Flying body guidance system, flying body, flying body management device, and flying body guidance method

Abstract

This flying body guidance system comprises: a flying body detection unit that calculates a ground measured position / speed (see position / speed (613)), which is a position or speed of a flying body, on the basis of the output of at least one of a camera and a radar installed on the ground; a position calculation unit that calculates a flying body measured position / speed (see position / speed (615)), which is a position or speed of the flying body, on the basis of the output value of an inertial measurement device (381) mounted on the flying body; and an inertial measurement device correction unit that calculates at least one of the bias and drift of the inertial measurement device (381) (see bias / drift (631) of inertial measurement device (381)) on the basis of the ground measured position / speed and the flying body measured position / speed.

Description

Aircraft guidance system, aircraft, aircraft management device, and aircraft guidance method

[0001] The present invention relates to an air vehicle guidance system for guiding an unmanned aerial vehicle, an air vehicle, an air vehicle management device, and an air vehicle guidance method.

[0002] With the widespread use of unmanned aerial vehicles and the lifting of the ban on autonomous flight beyond visual line of sight following the enforcement of the revised Aviation Act, the use of unmanned aerial vehicles for delivery of goods is expected to become widespread, including in urban areas. Safe and compliant use of unmanned aerial vehicles requires accurate guidance of the unmanned aerial vehicles. An autonomous mobility control system, as described in Patent Document 1, is an example of a guidance system for unmanned aerial vehicles.

[0003] This autonomous movement control system includes a traveling device and an unmanned aerial vehicle capable of wireless communication. The unmanned aerial vehicle performs autonomous movement control when moving. The traveling device includes an imaging means for imaging the unmanned aerial vehicle, a determining means for determining position information or orientation information of the unmanned aerial vehicle from the image of the unmanned aerial vehicle captured by the imaging means, and a transmitting means for transmitting the position information or orientation information of the unmanned aerial vehicle as a control signal to the unmanned aerial vehicle. The unmanned aerial vehicle includes a receiving means for receiving the control signal from the traveling device and a movement control means for performing autonomous movement control of the unmanned aerial vehicle based on the received control signal.

[0004] JP 2018-005914 A

[0005] According to the autonomous movement control system described in Patent Document 1, an unmanned aerial vehicle can perform autonomous movement control based on a received control signal. However, in rainy or cloudy weather, the unmanned aerial vehicle blends into the background, making it difficult for the traveling device to accurately determine the position and orientation information of the unmanned aerial vehicle using camera images, which may make accurate autonomous movement control difficult. The present invention has been made in light of this background, and aims to provide an air vehicle guidance system, an air vehicle, an air vehicle management device, and an air vehicle guidance method that enable highly accurate guidance of an unmanned aerial vehicle.

[0006] In order to solve the above-mentioned problems, the aircraft guidance system device of the present invention comprises an aircraft detection unit that calculates the ground-measured position velocity, which is the position or velocity of the aircraft, based on the output of at least one of a camera and a radar installed on the ground, a position calculation unit that calculates the aircraft-measured position velocity, which is the position or velocity of the aircraft, based on the output value of an inertial measurement unit mounted on the aircraft, and an inertial measurement unit correction unit that calculates at least one of the bias and drift of the inertial measurement unit based on the ground-measured position velocity and the aircraft-measured position velocity.

[0007] According to the present invention, it is possible to provide an air vehicle guidance system, an air vehicle, an air vehicle management device, and an air vehicle guidance method that enable highly accurate guidance of an unmanned aerial vehicle. Problems, configurations, and effects other than those described above will become clear from the description of the following embodiments.

[0008] Fig. 1 is a diagram showing the overall configuration of an aircraft guidance system according to the present embodiment. Fig. 2 is a functional block diagram of an aircraft management device according to the present embodiment. Fig. 3 is a functional block diagram of an aircraft according to the present embodiment. Fig. 4 is a diagram for explaining the processing contents of a control unit of an aircraft according to the present embodiment. Fig. 5 is a diagram for explaining the processing contents of a control unit of an aircraft according to the present embodiment. Fig. 6 is a hardware configuration diagram showing an example of a computer that realizes the functions of the aircraft management device and aircraft according to the above-mentioned embodiment.

[0009] <<Outline of Aircraft Guidance System>> An aircraft guidance system in a mode (embodiment) for carrying out the present invention will be described below. The aircraft guidance system includes an aircraft and an aircraft management device that guides and controls the aircraft to manage its flight. The aircraft management device detects the position and speed of the aircraft using radar and a camera and transmits the information to the aircraft.

