How to mount a drone on a vehicle

Abstract

To provide a technology which can fix a drone onto a vehicle without using a fixture.SOLUTION: A method of fixing a drone 20 onto a vehicle 10 includes a step in which a propeller 26 of the drone 20 landed on the vehicle 10 is rotated to generate a thrust force Fthrust for pressing the drone 20 to the vehicle 10.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for fixing a drone on a vehicle. [Background technology]

[0002] In recent years, the application of unmanned flying objects called drones has progressed. Patent Document 1 discloses a delivery van with a takeoff and landing space for drones on the ceiling. The delivery van carries a drone along with the parcels to deliver them. The drone flies the parcels delivered by the delivery van to the delivery destination and delivers them. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-153337 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technology in Patent Document 1 requires a fixture to secure the drone to the ceiling so that the drone does not fall after landing on the ceiling while the delivery truck is moving.

[0005] An object of the present invention is to provide a technology that can secure a drone to a vehicle without using fasteners. [Means for solving the problem]

[0006] In order to solve the above problem, a method for fixing a drone on a vehicle according to one embodiment of the present invention is a method for fixing a drone on a vehicle, comprising: A step of acquiring a longitudinal acceleration and a lateral acceleration of the vehicle, a step of deriving a longitudinal force and a lateral force of the drone based on the acquired longitudinal acceleration and the lateral acceleration, and a step of deriving a target propeller thrust based on the derived longitudinal force and the lateral force; Rotate the propellers of the drone that has landed on the vehicle, pushing the drone against the vehicle. The target propeller Thrust generation step and, Equipped with. Effect of the Invention

[0007] According to the present invention, a drone can be fixed onto a vehicle without using fasteners. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing a configuration of a vehicle control system according to an embodiment; [Diagram 2] 2 is a front view showing the state in which a drone has landed on the vehicle in the vehicle control system of FIG. 1. [Diagram 3] FIG. 3 is a side view of the vehicle control system of FIG. 2. [Figure 4] FIG. 2 is a diagram showing a functional configuration of the vehicle shown in FIG. [Diagram 5] FIG. 2 is a diagram illustrating the functional configuration of the drone in FIG. 1. [Figure 6] 5 is a flowchart showing an acceleration transmission process in the vehicle of FIG. [Figure 7] 6 is a flowchart showing a process for generating reverse thrust in the drone of FIG. 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] FIG. 1 shows a configuration of a vehicle control system 1 according to an embodiment. The vehicle control system 1 includes a vehicle 10 and a drone 20. In FIG. 1, the size of the drone 20 is greatly exaggerated. The vehicle 10 is, for example, an autonomous vehicle. In the illustrated example, the vehicle 10 is traveling between a vehicle 100a in front and a vehicle 100b behind. The drone 20 is configured to be capable of wireless communication with a predetermined vehicle 10.

[0010] The drone 20 is an autonomous flying vehicle that drives multiple propellers by a motor, and can fly up and down, forward and backward, and left and right by controlling the rotation speed of each propeller. The drone 20 flies above the vehicle 10 by automatic control and monitors the surroundings of the vehicle 10 with the fifth camera 24e. The drone 20 captures an image of an imaging range A5 indicated by a dashed line in FIG. 1 with the fifth camera 24e, and transmits the captured image data to the vehicle 10. The drone 20 can change the position and range to be captured according to instructions transmitted from the vehicle 10. The drone 20 tracks the vehicle 10 as the vehicle 10 moves.

[0011] The vehicle 10 automatically drives based on information about the surroundings of the vehicle 10 detected by an on-board sensor (not shown) and captured image data transmitted from the drone 20. Images captured by the drone 20 may include information about areas that cannot be acquired by the on-board sensor of the vehicle 10, so the vehicle 10 can automatically drive with high accuracy.

[0012] The drone 20 determines whether or not to continue flying during flight, and if it is not possible to continue flying, it lands on the vehicle 10 and provides the vehicle 10 with an image captured from the vehicle 10. In this case, the drone 20 may land on the vehicle 10 while it is moving, or may land when the vehicle 10 stops. For example, the drone 20 determines that it is not possible to continue flying when there is an obstacle that hinders the flight of the drone 20, such as a roadside tree, a pedestrian crossing, or a tunnel, in the direction of travel of the vehicle 10. Details of the conditions for determining that it is not possible to continue flying will be described later.

