

[0024] As described above, the propulsion mechanism 4 includes a propeller 41 and a motor 42. The drive device 7 includes an MCU (Micro Controller Unit) and a current driver (not shown).

[0025] The flight controller 8 includes an MCU 81, an inertial device 82, and a barometric altimeter 83. The MCU 81 is communicably connected to the inertial device 82 and the barometric altimeter 83.

[0026] The trigger device 14 includes an MCU 141, an inertial device 142, and a barometric altimeter 143. In this example, the inertial device 142 detects the acceleration, angular velocity, attitude angle, and velocity of the drone 1. The details of the inertial device 142 are described later. The barometric altimeter 143 periodically measures the altitude of the drone 1 (the altitude from the ground level and the sea level).

[0027] Specifically, the MCU 81, 141 has a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and other memories, and an I / O (Input / Output) circuit (not shown). Programs and data are stored in the memory. For example, data showing the flight path of the drone 1 is stored in the memory of the MUC 81.

[0028] The communication unit 6 is a device for communicating with a ground device and includes a wireless module and an LTE (Long Term Evolution) module (not shown).

[0029] The wireless module is a communication module for communicating with the remote controller 900, which is one of the ground devices. When the drone 1 is manually operated within the range visible to the operator, the communication between the wireless module and the remote controller 900 is utilized. Therefore, the communication has real-time characteristics.

[0030] The LTE module is a communication module for communicating with a ground control station via a base station (not shown). When the drone 1 is automatically operated to fly even for several kilometers, the communication between the LTE module and the ground control station, which is one of the ground devices, is utilized.

[0031] The battery 9 is a storage battery (secondary battery). The battery 9 is connected to a power module 10. The power module 10 supplies power from the battery 9 to the flight controller 8 and the communication unit 6 using a predetermined power path. In this example, the communication unit 6 is powered via the flight controller 8. The power module 10 supplies power from the battery 9 to the distributor 12 using a predetermined power path.

[0032] The distributor 12 distributes the supplied power to each of the four drive devices 7. The distributor 12 supplies the power supplied through the power path R2 to each of the four drive devices 7. Specifically, the distributor 12 supplies the power to each of the current drivers (not shown) of the four drive devices 7.

[0033] The drive device 7 is connected to the flight controller 8 in a communicable manner. The drive device 7 drives the corresponding propulsion mechanism 4 based on the instruction from the flight controller 8. In detail, the drive device 7 adjusts the propulsion force of the corresponding propulsion mechanism 4 based on the instruction from the flight controller 8. Specifically, the drive device 7A adjusts the propulsion force of the corresponding propulsion mechanism 4A. Similarly, the drive devices 7B, 7C, and 7D adjust the propulsion forces of the propulsion mechanisms 4B, 4C, and 4D, respectively. In this way, the drive device 7 functions as a control device for the propulsion mechanism 4.

[0034] Specifically, the MUC (not shown) of the drive device 7 receives a command from the MUC 81 of the flight controller 8. Based on the command, the MCU of the drive device 7 controls the current driver of the drive device 7 to flow the current to the coil (not shown) of the motor 42. By controlling the current flowing through the coil in this way, the rotation speed of the motor 42 is controlled. In this way, the rotation speed of the propeller 41 can be controlled.

[0035] The GNSS receiver 16 and the communication unit 6 are connected to the MCU 81 of the flight controller 8 in a communicable manner. The GNSS receiver 16 and the communication unit 6 are supplied with power from the flight controller 8. The GNSS receiver 16 and the communication unit 6 operate using power from the battery 9.

[0036] The GNSS receiver 16 receives radio waves transmitted from a plurality of positioning satellites (not shown), and acquires the current position of the drone 1 based on the received radio waves. The GNSS receiver 16 periodically transmits information indicating the current position to the flight controller 8. Specifically, the GNSS receiver 16 periodically transmits information on the latitude and longitude of the drone 1 as position information to the MCU 81.

[0037] The inertial device 82 periodically measures the angular velocity and acceleration of the drone 1 in three-dimensional space. In addition, as the inertial device 82, for example, any one of an inertial measurement unit (IMU), an inertial navigation unit (INU), an inertial reference unit (IRU), an inertial guidance unit (IGU), and an attitude heading reference system (AHRS). The barometric altimeter 83 periodically measures the height from the ground level and the sea level in the same manner as the barometric altimeter 143.

[0038] The flight controller 8 controls the flight of the drone 1. The flight controller 8 implements automatic control and manual control based on the operator's remote control operation.

[0039] In the case of automatic control, the flight controller 8 controls the flight of the drone 1 based on a predetermined flight route. Specifically, the MCU 81 of the flight controller 8 realizes the autonomous flight of the drone 1 based on the current position obtained by the GNSS receiver 16, etc., the detection result detected by the inertial device 82, and the detection result (altitude) detected by the barometric altimeter 83. The flight controller 8 can use the above-mentioned LTE module to send information on the current position of the drone 1.

[0040] When a predetermined abnormality occurs in the drone 1 , the flight controller 8 uses the LTE module to transmit information on the current position of the drone 1 to the ground control station.

[0041] The ejection device 5 includes a parachute 51. The ejection device 5 can eject the parachute 51 regardless of whether it is automatically operated or manually operated.

[0042] The trigger device 14 is powered by the battery 13. If the flight state satisfies a predetermined condition, the trigger device 14 activates the ejection device 5. Specifically, the MCU 141 transmits the above-mentioned command to the ejection device 5, and the ejection device 5 ejects the parachute 51 to the outside.

[0043] In more detail, if the flight state satisfies a predetermined condition, the trigger device 14 transmits a predetermined signal to the flight controller 8. If the flight controller 8 receives the predetermined signal, the rotation of the propeller 41 is stopped. That is, the flight controller 8 forcibly stops the flight. After a predetermined time has passed after the predetermined signal is transmitted, the trigger device 14 transmits a command to eject the parachute 51 to the ejection device 5. In this way, the parachute 51 is ejected after the propeller 41 stops. In this way, the parachute 51 can be prevented from being entangled with the propeller 41.

[0044] The sensor 15 detects whether the ejection device 5 is in operation. The sensor 15 is communicatively connected to the flight controller 8. The flight controller 8 transmits the forced stop of the flight and the result detected by the sensor 15 to the ground control station using the LTE module.