[0010] An aircraft calculates its own position and velocity based on the output values ​​(acceleration and angular velocity) of the inertial measurement unit it is equipped with, its position based on satellite positioning, and the position and velocity received from the aircraft management unit. The aircraft also calculates the bias and drift of the inertial measurement unit based on the position and velocity calculated from the output values ​​of the inertial measurement unit and the position and velocity received from the aircraft management unit, and uses this for correction. Using the inertial measurement unit, an aircraft can determine its own position even in mountainous areas, as well as in places where satellites are not visible due to high-rise buildings or bridges. The change in position per unit time is velocity.

[0011] Furthermore, the aircraft calculates parameters of the aerodynamic model so that the speed received from the aircraft management device matches the speed calculated from the acceleration calculated using the aerodynamic model based on the rotational speed of the propeller.The aircraft calculates the surrounding wind speed based on its own speed and the speed calculated using the aerodynamic model based on the rotational speed of the propeller.The aircraft uses this wind speed to control flight so as to follow the flight path.This flight guidance system enables highly accurate guidance of the aircraft.

[0012] <Overall Configuration of Aircraft Guidance System> FIG. 1 is a diagram showing the overall configuration of an aircraft guidance system 10 according to this embodiment. The aircraft guidance system 10 includes an aircraft management device 200 and an aircraft 300. The aircraft guidance system 10 may also include a radar 510, a camera 520, and a weather sensor 530 connected to the aircraft management device 200. The aircraft 300 and the aircraft management device 200 can communicate wirelessly via a communication antenna 540. The radar 510, the camera 520, and the weather sensor 530 are not necessarily installed at or near the airport 580. For example, a camera 521 installed on a building or streetlight that is part of a smart infrastructure may capture an image of the aircraft 300. The installation positions and orientations of the radar 510 and the cameras 520 and 521 are specified, and the position of the captured aircraft 300 can be calculated.

[0013] <Configuration of Air Vehicle Management Device> Figure 2 is a functional block diagram of an air vehicle management device 200 according to this embodiment. The air vehicle management device 200 is a computer, and includes a control unit 210, a storage unit 220, and an input / output unit 280. User interface devices such as a display, keyboard, and mouse are connected to the input / output unit 280. The input / output unit 280 also includes a communication device, and is capable of transmitting and receiving data to and from the radar 510, cameras 520 and 521, weather sensor 530, and air vehicle 300.

[0014] <Air Vehicle Management Device: Storage Unit> The storage unit 220 includes storage devices such as a read-only memory (ROM), a random access memory (RAM), a solid-state drive (SSD), etc. The storage unit 220 stores an air vehicle information database 230, a flight information database 240, an environmental information database 250, and a program 228.

[0015] The air vehicle information database 230 stores information related to each air vehicle 300, such as identification information, manufacturer, model, and specifications. Specifications include size, weight, maximum flight speed, maximum altitude, maximum wind resistance, maximum flight time, and maximum payload.

[0016] The flight information database 240 stores information related to each flight of the flying object 300, such as the identification information of the flying object 300, the departure point, the destination, the payload, its weight, the scheduled departure date and time, the scheduled arrival date and time, and the planned flight route. The flight information database 240 also stores the departure date and time, the arrival date and time, and the flight route as a flight record. The flight record may also include meteorological information, including wind speed along the flight route.

[0017] The environmental information database 250 stores weather information for the area in which the flying object 300 flies. The program 228 includes a description of the processing of each functional unit provided in the control unit 210, which will be described later. Note that databases such as the flying object information database 230 and the flight information database 240 do not necessarily have to be provided in the flying object management device 200, but may exist on a cloud server.

[0018] <Aircraft Management Device: Control Unit> The control unit 210 includes a CPU (Central Processing Unit), and is equipped with an environmental information acquisition unit 211, an aircraft detection unit 212, a flight path calculation unit 213, and an aircraft control unit 214.

[0019] <<Air Vehicle Management Device: Environmental Information Acquisition Unit>> The environmental information acquisition unit 211 acquires meteorological information for the area in which the air vehicle 300 flies and stores it in the environmental information database 250. The source of the meteorological information is not limited to the weather sensor 530, but may also be a weather information provider. The environmental information acquisition unit 211 may also acquire information from the weather information provider, including a future weather forecast for the planned flight.

[0020] <<Flying Object Management Device: Flying Object Detection Unit>> The flying object detection unit 212 repeatedly detects flying objects 300 included in images acquired by the radar 510 and cameras 520 and 521, and stores their positions and speeds together with time in the flight information database 240. To explain in more detail, the flying object detection unit 212 calculates the speed (direction and speed of movement) based on time-series data of the positions at which the flying object 300 is detected.