[0013] Fig. 2 is a front view showing a state in which the drone 20 has landed on the vehicle 10 in the vehicle control system 1 of Fig. 1. Fig. 3 is a side view of the vehicle control system 1 of Fig. 2. In Fig. 2, the vehicle 10 is assumed to be turning. In Fig. 3, the vehicle 10 is assumed to be accelerating.

[0014] When the drone 20 lands on the roof of the vehicle 10, it rotates the flight propellers 26 in the opposite direction to that during flight, generating a thrust Fthrust that pushes the drone 20 against the vehicle 10. The thrust Fthrust is a force that acts in the opposite direction to the lift force, and is hereinafter also referred to as a reverse thrust.

[0015] With an appropriate value of thrust Fthrust, the drone 20 can be fixed on the vehicle 10 without using a fastener. In the example of Fig. 2, lateral acceleration occurs in the vehicle 10, which causes a lateral force Flateral to occur in the drone 20. However, a frictional force corresponding to the thrust Fthrust acts on the contact surface between the legs 28 of the drone 20 and the roof of the vehicle 10, so that the drone 20 is stably fixed to the roof.

[0016] In the example of Figure 3, forward / reverse acceleration is generated in the vehicle 10, which causes a backward forward / reverse force Flong to be generated in the drone 20 as well; however, the drone 20 is stably fixed to the roof due to a frictional force corresponding to the thrust Fthrust.

[0017] This makes it possible to prevent the drone 20 from tipping over or falling from the vehicle 10 due to acceleration, deceleration, or turning of the vehicle 10. Since no mechanical fixing devices are used, increases in weight and cost of the vehicle 10 and drone 20 can also be suppressed.

[0018] The material of the legs 28 of the drone 20 is preferably one that has a large coefficient of friction with the roof of the vehicle 10, and may be, for example, an elastic material.

[0019] The drone 20 includes a first camera 24a, a second camera 24b, a third camera 24c, and a fourth camera 24d. The first camera 24a to the fifth camera 24e are collectively referred to as the cameras 24.

[0020] The first camera 24a is mounted at the tip of a first support 22a that extends approximately horizontally from the main body of the drone 20 to the right of the vehicle 10, and captures images of the imaging range A1 indicated by the dashed line in Figure 2, i.e., the right side of the vehicle 10.

[0021] The second camera 24b is mounted at the tip of the second support 22b, which extends approximately horizontally from the main body of the drone 20 to the left of the vehicle 10, and captures images of the imaging range A2 indicated by the dashed line in Figure 2, i.e., the left side of the vehicle 10.

[0022] The third camera 24c is mounted at the tip of a third support 22c that extends approximately horizontally from the main body of the drone 20 toward the front of the vehicle 10, and captures images of the imaging range A3 indicated by the dashed line in Figure 3, i.e., the area in front of the vehicle 10.

[0023] The fourth camera 24d is mounted at the tip of a fourth support 22d that extends approximately horizontally from the main body of the drone 20 to the rear of the vehicle 10, and captures images of the imaging range A4 indicated by the dashed line in Figure 3, i.e., the area behind the vehicle 10.

[0024] The first camera 24a to the fourth camera 24d mainly capture images of areas that cannot be detected by the on-board sensor of the vehicle 10. The orientation of each of the first camera 24a to the fourth camera 24d may be changeable according to an instruction from the vehicle 10. The drone 20 transmits data of images captured by the first camera 24a to the fourth camera 24d to the vehicle 10. When the drone 20 lands on the vehicle 10, it also transmits information indicating that it has landed to the vehicle 10.

[0025] Even when the drone 20 has landed, the vehicle 10 drives automatically based on surrounding information detected by an on-board sensor and captured image data transmitted from the drone 20. Since the captured image by the drone 20 includes information on the area close to the vehicle 10, the vehicle 10 can drive automatically with high accuracy.

[0026] In this way, even if the drone 20 cannot continue flying, the drone 20 can be landed on the vehicle 10 and images captured from the vehicle 10 can be provided to the vehicle 10, so that the drone 20 can continue to monitor the area around the vehicle 10.

[0027] Fig. 4 shows a functional configuration of the vehicle 10 in Fig. 1. The vehicle 10 includes an on-board sensor 30, an acceleration sensor 31, a navigation device 32, a communication device 34, and a vehicle control device 36.