[0045] In addition, when the MCU 81 determines that the drone 1 has deviated from the flight path, it may transmit a command for operating the ejection device 5 to the trigger device 14. In this case, the MCU 141 of the trigger device 14 operates the ejection device 5 based on the command.

[0046] Figure 41 is a diagram showing an example of the configuration of the trigger device 14. Figure 4 As shown, the inertial device 142 includes a gyroscope 1421, an accelerometer 1422, and a processor 1423. In detail, the inertial device 142 includes three gyroscopes and three accelerometers for each axis (X axis, Y axis, Z axis) of the three-dimensional orthogonal coordinate system. In addition, the processor 1423 can also be in the MCU 141. The processor 1423 only needs to be in the trigger device 14.

[0047] Specifically, as the inertial device 142, similar to the inertial device 82, for example, any one of an inertial measurement unit (IMU), an inertial navigation unit (INU), an inertial reference unit (IRU), an inertial guidance unit (IGU), and an attitude and azimuth reference system (AHRS) can be used.

[0048] In this example, the forward direction of the drone 1 is the positive direction of the X-axis, and the backward direction of the drone 1 is the negative direction of the X-axis. The leftward moving direction of the drone 1 is the positive direction of the Y-axis, and the rightward moving direction of the drone 1 is the negative direction of the Y-axis.

[0049] The rotational motion of the drone 1 is detected by the gyroscope 1421. The translational motion of the drone 1 in each axial direction is detected by the accelerometer 1422. Specifically, in this example, the gyroscope 1421 outputs the angular velocity around the three axes to the processor 1423. The accelerometer 1422 outputs the acceleration in the three axial directions to the processor 1423.

[0050] The processor 1423 calculates at least the angular velocity around the three axes, the acceleration in the three axial directions, the attitude angle (roll angle, pitch angle, yaw angle (azimuth)), speed, and position. In addition, hereinafter, the angular velocity around the X axis among the angular velocities around the three axes is also referred to as the "roll angular velocity". The angular velocity around the Y axis among the angular velocities around the three axes is also referred to as the "pitch angular velocity". The angular velocity around the Z axis among the angular velocities around the three axes is also referred to as the "yaw angular velocity".

[0051] The MCU 141 has a memory 1411 and a determination unit 1412. The memory 1411 stores a function Va(x) and a function Vb(t). The details of the function Va(x) and the function Vb(t) are described later. The determination unit 1412 of the MCU 141 determines whether the ejection operation of the parachute 51 is required based on the function Va(x) and the function Vb(t) stored in the memory 1411. The details of such determination processing are also described later.

[0052] In addition, in the above, a set of two functions, namely the function Va(x) and the function Vb(t), is shown. More specifically, in the memory 1411, a number of function groups corresponding to the types of flight envelopes described later are stored.

[0053] <C. Remote Controller> Figure 5 is a front view of the remote controller 900 for an operator to control the unmanned aerial vehicle 1. As Figure 5 shown, the remote controller 900 is provided with joysticks 910 and 920. In addition, there are two types of operation methods for the unmanned aerial vehicle 1, namely "Mode 1" and "Mode 2". Hereinafter, the case of "Mode 1" will be described.

[0054] When the operator pushes the joystick 910 in the direction of arrow 951, the unmanned aerial vehicle 1 ascends. When the operator pushes the joystick 910 in the direction of arrow 952, the unmanned aerial vehicle 1 moves to the right as observed by the operator. When the operator pushes the joystick 910 in the direction of arrow 953, the unmanned aerial vehicle 1 descends. When the operator pushes the joystick 910 in the direction of arrow 954, the unmanned aerial vehicle 1 moves to the left as observed by the operator.

[0055] When the operator pushes the joystick 920 in the direction of arrow 961, the unmanned aerial vehicle 1 moves forward. When the operator pushes the joystick 920 in the direction of arrow 962, the unmanned aerial vehicle 1 makes a right turn. When the operator pushes the joystick 920 in the direction of arrow 963, the unmanned aerial vehicle 1 moves backward. When the operator pushes the joystick 920 in the direction of arrow 964, the unmanned aerial vehicle 1 makes a left turn.

[0056] <D. Setting of Flight Envelope> Next, a method for setting the flight envelope will be described. That is, a method for setting a reference range (range shown by a threshold) determined for the flight state will be described. Hereinafter, the setting of the threshold of the combined acceleration in three axial directions, the setting of the threshold of the angular velocity, and the setting of the threshold of the attitude angle will be exemplified and described. In addition, if the accelerations of the three axes are X, Y, and Z respectively, the combined acceleration is calculated using the following formula (1).

[0057] [Equation 1]

[0058] Figure 6951 and 953. The operator operates the operating lever 910 of the remote controller 900 to repeatedly move the drone 1 in the vertical direction (up and down direction). Specifically, the operator alternately repeats the operation of pushing the operating lever 910 in the direction of arrow 951 and the operation of pushing it in the direction of arrow 953. In this example, the operator operates the operating lever 910 with a predetermined ratio (e.g., about 70%) of the maximum operation amount in the directions of arrows 951 and 953.

[0059] In this case, the inertial device 142 is used to obtain Figure 6 The waveform W1 of the synthetic acceleration is shown. The horizontal axis of the waveform W1 is time, and the vertical axis is synthetic acceleration. The waveform W1 is a composite acceleration of 9.8 m / s 2 When only the vertical direction (Z-axis direction) is considered, the resultant acceleration is 9.8 m / s 2 The state indicates that the vertical upward acceleration and the vertical downward acceleration (gravity) are balanced. The resultant acceleration is 9.8 m / s 2 The state of indicates a state in which the force causing the drone 1 to rise and the force causing the drone 1 to fall are balanced.

[0060] The vertical axis value of the waveform W1 is “5.75 m / s 2 " indicates the lower limit value (minimum value) of the combined acceleration. Specifically, "5.75 m / s 2 " shows the lower limit of the resultant acceleration measured by the inertial device 142 in normal operation. When the resultant acceleration is 5.75 m / s 2 In the state, UAV 1 acts as a 9.8m / s 2 The difference is 4.05m / s 2 lower.

[0061] The lower limit of waveform W1 is the lower limit of the flight envelope of the synthetic acceleration. That is, this lower limit becomes the threshold for distinguishing between the flight state that satisfies the flight envelope and the flight state that does not satisfy the flight envelope. If the synthetic acceleration is lower than 5.75 m / s 2 , then it deviates from the flight envelope regarding the resultant acceleration.