[0021] The flight information database 240 stores the position and speed of the flying object 300 notified by the flying object 300. If the position of the flying object 300 detected from images of the radar 510 or cameras 520 and 521 is close to the position notified by the flying object 300 (if the difference is equal to or less than a predetermined value), the flying object detection unit 212 regards the identification information of the detected flying object 300 as the identification information of the notified flying object 300.

[0022] As described above, the aircraft guidance system 10 (aircraft management device 200) is equipped with an aircraft detection unit 212 that calculates the ground-measured position and velocity (see position / velocity 613 described below), which is the position or velocity of the aircraft 300, based on the output of at least one of the cameras 520, 521 and radar 510 installed on the ground.

[0023] <<Flying Object Management Device: Flight Path Calculation Unit>> The flight path calculation unit 213 calculates a planned flight path for a future flight in the flight information database 240 and stores it in the flight information database 240. At this time, the flight path calculation unit 213 may calculate a route that avoids no-fly zones and areas (airspace) where congestion of the flying object 300 is expected. Furthermore, if the wind speed on the route is high and the flight time is expected to be long, the flight path calculation unit 213 may change the planned departure time and calculate the route.

[0024] <<Aircraft Management Device: Aircraft Control Unit>> The aircraft control unit 214 receives the position and speed of the aircraft 300 notified by the aircraft 300 at a predetermined cycle, and stores the information in the flight information database 240. The aircraft control unit 214 also repeatedly notifies the aircraft 300 of the position and speed of the aircraft 300 detected by the aircraft detection unit 212. Furthermore, the aircraft control unit 214 obtains meteorological information including wind speed at the position of the aircraft 300 from the environmental information database 250, and notifies the aircraft 300 at a predetermined cycle.

[0025] <Configuration of Air Vehicle> Figure 3 is a functional block diagram of an air vehicle 300 according to this embodiment. The air vehicle 300 is a computer capable of flight, and includes a control unit 310, a memory unit 320, and a sensor antenna 380. The air vehicle 300 also includes a propeller as a thrust device, a motor for driving the propeller, a power source, and the like, but these are not shown in Figure 3. The sensor antenna 380 includes an inertial measurement unit 381 and a GNSS antenna 382 (Global Navigation Satellite System antenna). The sensor antenna 380 also includes a communication antenna, a magnetic direction sensor, a barometric pressure sensor, and the like, but these are not shown in Figure 3.

[0026] <<Air Vehicle: Storage Unit>> The storage unit 320 is configured to include storage devices such as ROM, RAM, and flash memory. The storage unit 320 stores air vehicle information 330, flight path information 340, and a program 328. The program 328 includes a description of the processing of each functional unit provided in the control unit 310, which will be described later.

[0027] The aircraft information 330 stores the identification information, manufacturer, model, specifications, etc. of the aircraft 300 itself. In addition, the aircraft information 330 stores parameters of an aerodynamic model of the aircraft 300, which will be described later.

[0028] The flight route information 340 stores the flight departure point, destination, payload, its weight, scheduled departure date and time, scheduled arrival date and time, planned flight route, etc. The flight route information 340 also stores the departure date and time, arrival date and time, flight route, etc. as a flight record. The flight record may also include meteorological information such as wind speed along the flight route.

[0029] <<Air Vehicle: Control Unit>> The control unit 310 includes a CPU and is equipped with a position calculation unit 311, an inertial measurement unit correction unit 312, a model parameter calculation unit 313, an environmental value calculation unit 314, a flight control unit 315, and a communication unit 316. Each of these functional units repeatedly executes the processing described below.

[0030] 4 is a diagram for explaining the processing contents of the control unit 310 of the flying body 300 according to this embodiment. The position calculation unit 311, the inertial measurement unit correction unit 312, and the model parameter calculation unit 313 will be explained below with reference to FIG.

[0031] <<Air Vehicle: Position Calculation Unit>> The position calculation unit 311 calculates the position and velocity of the air vehicle 300. The position calculation unit 311 calculates the velocity (including the direction) based on the acceleration and angular velocity 611 (acceleration and angular velocity by inertial navigation) of the air vehicle 300 output by the inertial measurement unit 381, and further calculates the position of the air vehicle 300 based on this velocity to obtain the position and velocity 615 (position and velocity by inertial navigation). Note that the acceleration and angular velocity 611 are not the output values ​​(measurement values) of the inertial measurement unit 381 themselves, but are the acceleration and angular velocity from which a bias (see bias drift 631 of the inertial measurement unit 381) described below has been subtracted.

