Aircraft

Abstract

To provide a flying body that can perform highly stable flight.SOLUTION: A flying body 1 includes: a body 10; first rotors 11 installed to the body so as to generate lift force by rotating about an axial center of a first direction; an omnidirectional propulsion unit 2 installed to the body so as to be capable of generating lift force in all directions in a first plane intersecting the first direction and different from the first rotors; and a controller 30 for controlling the omnidirectional propulsion unit.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an aircraft.

Background Art

[0002] There is a multi-rotor type aircraft, also called a drone. This aircraft has a plurality of rotary wings for generating lift. This aircraft may be used for work purposes such as working at high altitudes.

[0003] The fuselage of this aircraft rises by the lift generated in the axial direction as the rotary wings rotate around the axis. Further, this aircraft can move in a specified direction within a plane intersecting the axial direction (for example, within a horizontal plane) by controlling the balance between the inclination of the fuselage and the rotational speed of the rotary wings.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] In some cases, flight stability is required for this aircraft. For example, when used for work purposes, the accuracy of the position for work may be required. However, since this aircraft needs to tilt the fuselage when moving in the horizontal plane, it lacks flight stability. Therefore, it may be difficult to maintain the posture required for work. The present disclosure aims to provide an aircraft capable of highly stable flight.

[0006] An aircraft according to an aspect of the present disclosure includes a main body, a first rotary wing provided on the main body so as to rotate around an axis in a first direction and generate lift, an omnidirectional propulsion unit provided on the main body so as to be capable of generating omnidirectional propulsion force in a first plane intersecting the first direction, the omnidirectional propulsion unit being different from the first rotary wing, and a controller for controlling the omnidirectional propulsion unit.

[0007] Further details will be described as embodiments below.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Modes for Carrying Out the Invention

[0009] <1. Overview of the Aircraft>

[0010] (1) The flying object according to the embodiment includes a main body, a first rotating wing provided on the main body so as to rotate around an axis in the first direction and generate lift, an omnidirectional propulsion unit provided on the main body so as to be able to generate propulsion force in all directions in a first plane intersecting the first direction, and different from the first rotating wing, and a controller for controlling the omnidirectional propulsion unit.

[0011] Since the flying object has an omnidirectional propulsion unit and the controller controls the omnidirectional propulsion unit, it becomes possible to fly while maintaining the attitude of the flying object. As a result, stable flight becomes possible.

[0012] (2) Preferably, the omnidirectional propulsion unit has a second rotating wing different from the first rotating wing that generates propulsion force, and the control of the omnidirectional propulsion unit by the controller includes controlling the output or direction of the second rotating wing so that the direction of the propulsion force is a specified direction in the first plane. Thereby, a propulsion force in a specified direction can be applied to the main body. As a result, the flying object can be moved in a specified direction in the first plane while maintaining its attitude.

[0013] (3) Preferably, the omnidirectional propulsion unit has a plurality of second rotating wings that generate propulsion forces in different directions, and controlling the output includes adjusting the output of each of the plurality of second rotating wings according to the specified direction. Thereby, a propulsion force in a specified direction among the planar directions can be applied to the main body by the balance of the outputs of each of the plurality of second rotating wings.

[0014] (4) Preferably, the second rotating wing is a vertical rotating wing, the omnidirectional propulsion unit has three or more second rotating wings, the second rotating wing is a vertical rotating wing, and the omnidirectional propulsion unit has three or more second rotating wings. This facilitates the calculation of the required output of each of the three or more second rotating wings for applying a propulsion force in a specified direction to the main body.

[0015] (5) Preferably, the second rotor is installed at a position where the outgoing airflow does not overlap with the first rotor or the airflow generated by the first rotor. The fact that the outgoing airflow of the second rotor does not overlap with the first rotor or the airflow generated by the first rotor means that neither the first rotor nor the airflow generated by the first rotor is located ahead in the outgoing direction of the second rotor. As a result, the airflow blown out from the second rotor does not contact either the first rotor or the airflow generated by the first rotor. Therefore, the influence on the lift generated by the first rotor can be suppressed.

[0016] (6) Preferably, the second rotor is installed at a position where the distance from the flight center of gravity is longer than that of the first rotor and the outgoing direction is away from the flight center of gravity. This can prevent the air blown out from the second rotor from hitting the first rotor.

[0017] (7) Preferably, the plurality of second rotors are arranged at equal intervals on a circumference centered on the flight center of gravity in the first plane. This facilitates the calculation of the required output of each of the plurality of second rotors for providing a propulsive force in a specified direction to the main body.

[0018] (8) Preferably, the plurality of second rotors are arranged such that the axial direction of each rotation faces the flight center of gravity. This facilitates the calculation of the required output of each of the plurality of second rotors for providing a propulsive force in a specified direction to the main body.