[0062] Figure 7 3 is a diagram for explaining the setting of a threshold value of an angular velocity (in this example, a rolling angular velocity). Figure 8 : is a diagram for explaining the setting of the threshold value of the attitude angle (in this example, the roll angle).

[0063] The operator operates the operating lever 910 of the remote controller 900 to repeatedly move the drone 1 in the left and right directions. Specifically, the operator alternately repeats the operation of pushing the operating lever 910 in the direction of arrow 952 and the operation of pushing it in the direction of arrow 954. In this example, the operator operates the operating lever 910 in a predetermined ratio (about 70%) of the maximum operation amount in the directions of arrows 952 and 954.

[0064] In this case, the inertial device 142 is used to obtain Figure 7 The waveform W2 related to the angular velocity shown in FIG. Figure 8 The waveform W3 related to the attitude angle is shown.

[0065] like Figure 7 As shown, "60 deg / s" as the value of the vertical axis of the waveform W2 shows the upper limit value (maximum value) of the angular velocity. In detail, the upper limit value of the angular velocity measured by the inertial device 142 in normal operation is shown. The upper limit value of the waveform W2 is the upper limit value of the flight envelope of the angular velocity (in this example, the angular velocity around the X-axis). That is, the upper limit value becomes a threshold value for distinguishing between a flight state that satisfies the flight envelope and a flight state that does not satisfy the flight envelope. If the angular velocity exceeds 60 deg / s, it is out of the flight envelope regarding the angular velocity.

[0066] Similarly, "-60 deg / s" as the value of the vertical axis of the waveform W2 shows the lower limit value (minimum value) of the angular velocity. In detail, the lower limit value of the angular velocity measured by the inertial device 142 in normal operation is shown. The lower limit value of the waveform W2 is the lower limit value of the flight envelope of the angular velocity (in this example, the rolling angular velocity). That is, the lower limit value becomes a threshold value for distinguishing between a flight state that satisfies the flight envelope and a flight state that does not satisfy the flight envelope. If the angular velocity is lower than -60 deg / s, it is out of the flight envelope regarding the angular velocity.

[0067] In this way, the range of the flight envelope of the roll angular velocity is within the range of -60 degrees / second to 60 degrees / second. In addition, the range of the flight envelope of the pitch angular velocity is also set in the same way. Not limited to this, the range of the flight envelope of the pitch angular velocity may be made the same as the range of the flight envelope of the roll angular velocity in consideration of the shape of the drone 1.

[0068] like Figure 8As shown, "20.4deg", which is the value of the vertical axis of waveform W3, indicates the upper limit value (maximum value) of the attitude angle. Specifically, "20.4deg" indicates the upper limit value of the attitude angle measured by the inertial device 142 during normal operation. The upper limit value of the flight envelope with the upper limit value of waveform W3 as the angular velocity (in this example, the roll angle). That is, this upper limit value becomes a threshold for distinguishing between a flight state that satisfies the flight envelope and a flight state that does not satisfy the flight envelope. If the attitude angle exceeds 20.4deg, the flight envelope regarding the attitude angle is exceeded.

[0069] Similarly, "-15.0deg", which is the value of the vertical axis of waveform W3, indicates the lower limit value (minimum value) of the attitude angle. Specifically, "-15.0deg" indicates the lower limit value of the attitude angle (in this example, the roll angle) measured by the inertial device 142 during normal operation. However, based on the symmetry of the shape of the UAV 1, in this example, the lower limit value of the attitude angle is the value obtained by multiplying the upper limit value of the attitude angle by "-1" (i.e., "-20.4deg"). This lower limit value becomes a threshold for distinguishing between a flight state that satisfies the flight envelope and a flight state that does not satisfy the flight envelope. If the attitude angle is lower than -20.4deg, the flight envelope regarding the attitude angle is exceeded.

[0070] In this way, the range of the flight envelope of the attitude angle (in this example, the roll angle) becomes a range of -20.4deg or more and 20.4deg or less. In addition, by the same method, the range of the flight envelope of the pitch angle is also set. Not limited to this, considering the shape of the UAV 1, the range of the flight envelope of the pitch angle can be made the same as the range of the flight envelope of the roll angle.

[0071] Furthermore, through the operation of the UAV 1 as described above and the analysis of the waveform obtained by using this operation, the range of the flight envelope regarding the height change per unit time of the UAV 1 is set. Specifically, the MCU 141 sets the range of the flight envelope regarding the height change based on the detection result (height) detected by the barometric altimeter 143. In addition, the MCU 141 can also be configured to set the range of the flight envelope regarding the height change based on the detection result detected by the accelerometer 1422.

[0072] Hereinafter, for the sake of convenience of explanation, among the above-mentioned multiple flight envelopes, the flight envelope of the combined acceleration described based on Figure 6 is described.

[0073] <E. Determination Process Using a Function> In this example, the functions Va(x) and Vb(t) stored in the memory 1411 are functions related to the synthetic acceleration. Hereinafter, the functions Va(x) and Vb(t) will be described, and thereafter, the control using the functions Va(x) and Vb(t) will be described.

[0074] Fig. 9 is a graph showing the function Va(x). Fig. 9 As shown in FIG. 1 , the function Va(x) is a function that takes the flight state (specifically, the synthetic acceleration) of the drone 1 as an independent variable (i.e., x), and the value of the dependent variable (i.e., y) is proportional to the degree of departure of the flight state from the reference range (flight envelope) determined for the flight state. The value range of the dependent variable of the function Va(x) is greater than or equal to 0 and less than 1. That is, the value of the dependent variable of the function Va(x) will not be greater than 1.

[0075] Specifically, the function Va(x) is a membership function. The membership function extends the concept of characteristic function to fuzzy sets. In the function Va(x), in the range of x, 3.75 m / s 2 Above and 5.75m / s 2 In the range below, the value of y is proportional to the degree of departure from the flight envelope. 2 ” is from 5.75m / s 2 Subtract 9.8m / s 2 and 5.75m / s 2 The value after half the difference (about 2.0).

[0076] Value "5.75m / s 2 "It is Figure 6 In the function Va(x), let the combined acceleration be 5.75 m / s 2 The value of the function is 0.1. The resultant acceleration is 3.75 m / s 2 The value of the function is 0.9.