[0032] The position calculation unit 311 calculates the position 612 (position by satellite navigation) of the flying object 300 based on the output of the GNSS antenna 382. If the flying object 300 is detected in images from the radar 510 or cameras 520 and 521, the flying object management device 200 transmits the position and velocity 613 of the flying object 300 (position and velocity from the flying object management device 200) to the flying object 300. The position calculation unit 311 acquires this position and velocity 613 via the communication unit 316 described below. In addition, the position calculation unit 311 calculates the velocity 614 of the flying object 300 (velocity according to the aerodynamic model) using an aerodynamic model based on the rotational speed of the propeller of the flying object 300 controlled by the flight control unit 315 described below.

[0033] The position calculation unit 311 calculates the position and velocity 621 of the flying object 300 based on the acceleration and angular velocity 611 (acceleration and angular velocity by inertial navigation), position 612 (position by satellite navigation), position and velocity 613 (position and velocity from the flying object management device 200), velocity 614 (velocity by aerodynamic model), and position and velocity 615 (position and velocity by inertial navigation). This will be explained below.

[0034] For example, when the position / velocity 613 cannot be received from the flying object management device 200, the position calculation unit 311 calculates the position / velocity 621 using a Kalman filter based on the acceleration / angular velocity 611 and the position 612. When the position / velocity 613 can be received, the position calculation unit 311 calculates the position / velocity 621 using a Kalman filter based on, for example, the acceleration / angular velocity 611 and the position / velocity 613. The value of the Kalman gain may be changed depending on whether the position 612 or the position / velocity 613 is referenced as an observation value.

[0035] Alternatively, the position calculation unit 311 may calculate the position by combining the position 612 and the position / velocity 613, and may use a Kalman filter to calculate the position / velocity 621 based on this and the acceleration / angular velocity 611. Furthermore, the position calculation unit 311 may use a method other than the Kalman filter to calculate the position / velocity 621 based on the acceleration / angular velocity 611, the position 612, the position / velocity 613, the velocity 614, and the position / velocity 615.

[0036] As described above, the aircraft guidance system 10 (aircraft 300) includes a position calculation unit 311 that calculates the aircraft-measured position and velocity (see position / velocity 615), which is the position or velocity of the aircraft, based on the output values ​​(see acceleration / angular velocity 611) of the inertial measurement unit 381 mounted on the aircraft 300. The position calculation unit 311 calculates the aircraft-measured position and velocity (see position / velocity 621) using a predetermined method based on at least one of the ground-measured position and velocity and the satellite-measured position (see position 612), which is the position of the aircraft using satellite positioning, and the output values ​​of the inertial measurement unit 381. The predetermined method is a Kalman filter.

[0037] <<Aircraft: Inertial Measurement Unit Correction Unit>> The inertial measurement unit correction unit 312 calculates the bias drift 631 of the inertial measurement unit 381 based on the position 612 and the position and velocity 613. The bias of the inertial measurement unit 381 is the error in the output (measurement value) of the inertial measurement unit 381, and the drift is the change in the bias over time or the standard deviation.

[0038] For example, when position and velocity 613 can be received from the aircraft management device 200, the inertial measurement unit corrector 312 calculates the acceleration and angular velocity from the changes in the repeatedly acquired position and velocity 613. Next, the inertial measurement unit corrector 312 sets the calculated acceleration and angular velocity as true values, and changes the bias of the inertial measurement unit 381 so that the difference between the sum of the bias and the output value of the inertial measurement unit 381 and the true value approaches zero. The change may be made so that the change value is equal to or less than a predetermined value and the difference approaches zero, or so that the difference is equal to or less than a predetermined ratio, or some other method may be used.

[0039] The inertial measurement unit corrector 312 may calculate the acceleration and angular velocity so as to reduce the difference between the velocity (see position and velocity 615) calculated based on the acceleration and angular velocity 611 and the velocity of the position and velocity 613. The inertial measurement unit corrector 312 may also calculate the acceleration and angular velocity so as to reduce the difference between the position calculated based on the acceleration and angular velocity 611 and the position of the position and velocity 613. The inertial measurement unit corrector 312 may use the position 612 instead of the position of the position and velocity 613.

[0040] As described above, the air vehicle guidance system 10 (air vehicle 300) includes an inertial measurement unit corrector 312 that calculates at least one of the bias and drift (see bias / drift 631 of inertial measurement unit 381) of the inertial measurement unit 381 based on the ground-measured position and velocity (see position / velocity 613) and the air vehicle-measured position and velocity (see position / velocity 615). The inertial measurement unit corrector 312 calculates the bias or drift of the inertial measurement unit 381 based on the satellite-measured position (see position 612), which is the position of the air vehicle using satellite positioning instead of the ground-measured position and velocity, and the air vehicle-measured position and velocity.