[0028] The on-vehicle sensor 30 periodically detects information on obstacles such as pedestrians around the vehicle 10 and information on white lines on the road, and outputs the detection results to the vehicle control device 36. The on-vehicle sensor 30 includes at least one of a camera, a LIDAR (Laser Imaging Detection and Ranging), and a radar, for example.

[0029] The acceleration sensor 31 detects the longitudinal acceleration and lateral acceleration of the vehicle 10, and outputs information on the detected acceleration to the vehicle control device .

[0030] The navigation device 32 receives signals from GPS satellites using a GPS receiver (not shown) and derives the position and orientation of the vehicle 10. The position includes latitude and longitude. The navigation device 32 outputs information on the position and orientation of the vehicle 10, and information on the route from the current position to the destination, to the vehicle control device 36.

[0031] The communication device 34 wirelessly communicates with the drone 20. The communication device 34 may communicate with the drone 20 via a network such as the Internet, or may communicate with the drone 20 using a short-range wireless communication technology such as Wi-Fi or Bluetooth (registered trademark). The communication device 34 transmits acceleration information supplied from the vehicle control device 36 to the drone 20. The communication device 34 receives captured image data and the like transmitted from the drone 20 and supplies it to the vehicle control device 36.

[0032] The vehicle control device 36 includes a first acquisition unit 38, a second acquisition unit 40, and a control unit 42. The configuration of the vehicle control device 36 can be realized in hardware by the CPU, memory, and other LSIs of any computer, and in software by a program loaded into memory, but here, functional blocks realized by cooperation between them are depicted. Therefore, it will be understood by those skilled in the art that these functional blocks can be realized in various forms by only hardware, only software, or a combination of both.

[0033] The first acquisition unit 38 acquires information output from the in-vehicle sensor 30 and supplies it to the control unit 42. The second acquisition unit 40 acquires image data captured by the drone 20 output from the communication device 34 and supplies it to the control unit 42.

[0034] The control unit 42 controls a driving device such as a driving motor, a braking device, a steering device, etc. (not shown) according to the information supplied from the first acquisition unit 38 and the second acquisition unit 40, the information on the position and orientation of the vehicle 10 supplied from the navigation device 32, and the route information, to automatically drive the vehicle 10. If there is no obstacle in the traveling direction based on the information on the obstacle around the vehicle 10 detected by at least one of the on-board sensor 30 and the camera 24 of the drone 20, the control unit 42 moves the vehicle 10. For such control, a known automatic driving technology can be used.

[0035] The control unit 42 determines whether imaging from the sky is necessary, and if imaging from the sky is necessary, issues a flight instruction to the drone 20. Specifically, when the drone 20 has landed on the vehicle 10, if the conditions for imaging from the sky are met, the control unit 42 instructs the drone 20 to take off from the vehicle 10 via the communication device 34. In this case, the control unit 42 sets a flight instruction flag to "1" and transmits it to the drone 20.

[0036] Conditions that require imaging from the sky include, for example, when information about the vehicle 10 far away is required, when an area that cannot be detected by the on-board sensor 30 occurs, when the on-board sensor 30 breaks down, or when close-up photography is required. Conditions that require imaging from the sky can also be considered conditions that require taking off and imaging.

[0037] The control unit 42 determines that information about the distant area ahead of the vehicle is necessary, for example, when, due to traffic congestion or the like, most of the area of ​​the acquired image ahead of the vehicle is occupied by the vehicle ahead and the road conditions ahead cannot be fully grasped.

[0038] When part of the information detected by the on-board sensor 30 is affected, for example, by the influence of sunlight such as backlight, or by dirt or water droplets on the surface of the on-board sensor 30, the control unit 42 determines that an area that cannot be detected by the on-board sensor 30 has occurred.

[0039] For example, if the control unit 42 determines based on information acquired by the on-board sensor 30 that the road surface may be rough, that there may be fallen objects, steps, grooves, etc. on the road, or that there may be people, particularly children, elderly people, or disabled people, but the resolution of the on-board sensor 30 makes it impossible to recognize detailed information or the extent of these details, the control unit 42 determines that a close-up shot is necessary.

[0040] When the conditions for capturing images from the sky are met, the control unit 42 also transmits information about the position where the images need to be captured to the drone 20. When the control unit 42 determines that a close-up is required, the control unit 42 also transmits information requesting a close-up to the drone 20.