[0077] Specifically, the function Va(x) is represented by the following equations (2) and (3). Va(x)=-0.4x+2.4(3.75≦x≦5.75)……(2) Va(x)=0(x<3.75,5.75 <x)……(3) In the x range of 3.75m / s 2 Above and 5.75m / s 2In the following range, the value of y increases to the degree of detachment (the difference between x and 5.75) from the flight state of detachment from the flight envelope. For example, when x = P2 (where 3.75 ≤ P2 < P1), the value of y is greater than when x = P1 (where P1 ≤ 5.75).

[0078] Fig.10 is a graph showing the function Vb(t). As Fig.10 shown, the function Vb(t) is a function with the duration of detachment from the flight envelope as the independent variable (x), and the value of the dependent variable (y) is proportional to the duration. The range of the value of the dependent variable of the function Vb(t) is 0 or more and less than 1. That is, the value of the dependent variable of the function Vb(t) does not become 1 or more.

[0079] Specifically, the function Vb(t) is a membership function. In the range where x is 0.1 s or more and 0.5 s or less, the value of y is proportional to the degree of detachment from the flight state of detachment from the flight envelope. In the function Vb(t), the value of the function when the duration is 0.1 s is 0.1. The value of the function when the duration is 0.5 s is 0.9.

[0080] Specifically, the function Vb(t) is represented by the following equations (4) and (5). Vb(t) = 2t - 0.1 (0.1 ≤ t ≤ 0.5)……(4) Vb(t) = 0 (t < 0.1, 0.5 < t)……(5) In the range where t is 0.1 s or more and 0.5 s or less, the value of y increases proportionally to the value of the duration.

[0081] Next, the control using the functions Va(x) and Vb(t) will be described. Fig.11 is a flowchart for explaining the process executed in a certain situation. In addition, Fig.11 each of the steps S1 to S7 in is repeatedly executed in each predetermined control cycle (for example, every 0.01 seconds).

[0082] In step S1, the MCU 141 of the trigger device 14 acquires the combined acceleration P from the inertial device 142. In step S2, the MCU 141 substitutes the combined acceleration P as the value of x into the function Va(x) and obtains the value of the function (Va(P)).

[0083] For example, when the MCU 141 obtains the resultant acceleration P1 in step S1, the function value (Va(P1)) is obtained in step S2. In addition, Va(P1) is a value greater than 0.1 and less than 0.9. In the case where the MCU 141 obtains the resultant acceleration P2 in step S1, the function value (Va(P2)) is obtained in step S2. In addition, Va(P1) is a value greater than 0.1 and less than 0.9.

[0084] In step S3, the MCU 141 obtains the duration Tp of the state below the synthetic acceleration P. For example, when a plurality of different synthetic accelerations (e.g., synthetic acceleration P1 and synthetic acceleration P2) are obtained in step S1 of different control cycles, the MCU 141 obtains the duration Tp1 of the state below the synthetic acceleration P1 and the duration Tp2 of the state below the synthetic acceleration P2, respectively. In this way, the MCU 141 has a plurality of timer functions.

[0085] For example, when the combined acceleration state is during T1 and the combined acceleration decreases from P1 to P2, and the combined acceleration state is during T2, the duration Tp1 is at least the sum (cumulative value) of the periods T1 and T2.

[0086] In step S4, MCU 141 substitutes duration Tp as the value of t into function Vb(t) to obtain the value of the function (Vb(Tp)). As described above, when synthetic acceleration P1 and synthetic acceleration P2 are obtained in step S1 of different control cycles, MCU 141 obtains the value of the function when duration Tp1 is substituted into function Vb(t) (Vb(Tp1)) and the value of the function when duration Tp2 is substituted into function Vb(t) (Vb(Tp2)).

[0087] In step S5, the MCU 141 calculates the sum of the function Va(P) and the function Vb(Tp). In the above example, the MCU 141 calculates the sum of the function Va(P1) and the function Vb(Tp1) and the sum of the function Va(P2) and the function Vb(Tp2).

[0088] In step S6, the MCU 141 determines whether the sum of the function Va(P) and the function Vb(Tp) exceeds the threshold value of 1. In the above example, the MCU 141 determines whether the sum of the function Va(P1) and the function Vb(Tp1) exceeds 1 and whether the sum of the function Va(P2) and the function Vb(Tp2) exceeds 1.

[0089] When the sum of the function Va(P) and the function Vb(Tp) exceeds 1 which is the threshold value (Yes in step S6), the MCU 141 causes the ejection device 5 to eject the parachute 51. When the sum of the function Va(P) and the function Vb(Tp) does not exceed 1 which is the threshold value (No in step S6), the MCU 141 proceeds to the next control cycle and executes step S1 again.

[0090] <F. Summary> If the drone 1 is summarized, it is as follows.

[0091] 〔1〕The drone 1 includes: an inertial device 142 that detects the flight state of the drone 1; an ejection device 5 that includes a parachute 51 and is capable of ejecting the parachute 51; and an MCU (controller) 141 that determines whether it is necessary to eject the parachute 51 based on the degree of deviation of the flight state from a reference range (i.e., flight envelope) determined for the flight state and the duration of the deviation state above the degree of deviation.

[0092] According to such a configuration, the drone 1 determines whether it is necessary to eject the parachute 51 considering both the degree of deviation and the duration of the deviation state above the degree of deviation. Therefore, according to the drone 1, the parachute can be ejected at an appropriate timing.

[0093] 〔2〕The MCU 141 stores the function Va(x) and the function Vb(t). The function Va(x) is a function with the flight state as the independent variable, and the value of the dependent variable is proportional to the degree of deviation of the flight state from the flight envelope. The function Vb(t) is a function with the duration of the deviation as the independent variable, and the value of the dependent variable is proportional to the duration.

[0094] If the MCU 141 determines that the sum of the values of the dependent variables of the function Va(x) and the function Vb(t) during the flight of the drone 1 exceeds a predetermined threshold value (in this example, 1), it causes the ejection device 5 to eject the parachute 51.

[0095] According to such a configuration, it is possible to determine whether it is necessary to eject the parachute 51 based on the degree of deviation from the flight envelope and the duration of the deviation state above the degree of deviation, and eject the parachute 51 based on the determination result. Thus, specifically, the following control can be performed.

[0096] · The degree of deviation from the flight envelope is small, but since the duration of such a degree of deviation is long, the parachute 51 is ejected.