[0041] Bias is the error in the output value of the inertial measurement unit 381. Drift is the time change or standard deviation in the error (bias) in the output value of the inertial measurement unit 381.

[0042] <Aircraft: Model Parameter Calculation Unit> The model parameter calculation unit 313 calculates parameters of the aerodynamic model of the aircraft 300 stored in the aircraft information 330. The aerodynamic model is, for example, a model expressed by the following equations (1) to (4).

[0043] x α = (T / m)(sin(θ)cos(ψ)+ cos(θ)sin(φ)sin(ψ)) (1) y α = (T / m)(sin(θ)cos(ψ)+ cos(θ)cos(φ)sin(ψ)) (2) z α =(T / m)(cos(θ)cos(φ)- g) (3) T =C Ｔ ・ρ・A・N (4)

[0044] Here, the meaning of each symbol is as follows: α : Acceleration in the x-axis direction y α : Acceleration in the y-axis direction z α : acceleration in the z-axis direction φ: roll angle θ: pitch angle ψ: yaw angle m: mass of the flying body 300 C Ｔ : Thrust coefficient g: Gravity ρ: Air density (mass density) A: Propeller (blade) area N: Propeller rotation speed (RPM)

[0045] The aerodynamic model is not limited to the formulas (1) to (4), but may be a model that combines aerodynamic coefficients and propeller propulsion models. Also, a model that matches the number of propellers of the flying object 300 may be used.

[0046] The model parameter calculation unit 313 calculates a Strauss coefficient (C ), which is a parameter 632 of the aerodynamic model, so that the speed of the position / speed 613 matches the speed 614 calculated from the acceleration calculated using the aerodynamic model based on the rotational speed of the propeller controlled by the flight control unit 315. Ｔ The model parameter calculation unit 313 may calculate the aerodynamic coefficient and the parameters of the propeller propulsion model so that the speed of the position / speed 613 and the speed 614 match.

[0047] Furthermore, the model parameter calculation unit 313 calculates the Strauss coefficient (C ), which is a parameter 632 of the aerodynamic model, so that the difference between the speed of the position / speed 621 calculated by the position calculation unit 311 and the speed 614 calculated from the acceleration calculated using the aerodynamic model based on the rotational speed of the propeller controlled by the flight control unit 315, becomes small (so that they match). Ｔ ) and aerodynamic coefficients, and parameters of the propeller propulsion model may also be calculated.

[0048] For example, when the position / velocity 613 can be received, the model parameter calculation unit 313 calculates the acceleration of the repeatedly acquired position / velocity 613. Next, the model parameter calculation unit 313 sets this calculated acceleration as a true value, and changes the parameters so that the difference between the acceleration calculated using an aerodynamic model based on the rotational speed of the propeller and the true value approaches 0. The change may be made so that the difference approaches 0 with a change value equal to or less than a predetermined value, or so that the difference becomes equal to or less than a predetermined ratio, or some other method may be used.

[0049] Note that the speeds of the position / speed 613 and the position / speed 621 are speeds affected by wind. The model parameter calculation unit 313 may calculate the parameters of the aerodynamic model when the flying object 300 passes around the weather sensor 530 and the difference between the wind speed measured by the weather sensor 530 and the wind speed around the flying object 300 can be considered small (a predetermined value or less). At this time, the model parameter calculation unit 313 considers the speed obtained by subtracting the wind speed measured by the weather sensor 530 from the speeds of the position / speed 613 and 621 to be the speeds of the position / speed 613 and 621, and calculates the parameters 632 of the aerodynamic model. The model parameter calculation unit 313 may also calculate the parameters of the aerodynamic model when there is no wind (when the wind speed is a predetermined value or less).

[0050] As described above, the aircraft guidance system 10 (aircraft 300) is equipped with a model parameter calculation unit 313 that calculates parameters 632 of the aerodynamic model of the aircraft 300 based on the wind speed measured by the anemometer (see meteorological sensor 530), the propeller rotation speed, and the ground-measured position speed.

[0051] <<Air Vehicle: Environmental Value Calculation Unit>> The environmental value calculation unit 314 calculates the wind speed around the air vehicle 300, which is one of the environmental values. Fig. 5 is a diagram for explaining the processing content of the control unit 310 of the air vehicle 300 according to this embodiment. The environmental value calculation unit 314 and flight control unit 315 will be described below with reference to Fig. 5.