[0041] When the conditions for capturing images from the sky are not met, the control unit 42 instructs the drone 20 to land on the vehicle 10 via the communication device 34. In this case, the control unit 42 sets the flight instruction flag to "0" and transmits it to the drone 20.

[0042] Fig. 5 shows the functional configuration of the drone 20 in Fig. 1. The drone 20 includes an external sensor 50, an imaging unit 52, a GPS receiving unit 54, a communication device 56, a drone control device 58, and a drive device 60.

[0043] The external sensor 50 includes sensors, such as an acceleration sensor, an angular velocity sensor, a geomagnetic sensor, and an air pressure sensor, that detect information for controlling the attitude of the drone 20. The external sensor 50 supplies the detected information to the drone control device 58.

[0044] The imaging unit 52 includes a plurality of cameras 24, and sequentially supplies time-series images captured periodically to the drone control device 58. The imaging unit 52 may include an ultrasonic sensor, a millimeter wave radar, or the like.

[0045] The GPS receiver unit 54 receives signals from GPS satellites, derives the position and orientation of the drone 20, and supplies it to the drone control device 58. The communication device 56 performs wireless communication with the communication device 34 of the vehicle 10. The communication device 56 receives acceleration information transmitted from the vehicle 10, and supplies it to the drone control device 58.

[0046] The drive unit 60 includes a motor (not shown) and a motor drive circuit (not shown) that respectively drive the multiple propellers 26. Lift is generated by the rotation of the propellers 26. The drive unit 60 can switch between forward and reverse rotation of the propellers 26. The drive unit 60 is controlled by the drone control device 58. Each part of the drone 20, such as the drive unit 60, operates using power supplied from a battery (not shown).

[0047] The drone control device 58 sequentially provides the time-series images captured by the imaging unit 52 to the vehicle 10 via the communication device 56. The drone control device 58 also controls the drive device 60 to control the flight of the drone 20.

[0048] The drone control device 58 has an acquisition unit 62, a derivation unit 64, and a control unit 66. The configuration of the drone control device 58 can be realized in hardware by the CPU, memory, and other LSI of any computer, and in software by a program loaded into the memory, but here, functional blocks realized by the cooperation of these are depicted. Therefore, it is understood by those skilled in the art that these functional blocks can be realized in various forms by only hardware, only software, or a combination thereof.

[0049] The acquisition unit 62 acquires information supplied from the external sensor 50 and image data supplied from the imaging unit 52, and outputs the acquired information to the control unit 66. The acquisition unit 62 supplies the image data supplied from the imaging unit 52 to the communication device 56, and the communication device 56 transmits the image data to the vehicle 10. For example, when the drone 20 is flying, the communication device 56 may transmit image data captured by the fifth camera 24e, and when the drone 20 has landed on the vehicle 10, may transmit image data captured by the first camera 24a to the fourth camera 24d. When the drone 20 is flying, the communication device 56 may also transmit image data captured by the first camera 24a to the fourth camera 24d.

[0050] When the drone control device 58 detects that the drone 20 has landed on the vehicle 10, it starts the control to generate the reverse thrust as follows. In order to detect the landing, for example, a pressure sensor may be provided on the leg 28 of the drone 20.

[0051] The acquisition unit 62 acquires the longitudinal acceleration (along) and lateral acceleration (alateral) of the vehicle 10 output from the communication device 56, and supplies this information to a derivation unit 64.

[0052] The derivation unit 64 derives the longitudinal force Flong and the lateral force Flateral of the drone 20 based on the longitudinal acceleration along and the lateral acceleration alateral of the vehicle 10 according to the following equations (1) and (2). The longitudinal force Flong can also be called the force required to hold the drone 20 on the vehicle 10 against the longitudinal acceleration along. The lateral force Flateral can also be called the force required to hold the drone 20 on the vehicle 10 against the lateral acceleration alateral. In equations (1) and (2), the mass of the drone 20 is Md. Flong=Md·along Equation (1) Flateral = Md alateral Equation (2)

[0053] The derivation unit 64 derives a target propeller thrust Fthrust based on the longitudinal force Flong and lateral force Flateral of the drone 20. The derivation unit 64 derives a resultant force Ftotal of the longitudinal force Flong and lateral force Flateral of the drone 20 according to the following formula (3), and derives a target propeller thrust Fthrust shown in formula (4) based on the resultant force Ftotal. In formula (4), the coefficient of friction between the legs 28 of the drone 20 and the roof of the vehicle 10 is μ. Ftotal=(Flong^2+Flateral^2)^(1 / 2) Equation (3) Fthrust>Ftotal / μ Equation (4)

[0054] The target propeller thrust Fthrust may be, for example, Ftotal / μ multiplied by a predetermined coefficient. The coefficient can be appropriately determined through experiments.