[0097] The degree of separation from the flight envelope is not that great, but the duration of such separation is long enough to a certain extent, so the parachute 51 is ejected.

[0098] Although the duration of the separation is short, the degree of separation from the flight envelope is large, so the parachute 51 is ejected.

[0099] [3] In some cases, if the MCU 141 determines based on the detection result of the inertial device 142 that the flight state has changed from the stable flight state within the flight envelope (reference range) to the first departure flight state (for example, Fig. 9 The first total value of the dependent variable value (Va(P1)) of the function Va(x) based on the first flight state of separation and the dependent variable value (Vb(Tp1)) of the function Vb(t) based on the duration Tp of the separation state that is greater than the separation degree of the first flight state of separation is calculated. If the first total value exceeds the threshold value (in this example, 1), the MCU 141 causes the ejection device 5 to eject the parachute 51.

[0100] [4] In another certain situation, if the MCU 141 determines based on the detection result detected by the inertial device 142 that the flight state has further changed from the first escape flight state to a second escape flight state that is more escaped from the flight envelope than the first escape flight state (for example, Fig. 9 The following processing is performed if the state of the combined acceleration P2 is shown.

[0101] MCU 141 calculates the first total value again. Furthermore, MCU 141 calculates the second total value of the value of the dependent variable (Va(P2)) of the function Va(x) based on the second flight state departure and the value of the dependent variable (Vb(Tp2)) of the function Vb(t) based on the duration (Tp2) of the departure state that is greater than the departure degree of the second flight state departure.

[0102] If at least one of the first total value and the second total value exceeds a threshold value (in this example, 1), the MCU 141 causes the ejection device 5 to eject the parachute 51 .

[0103] [5] In the above, the case where the flight state changes from the stable flight state to the first departure flight state and the case where the flight state changes from the stable flight state via the first departure flight state to the second departure flight state are cited as examples for explanation, but the present invention is not limited to these.

[0104] When the flight states are the first departure flight state, the second departure flight state, …, the n-th departure flight state (n is a natural number greater than or equal to 3) and the degree of departure increases in sequence, the MCU 141 performs the following processing. Further, hereinafter, let k be any natural number greater than or equal to 3 and less than or equal to n.

[0105] If the MCU 141 determines that the flight state changes from the (k - 1)-th departure flight state to the k-th departure flight state where the flight envelope is departed from to a greater extent than the (k - 1)-th departure flight state, the k-th total value of the dependent variable value of the function Va(x) based on the k-th departure flight state and the dependent variable value of the function Vb(t) based on the duration of the departure state equal to or greater than the degree of departure of the k-th departure flight state is calculated. Further, when the flight state changes in such a manner that the degree of departure increases in sequence from the first departure flight state to the n-th departure flight state, if at least one of the n total values from the first total value to the n-th total value exceeds the threshold value, the ejection device 5 ejects the parachute 51.

[0106] 〔6〕The function Va(x) and the function Vb(t) are membership functions. The above-mentioned threshold value is 1. The range of the dependent variable value of the function Va(x) is 0 or more and less than 1. The range of the dependent variable value of the function Vb(t) is 0 or more and less than 1. According to such a configuration, the value of the function Va(x) and the value of the function Va(x) do not exceed 1 separately. Therefore, in the unmanned aerial vehicle 1, it is possible to prevent the case where the parachute 51 is ejected at the degree of departure from the flight envelope and the case where the parachute 51 is ejected at the duration of departure.

[0107] <G. Modification Example> (1) In the above, as an example of the flight state, the combined acceleration of the unmanned aerial vehicle 1 is cited for explanation. However, it is not limited thereto. The flight state may also be any one of the change in height per unit time of the unmanned aerial vehicle 1, the roll angle of the unmanned aerial vehicle 1, the roll angular velocity of the unmanned aerial vehicle 1, the pitch angle of the unmanned aerial vehicle 1, the pitch angular velocity of the unmanned aerial vehicle 1, and the yaw angular velocity of the unmanned aerial vehicle 1.

[0108] Regarding each flight state, preferably, a pair of functions (i) the first function that uses, as a function with the flight state as the independent variable, and the dependent variable value is proportional to the degree of departure of the flight state departing from the reference range (flight envelope) determined for the flight state and (ii) the second function that uses, as a function with the duration of departure as the independent variable, and the dependent variable value is proportional to the duration is used to determine whether to eject the parachute 51.

[0109] (2) In the above, the MCU 141 of the trigger device 14 uses the function Va(x) and the function Vb(t) to determine whether to eject the parachute 51 from the ejection device 5. However, the present invention is not limited to this. Alternatively, the MCU 81 of the flight controller 8 may store the function Va(x) and the function Vb(t), and the flight controller 8 may use the function Va(x) and the function Vb(t) instead of the trigger device 14 to determine whether to eject the parachute 51 from the ejection device 5.

[0110] (3) The MCU 141 of the trigger device 14 may calculate the combined acceleration and speed based on the detection value detected by the barometric altimeter 143 .

[0111] In addition, these three modified examples (1) to (3) are also applicable to the drone in the second embodiment described later.

[0112] [Implementation Method 2] In this embodiment, a configuration that can reduce the amount of calculation of the MCU 141 compared to Embodiment 1 is described. In this embodiment, points different from Embodiment 1 are described, and the same points are not described repeatedly.

[0113] In this embodiment, the function Va'(x) is stored instead of the function Va(x). The function Vb'(t) is stored instead of the function Vb(t). Specifically, the memory 1411 stores the data table DT( Fig.14 ). In the data table DT, there are functions Va'(x) and Vb'(t).

[0114] Hereinafter, first, the functions Va'(x), Vb'(t) and the data table DT will be described. Next, the determination process using the functions Va'(x), Vb'(t) and the data table DT will be described.

[0115] Fig.12 is a graph showing the function Va'(x). Fig.12 As shown, the function Va'(x) is similar to the function Va'(x) of the first embodiment, and is a function that takes the flight state of the drone 1 (specifically, the synthetic acceleration) as the independent variable (i.e., x), and the value of the dependent variable (i.e., y) is proportional to the degree of departure of the flight state from the reference range (flight envelope) determined for the flight state. In the present embodiment, the range of the value of the dependent variable of the function Va'(x) is also greater than 0 and less than 1. That is, the value of the dependent variable of the function Va'(x) will not be greater than 1.