[0052] The environmental value calculation unit 314 calculates a wind speed 661 around the air vehicle 300 based on the speed 651 of the air vehicle 300 calculated from the output of the inertial measurement unit 381, the speed 652 transmitted from the air vehicle management device 200, and a speed 653 (theoretical speed) calculated using an aerodynamic model based on the rotational speed of the propeller of the air vehicle 300 controlled by the flight control unit 315. For example, when the speed 652 is not received, the environmental value calculation unit 314 determines the difference between the speeds 651 and 653 as the wind speed 661. When the speed 652 is received, the environmental value calculation unit 314 determines the difference between the speeds 652 and 653 as the wind speed 661. The environmental value calculation unit 314 may also determine the difference between the position / speed 621 (see FIG. 4 ) and the speed 653 as the wind speed 661.

[0053] As explained above, the thrust device that generates the thrust of the flying body 300 has a propeller. The flying body guidance system 10 (flying body 300) includes an environmental value calculation unit 314 that calculates wind speed 661 around the flying body 300 based on a theoretical speed (see speed 653) calculated based on an aerodynamic model of the flying body 300 and the rotational speed of the propeller that generates the thrust of the flying body 300, and the ground measured position speed (see speed 652).

[0054] <<Air Vehicle: Flight Control Unit>> The flight control unit 315 controls the rotational speed of the propeller of the air vehicle to control the flight speed (including the direction) of the air vehicle 300. Based on the current position of the air vehicle 300 and wind speed 661, the flight control unit 315 calculates a flight speed that will cause the air vehicle 300 to fly along the flight path stored in flight path information 340 (see FIG. 3 ), and controls the rotational speed of the propeller. The flight control unit 315 controls the rotational speed of the propeller by referring to an aerodynamic model.

[0055] As described above, the aircraft guidance system 10 (aircraft 300) is equipped with a flight control unit 315 that controls the propeller rotation speed based on wind speed 661 so that the aircraft 300 flies along the planned flight path.

[0056] <<Air Vehicle: Communication Unit>> The communication unit 316 receives the position and velocity 613 transmitted by the air vehicle management device 200 and outputs it to the position calculation unit 311. The communication unit 316 also periodically transmits the position and velocity 621 of the air vehicle 300 calculated by the position calculation unit 311 to the air vehicle management device 200. The communication unit 316 also periodically transmits the wind speed 661 around the air vehicle 300 calculated by the environmental value calculation unit 314 to the air vehicle management device 200.

[0057] As described above, the flying object 300 is equipped with a communication unit 316 that receives ground-measured position and velocity, which is the position or velocity of the flying object 300 itself (the flying object 300) calculated based on the output of at least one of the cameras 520, 521 and radar 510 installed on the ground.

[0058] <Features of the Aircraft Guidance System> The aircraft guidance system 10 calculates the position and velocity 621 of the aircraft 300 based on the output values ​​(see acceleration and angular velocity 611) of the inertial measurement unit 381 equipped on the aircraft 300, the output values ​​(see position 612) of the GNSS antenna 382, ​​and the position and velocity 613 calculated based on images from the radar 510 and cameras 520 and 521.

[0059] Furthermore, the aircraft guidance system 10 calculates bias drift 631 of the inertial measurement unit 381 based on the position and velocity calculated from acceleration and angular velocity 611 and position and velocity 613. The aircraft guidance system 10 calculates parameters 632 of the aerodynamic model so that the velocity of position and velocity 613 matches velocity 614 calculated from acceleration calculated using an aerodynamic model based on the rotational speed of the propeller.

[0060] The air vehicle guidance system 10 calculates wind speed 661 around the air vehicle 300 based on speed 651 of the air vehicle 300 and speed 653 calculated using an aerodynamic model based on the rotational speed of the propeller. The air vehicle guidance system 10 may calculate wind speed 661 based on speed 652 and speed 653. By using the bias drift 631 of the inertial measurement unit 381, aerodynamic model parameters 632, and wind speed 661 calculated in this manner, the air vehicle guidance system 10 can guide the air vehicle 300 (control the flight of the air vehicle 300) with higher accuracy.

[0061] <<Modification: Calculation of Position and Speed ​​of Aircraft>> The accuracy of the position and speed 613 of the airborne object 300 calculated based on images from the radar 510 and the cameras 520 and 521 decreases as the distance between the airborne object 300 and the radar 510 and the cameras 520 and 521 increases. Furthermore, weather conditions such as rain, clouds, and fog affect the accuracy of the position and speed 613. When the position calculation unit 311 calculates the position and speed 621 using a Kalman filter, the Kalman gain may be adjusted with reference to this accuracy.

[0062] In other words, the flying object control unit 214 transmits the position and velocity 613 to the flying object 300, including the accuracy (reliability) of the position and velocity of the flying object 300 calculated by the flying object detection unit 212. When the accuracy (reliability) is high, the position calculation unit 311 may adjust the Kalman gain so as to assign a greater weight to the position and velocity 613. When calculating the bias drift 631 of the inertial measurement unit 381 and the aerodynamic model parameters 632, the inertial measurement unit correction unit 312 and the model parameter calculation unit 313 may adjust the parameter values ​​used in the calculation depending on the accuracy (reliability).