[0055] The control unit 66 reversely rotates the propeller 26 of the drone 20 to generate a target propeller thrust Fthrust. The control unit 66 controls the driving of the motor of the drive unit 60 to rotate the propeller 26 and generate a target propeller thrust Fthrust that presses the drone 20 against the vehicle 10. The control unit 66 rotates the motor in a direction opposite to the rotation direction that generates lift, to generate the target propeller thrust Fthrust.

[0056] While the drone 20 is landing on the vehicle 10, the acquisition unit 62, the derivation unit 64, and the control unit 66 repeat the above-mentioned processing. This controls the target propeller thrust, i.e., the reverse thrust, according to the acceleration of the vehicle 10. For example, when the vehicle 10 is stopped and the longitudinal acceleration and the lateral acceleration are both zero, the target propeller thrust becomes zero and the motor does not rotate.

[0057] When the control unit 66 is instructed to fly by the vehicle 10, that is, when the communication device 56 receives a flight instruction flag set to "1" from the vehicle 10, if the conditions that make flight impossible are not met, the control unit 66 stops the control to generate reverse thrust and controls the drive unit 60 so that the drone 20 takes off from the vehicle 10. Based on the captured image, information for attitude control, and position information, the control unit 66 controls the drive unit 60 so that the drone 20 flies around the vehicle 10, following the vehicle 10 while avoiding collision with obstacles.

[0058] The control unit 66 controls the driving device 60 so that the vehicle flies so as to capture images of positions that require capturing. This allows the vehicle to acquire road conditions far in front of the vehicle when the vehicle-mounted sensor 30 cannot fully grasp road conditions ahead of the vehicle due to congestion, etc. When an area occurs that the vehicle-mounted sensor 30 cannot detect, information on that area can be acquired. When the vehicle-mounted sensor 30 fails, information on the area that should have been captured by the failed sensor can be acquired.

[0059] When the communication device 56 receives information requesting a close-up shot, the control unit 66 controls the driving device 60 to fly to a position where a close-up shot can be taken. This makes it possible to obtain a high-resolution image of an object whose detailed information cannot be recognized due to the resolution of the on-board sensor 30, and therefore to obtain detailed information about the object.

[0060] When the control unit 66 is instructed by the vehicle 10 to fly, the control unit 66 does not allow the drone 20 to take off from the vehicle 10 while the conditions under which flight is not possible are met.

[0061] When conditions that make the drone 20 unable to fly are met during flight of the drone 20, the control unit 66 controls the drive unit 60 to land the drone 20 on the vehicle 10, and provides the vehicle 10 with images captured from above the vehicle 10 by the landed drone 20.

[0062] The conditions under which flight is impossible include, for example, the remaining battery charge being less than a predetermined value, the imaging unit 52 detecting a predetermined flight obstacle, or an unstable flight posture. The predetermined flight obstacle is an obstacle that is difficult for the drone 20 to avoid while tracking the vehicle 10, and examples of such obstacles include a relatively large pedestrian crossing, roadside trees located at a relatively long distance, and tunnels. The control unit 66 can detect the flight obstacle from the captured image using a known image recognition technology.

[0063] The control unit 66 can identify that the flight attitude is unstable based on the information output from the external sensor 50. For example, the flight attitude can become unstable due to a deterioration in weather such as rainfall, snowfall, or strong winds.

[0064] When the control unit 66 lands the drone 20 because a condition that makes the drone 20 unable to fly is met during flight of the drone 20, the control unit 66 controls the drive unit 60 so that the drone 20 takes off again from the vehicle 10 if the condition that makes the drone unable to fly is no longer met and landing has not been instructed by the vehicle 10.