[0116] Specifically, the function Va'(x) is a step function. In the function Va'(x), the range of x is 3.75 m / s 2 Above and 5.75m / s 2In the following range, the value of y is proportional to the degree of departure from the flight envelope in a step-like manner. Function Va'(x) is 3.75 m / s 2 Above and 5.75m / s 2 The following range becomes a step-like shape.

[0117] In the function Va'(x), similarly to the function Va(x) in the first embodiment, the resultant acceleration is set to 5.75 m / s 2 The value of the function is 0.1, making the resultant acceleration 3.75m / s 2 The value of the function at 5.75 m / s is 0.9. 2 "It is Figure 6 The lower limit of the combined acceleration described in .

[0118] In the x range of 3.75m / s 2 Above and 5.75m / s 2 In the range below 3.75 m / s, the value of y increases to the extent that the flight state deviates from the flight envelope (the difference between x and 5.75). 2 Above and 5.75m / s 2 Specific examples of the values ​​of the functions in the following ranges are shown in the data table DT.

[0119] Fig.13 is a graph showing the function Vb'(t). Fig.13 As shown, the function Vb'(t) is similar to the function Vb(t) of the first embodiment, and is a function that takes the duration of departure from the flight envelope as the independent variable (x), and the value of the dependent variable (y) is proportional to the duration. The value range of the dependent variable of the function Vb'(t) is greater than 0 and less than 1. That is, the value of the dependent variable of the function Vb'(t) will not be greater than 1.

[0120] Specifically, the function Vb'(t) is a step function. In the range of x from 0.1s to 0.5s, the value of y is proportional to the degree of departure from the flight envelope in a step-like manner. The function Vb'(t) is in a step-like manner in the range of 0.1s to 0.5s.

[0121] In function Vb'(t), the function value is set to 0.1 when the duration is 0.1s, and the function value is set to 0.9 when the duration is 0.5s, similarly to function Vb(t) in embodiment 1. Specific examples of function values ​​in the range of 0.1s to 0.5s are shown in data table DT.

[0122] Fig.14 DT is a diagram showing a data table DT. Fig.14 As shown, the data table DT includes a function Va'(x) and a function Vb'(t).

[0123] Specifically, regarding the function Va'(x), the data table DT includes 3.75 m / s 2 Above and 5.75m / s 2 The threshold values ​​of each resultant acceleration (x) and the value of the function (Va'(x)) corresponding to each resultant acceleration (x) are as follows. In this example, the decrease (step width) of the resultant acceleration (x) is 0.05 m / s 2 .

[0124] Regarding the function Vb'(t), the data table DT includes threshold values ​​of duration (t) in the range of 0.1 s to 0.5 s and function values ​​(Vb'(t)) corresponding to each duration (t). In this example, the duration (t) decreases by 0.01 s.

[0125] In the data table DT, as shown in patterns #1 to #41, a plurality of combinations of threshold values ​​of combined acceleration (x) and duration (t) for which the sum of (Va'(x)) and the function value (Vb'(t)) becomes 1 are stored.

[0126] The MCU 141 refers to the data table DT to determine whether the parachute 51 should be launched. Specifically, the MCU 141 refers to a plurality of combinations of the thresholds of the combined acceleration (x) and the duration (t) shown in patterns #1 to #41 to determine whether the parachute 51 should be launched.

[0127] Fig.15 is a flowchart for explaining the flow of processing performed in a certain situation. Fig.15 Each step S11 to S14 in the process is repeatedly executed in each predetermined control cycle (for example, every 0.01 seconds).

[0128] In step S11, the MCU 141 of the trigger device 14 obtains the resultant acceleration P from the inertial device 142. In step S12, the MCU 141 compares the resultant acceleration P with the thresholds of multiple resultant accelerations (x) with reference to the data table DT, and obtains the threshold smaller than the resultant acceleration P and closest to the duration (t) of the resultant acceleration P.

[0129] For example, the MCU 141 obtains 5.75 m / s in step S1. 2(hereinafter also referred to as "composite acceleration P3") as the composite acceleration (x), as shown in pattern #1, 0.5s (hereinafter also referred to as "threshold Tp3") is obtained as the threshold of duration (t) in step S2. Similarly, MCU 141 obtains 5.73m / s in step S1. 2 In the case of the combined acceleration (x), as shown in pattern #1, 0.5 s (threshold value Tp3) is acquired as the threshold value of the duration (t) in step S2.

[0130] The MCU 141 obtains 5.7 m / s in step S1. 2 (hereinafter also referred to as "composite acceleration P4") as the composite acceleration (x), as shown in pattern #2, 0.49s (hereinafter also referred to as "threshold Tp4") is obtained as the threshold of duration (t) in step S2. Similarly, MCU 141 obtains 5.68m / s in step S1. 2 In the case of the combined acceleration (x), as shown in pattern #2, 0.46 s (threshold value Tp4) is acquired as the threshold value of the duration (t) in step S2.

[0131] In step S13, the MCU 141 determines whether the duration of the state below the combined acceleration P is greater than or equal to a threshold value of a duration t corresponding to the combined acceleration P. For example, when the MCU 141 obtains the combined acceleration P3 in step S11, the MCU 141 determines whether the duration of the state below the combined acceleration P3 is greater than or equal to a threshold value Tp3 of a duration t corresponding to the combined acceleration P3.

[0132] In addition, after continuously obtaining the resultant acceleration P3 in step S11 over at least one control cycle, the MCU 141 continuously obtains the resultant acceleration P4 in step S11 over at least one control cycle, and then performs the following processing. That is, the MCU 141 determines whether the duration of the state below the resultant acceleration P3 is greater than or equal to the threshold value Tp3 of the duration t corresponding to the resultant acceleration P3, and whether the duration of the state below the resultant acceleration P4 is greater than or equal to the threshold value Tp4 of the duration t corresponding to the resultant acceleration P4.

[0133] If a positive determination is made in step S13 (Yes in step S13), the MCU 141 transmits a command to the trigger device 14 in step S14, so that the ejection device 5 ejects the parachute 51. If a negative determination is made in step S13 (No in step S13), the MCU 141 transfers to the next control cycle and executes step S11 again.

[0134] In addition, in order to simplify the description, only the transition from the combined acceleration P3 to the combined acceleration P4 is shown. For example, if after the transition to the combined acceleration P4, the combined acceleration P5 is smaller than the combined acceleration P4 and becomes the type #3 or later, the determination process of the use duration is performed for each of the three combined accelerations P3, P4, and P5. Fig.15 The duration of use is determined for each of the types (each category) shown.