[0063] <<Variation: Bias / Drift Calculation in Aircraft Management Device>> In the above-described embodiment, the inertial measurement unit correction unit 312, the model parameter calculation unit 313, and the environmental value calculation unit 314 are provided in the aircraft 300. Alternatively, values ​​required to calculate the position / velocity 621, the bias / drift 631 of the inertial measurement unit 381, and the aerodynamic model parameters 632 may be transmitted from the aircraft 300 to the aircraft management device 200 and calculated by the aircraft management device 200. In such an embodiment, the aircraft management device 200 includes the position calculation unit 311 and the inertial measurement unit correction unit 312, and the aircraft control unit 214 receives the output values ​​(measurement values) of the inertial measurement unit 381 transmitted by the aircraft 300.

[0064] As described above, the air vehicle management device 200 includes an air vehicle control unit 214 that receives output values ​​from the inertial measurement unit 381 mounted on the air vehicle 300. The air vehicle management device 200 also includes a position calculation unit 311 that calculates the air vehicle measured position and velocity, which is the position or velocity of the air vehicle 300, based on the received output values ​​from the inertial measurement unit 381. The air vehicle management device 200 also includes an inertial measurement unit correction unit 312 that calculates at least one of the bias and drift of the inertial measurement unit 381 based on the ground measured position and velocity and the air vehicle measured position and velocity.

[0065] <Other Modifications> Although several embodiments of the present invention have been described above, these embodiments are merely illustrative and do not limit the technical scope of the present invention. For example, in the above-described embodiments, an example of a thrust device using propeller rotation by a motor as thrust force was shown, but the thrust device may not be a motor but may be an internal combustion engine (engine). Furthermore, the thrust force is not limited to propeller rotation, and a jet engine may be used as the thrust device.

[0066] The present invention can take on various other embodiments, and various modifications such as omissions and substitutions can be made without departing from the spirit of the present invention. These embodiments and modifications are included in the scope and spirit of the invention described in this specification, etc., and are also included in the invention described in the claims and their equivalents.

[0067] <Hardware Configuration> The air vehicle management device 200 and the air vehicle 300 according to the above-described embodiment are realized by a computer 900 configured as shown in FIG. 6, for example. FIG. 6 is a hardware configuration diagram showing an example of a computer 900 that realizes the functions of the air vehicle management device 200 and the air vehicle 300 according to the above-described embodiment. The computer 900 includes a CPU 901, a ROM 902, a RAM 903, an SSD 904, an input / output interface 905 (referred to as an input / output I / F (Interface) in FIG. 6), a communication interface 906 (referred to as a communication I / F in FIG. 6), and a media interface 907 (referred to as a media I / F in FIG. 6). The computer 900 may include a hard disk drive (HDD) instead of the SSD 904, or may include an HDD in addition to the SSD 904. The computer 900 may also include a flash memory instead of the SSD 904.

[0068] The CPU 901 operates based on programs stored in the ROM 902 or SSD 904, and performs control by the control units 210, 310 (see FIGS. 2 and 3). The ROM 902 stores a boot program executed by the CPU 901 when the computer 900 starts up, programs related to the hardware of the computer 900, and the like. The CPU 901 controls an input device 910 such as a mouse or keyboard, and an output device 911 such as a display or printer, via an input / output interface 905. The CPU 901 acquires data from the input device 910 and outputs generated data to the output device 911 via the input / output interface 905.

[0069] The SSD 904 stores programs executed by the CPU 901 and data used by the programs. The communication interface 906 receives data from other devices (e.g., the aircraft 300 or the aircraft management device 200) (not shown) via a communication network and outputs the data to the CPU 901. It also transmits data generated by the CPU 901 to other devices via the communication network. The media interface 907 reads programs or data stored on a recording medium 912 and outputs the programs to the CPU 901 via the RAM 903. The CPU 901 loads the programs from the recording medium 912 onto the RAM 903 via the media interface 907 and executes the loaded programs. The recording medium 912 may be an optical recording medium such as a DVD (Digital Versatile Disk), a magneto-optical recording medium such as an MO (Magneto Optical Disk), a magnetic recording medium, a conductive memory tape medium, a semiconductor memory, an SD card memory, or the like.