[0065] When the vehicle 10 instructs the drone 20 to land while the drone 20 is flying, that is, when the communication device 56 receives a flight instruction flag set to "0" from the vehicle 10, the control unit 66 controls the drive device 60 to land the drone 20 on the vehicle 10.

[0066] The motor of the drone 20 that has landed on the vehicle 10 may be driven by the power supplied from the vehicle 10, and the battery may be charged. This makes it possible to prevent the remaining battery charge from decreasing due to the generation of reverse thrust. Power may be supplied to the drone 20 by non-contact power supply or by power supply via contacts.

[0067] Next, a description will be given of the overall operation of the vehicle control system 1. Fig. 6 is a flowchart showing the acceleration transmission process in the vehicle 10 of Fig. 4. The acceleration sensor 31 detects the longitudinal acceleration and lateral acceleration of the vehicle 10 (S10), and the vehicle control device 36 transmits the detected longitudinal acceleration and lateral acceleration to the drone 20 (S12), and returns to S10.

[0068] Fig. 7 is a flowchart showing the process of generating reverse thrust in the drone 20 of Fig. 5. This process is started when the drone control device 58 detects landing on the vehicle 10. The communication device 56 receives the longitudinal acceleration and lateral acceleration of the vehicle 10 from the vehicle 10 (S20).

[0069] The derivation unit 64 derives the longitudinal force of the drone 20 from the longitudinal acceleration of the vehicle 10 (S22), and derives the lateral force of the drone 20 from the lateral acceleration of the vehicle 10 (S24). The derivation unit 64 derives a resultant force of the longitudinal force and the lateral force of the drone 20 (S26), and derives a target propeller thrust based on the resultant force (S28). The control unit 66 controls the drive unit 60 to generate the target propeller thrust (S30), and returns to S20.

[0070] According to the embodiment, the rotation of the propeller 26 generates a thrust that presses the drone 20 against the vehicle 10, so the drone 20 can be stably fixed on the vehicle 10 without using a fixing device. This makes it possible to prevent the drone 20 from tipping over or falling off the vehicle 10 due to the acceleration, deceleration, and turning of the vehicle 10. In addition, by generating the minimum necessary reverse thrust in response to the acceleration and deceleration of the vehicle 10, the power consumption of the drone 20 can be reduced.

[0071] The present invention has been described above based on the embodiments. The embodiments are merely examples, and it will be understood by those skilled in the art that various modifications are possible in the combination of each component and each processing step, and that such modifications are also within the scope of the present invention.

[0072] (First Modification) In the embodiment, the motor is rotated in a direction opposite to the rotation direction that generates lift, generating a thrust that pushes the drone 20 against the vehicle 10, but this is not limited thereto. For example, a variable pitch propeller may be adopted as the propeller 26, and the control unit 66 may control the blade angle of the variable pitch propeller so as to generate a thrust that pushes the drone 20 against the vehicle 10. In this modified example, when taking off from a state in which reverse thrust is generated, there is no need to change the rotation direction of the motor, so that it is easier to take off in a shorter time than in the embodiment.

[0073] (Second Modification) In the embodiment, the drone 20 lands on the vehicle 10 when a flight-prohibiting condition is satisfied, but the purpose of the drone 20 landing on the vehicle 10 is not particularly limited. For example, the drone 20 may land on the vehicle 10 to receive a package loaded on the vehicle 10, or may be configured to fly the received package from the vehicle 10 to a delivery destination and deliver it. In addition, when the drone 20 needs to retreat onto a vehicle for some reason, the drone 20 may land on any nearby vehicle by automatic or manual control. In this case, the drone 20 may generate a predetermined constant value of target propeller thrust without acquiring acceleration information from the vehicle on which it has landed.

[0074] (Third Modification) In the embodiment, the drone 20 receives acceleration information of the vehicle 10, but an acceleration sensor provided in the drone 20 may acquire the longitudinal acceleration and lateral acceleration of the drone 20. In this modified example, there is no need to transmit and receive acceleration information between the vehicle 10 and the drone 20, and processing and control can be simplified.

[0075] (Fourth Modification) In the embodiment, if the resultant force of the lateral force and the longitudinal force is zero, the target propeller thrust is also zero, but a lower limit value of the target propeller thrust may be set. In other words, when the derived target propeller thrust is lower than a predetermined lower limit thrust, the derivation unit 64 may set the target propeller thrust to the lower limit thrust. The lower limit thrust may be appropriately set through experiments or simulations. In this modified example, when the acceleration increases from zero, it is only necessary to increase the rotation speed of the motor that is already rotating, and therefore it is easier to increase the reverse thrust in a shorter time than by rotating a stopped motor.