[0135] <Conclusion> The drone 1 according to this embodiment can be summarized as follows.

[0136] [1] Similar to Embodiment 1, the drone 1 comprises: an inertial device 142 for detecting the flight state of the drone 1; an ejection device 5 including a parachute 51 and capable of ejecting the parachute 51; and an MCU (controller) 141 for determining whether it is necessary to eject the parachute 51 based on the degree of departure of the flight state from a reference range (i.e., a flight envelope) determined for the flight state and the duration of the departure state above the degree of departure.

[0137] [2] MCU 141 stores function Va'(x) and function Vb'(t). Function Va'(x) is a function with the flight state as an independent variable, and the value of the dependent variable is proportional to the degree of departure from the flight envelope. Function Vb'(t) is a function with the duration of departure as an independent variable, and the value of the dependent variable is proportional to the duration.

[0138] If the MCU 141 determines that the total value of the dependent variable of the function Va'(x) and the dependent variable of the function Vb'(t) during the flight of the drone 1 exceeds a predetermined threshold (in this example, 1), the ejection device 5 ejects the parachute 51.

[0139] According to such a configuration, whether or not the parachute 51 needs to be launched can be determined based on the degree of departure from the flight envelope and the duration of the departure state exceeding the degree of departure, and the parachute 51 can be launched based on the determination result.

[0140] [3] Function Va'(x) and function Vb'(t) are step functions. As shown in the data table DT, the MCU 141 generates a first flight state (for example, a synthetic acceleration of 5.75 m / s) out of the flight envelope (reference range) among the plurality of flight states. 2) and the total value of the value of the dependent variable of function Va'(x) (e.g., 0.1) and the value of the dependent variable of function Vb'(t) reaches a threshold value (in this example, 1) and the first duration of disengagement (e.g., a threshold value of 0.5 seconds) is pre-stored in association with the first disengagement flight state.

[0141] In some cases, the MCU 141 changes from a stable flight state within the flight envelope to a first escape flight state (eg, a synthetic acceleration of 5.75 m / s 2 ), if the duration of the separation state above the separation degree of the first separation flight state exceeds the first duration (for example, 0.5 seconds), the ejection device 5 ejects the parachute 51.

[0142] [4] The MCU 141 sets the second departure flight state (for example, a resultant acceleration of 5.7 m / s) which is greater than the first departure flight state among the plurality of flight states and which departs from the flight envelope to a greater extent. 2 ) and the second duration of disengagement (e.g., threshold value 0.49 seconds) when the total value of the dependent variable of function Va'(x) (e.g., 0.12) and the dependent variable of function Vb'(t) reaches a threshold (in this example, 1) is stored in association with the second disengagement flight state.

[0143] In some cases, when the flight state changes from the first escape flight state to the second escape flight state, the MCU 141 causes the ejection device 5 to eject the parachute 51 when any of the following first and second conditions are satisfied. The first condition is that the duration of the escape state exceeding the degree of the first escape flight state exceeds the first duration (threshold value 0.5 seconds). The second condition is that the duration of the escape state exceeding the degree of the second escape flight state exceeds the second duration (threshold value 0.49 seconds).

[0144] With this configuration, similarly to the first embodiment, it is possible to determine whether or not the parachute 51 needs to be launched based on the degree of departure from the flight envelope and the duration of the departure state exceeding the degree of departure, and to launch the parachute 51 based on the determination result.

[0145] Furthermore, the threshold of the duration (t) is made to correspond to each threshold of the synthetic acceleration (x). Therefore, it is not necessary to successively calculate the sum of the value of the dependent variable of the function Va'(x) (the value of the function) and the value of the dependent variable of the function Vb'(t) (the value of the function). Therefore, compared with the first embodiment, the amount of calculation processing of the MCU 141 can be reduced.

[0146] [5] In the above, the case where the flight state changes from the stable flight state to the first escape flight state and the case where the flight state changes from the stable flight state via the first escape flight state to the second escape flight state are cited as examples for explanation, but the present invention is not limited to this. In addition, in the following, n is a natural number greater than 3, and k is an arbitrary natural number greater than 3 and less than n.

[0147] The MCU 141 associates and stores the kth duration of the separation, in which the total value of the value of the dependent variable of the function Va'(x) and the value of the dependent variable of the function Vb'(t) reaches a threshold value, with the kth separation flight state based on the kth separation flight state that separates from the flight envelope to a greater extent than the k-1th separation flight state among the multiple flight states. When the flight state changes from the first separation flight state to the nth separation flight state in a manner where the degree of separation increases successively, the MCU 141 causes the ejection device 5 to eject the parachute 51 when any one of the first to nth conditions is satisfied.

[0148] As described above, the first condition is that the duration of the separation state exceeding the separation degree of the first separation flight state exceeds the first duration. As described above, the second condition is that the duration of the separation state exceeding the separation degree of the second separation flight state exceeds the second duration. The kth condition (the third to nth conditions) is that the duration of the separation state exceeding the separation degree of the kth separation flight state exceeds the kth duration.

[0149] <Notes> (1) An aircraft, which is an aircraft, having: A sensor device for detecting the flight status of the aforementioned aircraft; a controller storing a first function and a second function; and an ejection device, which includes a parachute and is capable of ejecting the parachute, The first function is a function having the flight state as an independent variable, and a value of the dependent variable is proportional to the degree of deviation of the flight state from a reference range determined for the flight state. The second function is a function with the duration of the separation as the independent variable, and the value of the dependent variable is proportional to the duration. If the controller determines that the total value of the value of the dependent variable of the first function and the value of the dependent variable of the second function when the aircraft is flying exceeds a predetermined threshold value, the controller causes the ejection device to eject the parachute.

[0150] (2) A method for controlling an aircraft, which is a method for controlling an aircraft capable of ejecting a parachute, The aircraft stores a first function and a second function, wherein the first function is a function with the flight state of the aircraft as an independent variable, and the value of the dependent variable is proportional to the degree of departure of the flight state from a reference range determined for the flight state, and the second function is a function with the duration of the departure as an independent variable, and the value of the dependent variable is proportional to the duration. The control method of the above-mentioned aircraft has the following features: The step of detecting the flight status of the aforementioned aircraft; and The following steps: if it is determined that the total value of the value of the dependent variable of the first function and the value of the dependent variable of the second function when the aircraft is flying exceeds a predetermined threshold value, then the parachute is launched.