[0070] For example, when the computer 900 functions as the air vehicle management device 200 or the air vehicle 300 according to the above-described embodiments, the CPU 901 of the computer 900 executes the programs 228, 328 (see FIGS. 2 and 3) loaded onto the RAM 903, thereby realizing the functions of the air vehicle management device 200 and the air vehicle 300. The CPU 901 reads and executes the programs from the recording medium 912. Alternatively, the CPU 901 may read the programs from another device via a communication network, or may install and execute the programs 228, 328 from the recording medium 912 onto the SSD 904.

[0071] 10 Aircraft Guidance System 200 Aircraft Management Device 211 Environmental Information Acquisition Unit 212 Aircraft Detection Unit 213 Flight Path Calculation Unit 214 Aircraft Control Unit 230 Aircraft Information Database 240 Flight Information Database 250 Environmental Information Database 300 Aircraft 311 Position Calculation Unit 312 Inertial Measurement Unit Correction Unit 313 Model Parameter Calculation Unit 314 Environmental Value Calculation Unit 315 Flight Control Unit 316 Communication Unit 330 Aircraft Information 340 Flight Path Information 381 Inertial Measurement Unit 510 Radar 520, 521 Camera 530 Weather Sensor (Anemometer)

Claims

1. An aircraft guidance system comprising: an aircraft detection unit that calculates the ground measured position and velocity, which is the position or velocity of the aircraft, based on the output of at least one of a camera and a radar installed on the ground; a position calculation unit that calculates the aircraft measured position and velocity, which is the position or velocity of the aircraft, based on the output value of an inertial measurement unit mounted on the aircraft; and an inertial measurement unit correction unit that calculates at least one of the bias and drift of the inertial measurement unit based on the ground measured position and velocity and the aircraft measured position and velocity.

2. The aircraft guidance system of claim 1, wherein the inertial measurement unit correction unit calculates the bias or drift of the inertial measurement unit based on the satellite-based position, which is the position of the aircraft using satellite positioning instead of the ground-measured position and velocity, and the aircraft-measured position and velocity.

3. The aircraft guidance system of claim 1, wherein the position calculation unit calculates the aircraft measured position and velocity using a predetermined method based on at least one of the ground measured position and velocity and the satellite positioning position, which is the position of the aircraft using satellite positioning, and the output value of the inertial measurement unit.

4. The aircraft guidance system according to claim 3, wherein the predetermined method is a Kalman filter.

5. The aircraft guidance system of claim 1, further comprising an environmental value calculation unit that calculates the wind speed around the aircraft based on a theoretical value speed calculated based on an aerodynamic model of the aircraft and the rotational speed of the propeller that generates the aircraft's thrust, and the ground measured position speed.

6. The aircraft guidance system of claim 5, further comprising a flight control unit that controls the rotational speed of the propeller based on the wind speed so that the aircraft flies along a planned flight path.

7. The aircraft guidance system according to claim 5, further comprising a model parameter calculation unit that calculates parameters of an aerodynamic model of the aircraft based on the wind speed measured by an anemometer, the rotational speed of the propeller, and the ground measurement position speed.

8. The air vehicle guidance system according to claim 1, wherein the bias is an error in the output value of the inertial measurement unit.

9. The air vehicle guidance system according to claim 1, wherein the drift is a time change or standard deviation in an error of an output value of the inertial measurement unit.

10. An aircraft comprising: a communications unit that receives ground-measured position and velocity, which is its own position or velocity calculated based on the output of at least one of a camera and a radar installed on the ground; a position calculation unit that calculates aircraft-measured position and velocity, which is its own position or velocity, based on the output value of an on-board inertial measurement unit; and an inertial measurement unit correction unit that calculates at least one of the bias and drift of the inertial measurement unit based on the ground-measured position and velocity and the aircraft-measured position and velocity.

11. An aircraft management device comprising: an aircraft detection unit that calculates a ground measured position and velocity, which is the position or velocity of the aircraft, based on the output of at least one of a camera and a radar installed on the ground; an aircraft control unit that receives output values ​​of an inertial measurement unit mounted on the aircraft; a position calculation unit that calculates an aircraft measured position and velocity, which is the position or velocity of the aircraft, based on the received output values ​​of the inertial measurement unit; and an inertial measurement unit correction unit that calculates at least one of the bias and drift of the inertial measurement unit based on the ground measured position and velocity and the aircraft measured position and velocity.

12. An aircraft guidance method in which an aircraft guidance system executes the steps of: calculating a ground measured position and velocity, which is the position or velocity of the aircraft, based on the output of at least one of a camera and a radar installed on the ground; calculating an aircraft measured position and velocity, which is the position or velocity of the aircraft, based on the output value of an inertial measurement unit mounted on the aircraft; and calculating at least one of a bias and a drift of the inertial measurement unit based on the ground measured position and velocity and the aircraft measured position and velocity.

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