[0076] (Fifth Modification) In the embodiment, a target propeller thrust according to the acceleration is derived, but a predetermined constant value of the target propeller thrust may be used without providing the derivation unit 64. In this case, the target propeller thrust may be calculated in advance based on the maximum value of the resultant acceleration of the lateral acceleration and the longitudinal acceleration that may occur in the vehicle 10, and may be stored in a storage unit (not shown) of the drone control device 58. In this modification, there is no need to transmit and receive acceleration information between the vehicle 10 and the drone 20, and the processing and control can be simplified. In addition, slipping and tipping of the drone 20 can be more reliably suppressed.

[0077] (Sixth Modification) In addition to the processing of the embodiment, the communication device 34 of the vehicle 10 may transmit information on the accelerator operation amount, the brake operation amount, and the steering amount of the vehicle 10 to the drone 20. The communication device 56 of the drone 20 receives information on the accelerator operation amount, etc., and the acquisition unit 62 acquires information on the accelerator operation amount, etc. When at least one of the accelerator operation amount, the brake operation amount, and the steering amount changes, if the target propeller thrust is lower than a predetermined thrust, the control unit 66 generates a predetermined thrust. In this modification, since control to increase the reverse thrust can be started before the acceleration increases, the drone 20 can be more reliably prevented from slipping and falling over.

[0078] (Seventh Modification) In addition to the processing of the embodiment, the vehicle control device 36 may detect that the vehicle 10 may accelerate within a predetermined distance ahead of the vehicle 10 based on map information and the current position, or on the image recognition result of the captured image ahead of the vehicle 10. When an intersection, a red light, a yellow light, a stop line, a railroad crossing, or a curved road exists within a predetermined distance ahead of the vehicle 10, the vehicle control device 36 detects that the vehicle 10 may accelerate within the predetermined distance. The communication device 34 transmits information indicating that the vehicle 10 may accelerate to the drone 20. The communication device 56 of the drone 20 receives the transmitted information, and when the vehicle 10 may accelerate within the predetermined distance, the control unit 66 generates a predetermined thrust if the target propeller thrust is lower than a predetermined thrust. In this modified example, since the control for increasing the reverse thrust can be started before the acceleration increases, the drone 20 can be more reliably prevented from slipping and falling over.

[0079] Any two or more of the first to third modifications may be combined. The modification obtained by combining them may be combined with any one of the fourth to seventh modifications. Any one of the first to third modifications may be combined with any one of the fourth to seventh modifications. [Explanation of symbols]

[0080] 1...vehicle control system, 10...vehicle, 20...drone, 24...camera, 26...propeller, 28...leg, 30...on-board sensor, 31...acceleration sensor, 32...navigation device, 34...communication device, 36...vehicle control device, 38...first acquisition unit, 40...second acquisition unit, 42...control unit, 50...external sensor, 52...imaging unit, 54...GPS receiving unit, 56...communication device, 58...drone control device, 60...drive device, 62...acquisition unit, 64...derivation unit, 66...control unit.

Claims

1. 1. A method for securing a drone on a vehicle, comprising: obtaining longitudinal and lateral acceleration of the vehicle; Deriving longitudinal and lateral forces of the drone based on the acquired longitudinal acceleration and lateral acceleration; Deriving a target propeller thrust based on the derived longitudinal force and lateral force; Rotating a propeller of the drone that has landed on the vehicle to generate the target propeller thrust that pushes the drone against the vehicle; A method for fixing a drone on a vehicle, comprising:

2. The method of fixing a drone on a vehicle as described in claim 1, further comprising a step of setting the target propeller thrust to a predetermined lower limit thrust if the derived target propeller thrust is lower than the predetermined lower limit thrust.

3. A step of acquiring information on an accelerator operation amount, a brake operation amount, and a steering amount of the vehicle; generating a predetermined thrust if the derived target propeller thrust is lower than a predetermined thrust when at least one of the acquired accelerator operation amount, the brake operation amount, and the steering amount has changed; The method for fixing a drone on a vehicle according to claim 1, further comprising:

Images