[0151] The embodiments disclosed this time are illustrative and are not limited to the above contents. The scope of the present invention is indicated by the claims, and all modifications within the meaning and scope equivalent to the claims are intended to be included. Description of Reference Numerals

[0152] 1 UAV, 2 main body, 3A, 3B, 3C, 3D arms, 4A, 4B, 4C, 4D propulsion mechanism, 5 injection device, 6 communication unit, 7A, 7B, 7C, 7D driving device, 8 flight controller, 9, 13 battery, 10 power module, 12 distributor, 14 trigger device, 15 sensor, 16 GNSS receiver, 18 support component, 41 propeller, 42 motor, 51 parachute, 82, 142 inertial device, 83, 143 barometric altimeter, 900 remote controller, 910, 920 joystick, 1411 memory, 1412 judgment unit, 1421 gyroscope, 1422 accelerometer, 1423 processor, DT data table, W1, W2, W3 waveform.

Claims

1. An aircraft, which is an aircraft, having: A sensor device for detecting the flight status of the aircraft; an ejection device, which includes a parachute and is capable of ejecting the parachute; and A controller determines whether or not it is necessary to eject the parachute based on a degree of departure of the flight state from a reference range determined for the flight state and a duration of time during which a departure state exceeding the degree of departure continues.

2. The aircraft according to claim 1, wherein: The controller stores a first function and a second function, The first function is a function that uses the flight state as an independent variable, and the value of the dependent variable is proportional to the degree of departure of the flight state from the reference range. The second function is a function with the duration of the separation as an independent variable, and the value of the dependent variable is proportional to the duration, The controller causes the ejection device to eject the parachute if the controller determines that the total value of the dependent variable of the first function and the dependent variable of the second function when the aircraft is flying exceeds a predetermined threshold value.

3. The aircraft according to claim 2, wherein: The controller: If it is determined based on the detection result detected by the sensor device that the flight state has changed from a stable flight state within the reference range to a first departure flight state that has departed from the reference range, a first total value of a value of a dependent variable of the first function based on the first departure flight state and a first total value of a value of a dependent variable of the second function based on a duration of a departure state that is greater than the departure degree of the first departure flight state is calculated, If the first total value exceeds the threshold value, the ejection device is caused to eject the parachute.

4. The aircraft according to claim 3, wherein: The controller: If it is determined based on the detection result detected by the sensor device that the flight state has further changed from the first departure flight state to the second departure flight state that is more departure from the reference range than the first departure flight state, the first total is calculated again, and a second total value of the value of the dependent variable of the first function based on the second departure flight state and the value of the dependent variable of the second function based on the duration of the departure state exceeding the departure degree of the second departure flight state is calculated, If at least one of the first total value and the second total value exceeds the threshold value, the ejection device is caused to eject the parachute.

5. The aircraft according to claim 4, wherein: If n is a natural number greater than 3, and k is an arbitrary natural number greater than 3 and less than n, Then the controller: If it is determined that the flight state has further changed from the k-1th flight state to the kth flight state that has deviated from the reference range to a greater extent than the k-1th flight state, the kth total value of the value of the dependent variable of the first function based on the kth flight state and the value of the dependent variable of the second function based on the duration of the separation state exceeding the degree of separation of the kth flight state is calculated, When the flight state changes from the first separation flight state to the nth separation flight state with the degree of separation increasing successively, if at least one of the n total values ​​from the first total value to the nth total value exceeds the threshold value, the ejection device ejects the parachute.

6. An aircraft according to any one of claims 2 to 5, wherein: The first function and the second function are membership functions, The threshold is 1, The range of the value of the dependent variable of the first function is greater than or equal to 0 and less than 1, The range of the value of the dependent variable of the second function is greater than or equal to 0 and less than 1.

7. The aircraft according to claim 2, wherein: The first function and the second function are step functions, The controller: Pre-storing a first duration of the departure in which the total value of the dependent variable of the first function and the dependent variable of the second function reaches the threshold value based on a first departure flight state out of the reference range among the plurality of flight states, in association with the first departure flight state, When the flight state changes from the stable flight state within the reference range to the first escape flight state, if the escape state exceeding the escape degree of the first escape flight state continues for a duration exceeding the first duration, the ejection device ejects the parachute.

8. The aircraft according to claim 7, wherein: The controller: The second duration of the departure, in which the total value of the value of the dependent variable of the first function and the value of the dependent variable of the second function based on a second departure from the reference range that is more departed from the first departure from the flight state among the plurality of flight states reaches the threshold, is associated with the second departure from the flight state and stored; When the flight state changes from the first breakaway flight state to the second breakaway flight state, when either the first condition or the second condition is satisfied, the ejection device ejects the parachute; The first condition is that the duration of the separation state that is greater than the separation degree of the first separation flight state exceeds the first duration, The second condition is that a separation state equal to or greater than the separation degree of the second separation flight state continues for a duration exceeding the second duration.

9. The aircraft according to claim 8, wherein: If n is a natural number greater than 3, and k is an arbitrary natural number greater than 3 and less than n, Then the controller: storing, in association with the kth departure flight state, a kth duration of departure based on a kth departure flight state that departs from the reference range to a greater extent than the k-1th departure flight state among the plurality of flight states, wherein the total value of the value of the dependent variable of the first function and the value of the dependent variable of the second function reaches the threshold, When the flight state changes from the first escaped flight state to the nth escaped flight state in a manner in which the degree of escape increases successively, the ejection device ejects the parachute when any one of the first to nth conditions is satisfied, The kth condition is that the duration of the separation state that is greater than the kth separation degree from the flight state continues exceeds the kth duration.

10. The aircraft according to claim 1, wherein: The reference range is the flight envelope of the aircraft, The flight state is any one of the acceleration of the aircraft, the change in altitude of the aircraft per unit time, the roll angle of the aircraft, the roll angular velocity of the aircraft, the pitch angle of the aircraft, and the pitch angular velocity of the aircraft.

11. A method for controlling an aircraft, which is a method for controlling an aircraft capable of ejecting a parachute, comprising: a step of detecting the flight status of the aircraft; and A step of determining whether or not it is necessary to eject the parachute based on a degree of departure of the flight state from a reference range determined for the flight state and a duration of a departure state exceeding the degree of departure.

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