[0019] (9) Preferably, the plurality of second rotors are arranged such that the distance from each of them to the flight center of gravity is the same. This facilitates the calculation of the required output of each of the plurality of second rotors for providing a propulsive force in a specified direction to the main body.

[0020] (10) Preferably, the controller is configured to receive a designation of a working direction and a designation of a moving direction, and generate a thrust obtained by synthesizing them. Thereby, the flying object can be moved while performing work.

[0021] (11) Preferably, the second rotor is a ducted fan. The ducted fan has a propeller-shaped rotor disposed in a cylindrical duct. Since the ducted fan is covered by the duct, it is resistant to impacts. Therefore, even if the second rotor is disposed on the outer peripheral side of the first rotor, it becomes more resistant to contact. Also, since the ducted fan has a relatively strong output, a small-sized one can be used. As a result, the overall size of the flying object can be reduced.

[0022] (12) Preferably, the flying object further includes an acceleration sensor that detects an acceleration in the direction of the thrust in order to obtain a moving distance in the direction of the thrust. The moving distance is obtained by the integral value of the acceleration from the start of movement. Since the flying object can maintain its attitude and fly by having an omnidirectional propulsion unit, it becomes possible to calculate the moving distance with high accuracy using the detection result of the acceleration sensor.

[0023] <2. Example of Flying Object>

[0024] The flying object 1 according to the present embodiment is a multi-rotor type flying object also called a drone. Specifically, referring to the upper figures of FIGS. 1 and 3, the flying object 1 has a first rotor 11. The first rotor 11 generates lift by rotating around the rotation axis 11A. As shown in FIGS. 1 and 3, the X-axis, Y-axis, and Z-axis are set, the directions of the respective axes are the X direction, Y direction, and Z direction, and the direction of the rotation axis 11A is the Z direction (first direction).

[0025] The first rotor 11 applies a propulsive force L in the Z direction to the aircraft 1 by the lift force generated. The first rotor 11 is provided with respect to the aircraft 1 such that the Z direction is perpendicular, the wind-in side surface faces upward, and the wind-out side surface faces downward. That is, the first rotor 11 is provided with respect to the aircraft 1 such that the wind-out direction W1 is downward. Therefore, the propulsive force L applied is an upward force. The aircraft 1 rises by the propulsive force L. FIG. 1 is a plan view of the aircraft 1, and the upper figure in FIG. 3 is a front view of the aircraft 1.

[0026] The aircraft 1 has a main body 10 and an omnidirectional propulsion unit 2. The main body 10 has a support portion 13. The support portion 13 extends from the main body 10 in a direction away from the center of gravity C1 of the main body 10, and supports the first rotor 11 at its tip. The center of gravity C1 of the main body 10 coincides with the center of gravity of the aircraft 1. That is, it can be said to be the center of gravity C1 of the aircraft 1.

[0027] The main body 10 has a plurality of support portions 13, and each support portion 13 supports the first rotor 11. That is, a plurality of first rotors 11 are supported by the support portions 13 and are provided on the main body 10 via the support portions 13. All of the plurality of first rotors 11 are provided on the main body 10 such that the wind-out direction W1 is downward.

[0028] Preferably, three or more first rotors 11 are provided on the main body 10. As an example, six first rotors 11 are provided on the main body 10. Preferably, the six first rotors 11 are arranged at equal intervals on the circumference of a circle 11B centered on the center of gravity C1 of the main body 10. That is, each support portion 13 extends radially outward in the direction of the diameter of the circle 11B at 60° intervals around the center of gravity C1, and supports the first rotor 11 at its tip.

[0029] By arranging the six first rotors 11 at equal intervals on the circle 11B centered on the center of gravity C1, the lift force generated by each first rotor 11 is evenly applied to the aircraft 1 as the propulsive force L, and the control of the propulsive force L becomes easy.

[0030] The omnidirectional propulsion unit 2 applies omnidirectional propulsion force in the XY plane (the first plane) intersecting the Z direction to the main body 10. Since the first rotor 11 is provided perpendicular to the Z direction with respect to the flying object 1, the XY plane is a horizontal plane.

[0031] The omnidirectional propulsion unit 2 is attached to the main body 10 such that the center of gravity C2 thereof coincides with the center of gravity C1 of the main body 10. That is, the center of gravity C2 of the omnidirectional propulsion unit 2 also coincides with the center of gravity C1 of the flying object 1.

[0032] As shown in FIGS. 2 and 3, the omnidirectional propulsion unit 2 may be retrofitted to the main body 10. Further, the omnidirectional propulsion unit 2 may be detachable from the main body 10. FIG. 2 is a front view of the omnidirectional propulsion unit 2 in a state removed from the main body 10 shown in FIG. 1.

[0033] Referring to FIGS. 2 and 3, the omnidirectional propulsion unit 2 is provided with a mounting portion 16 for mounting to the main body 10. Preferably, the main body 10 has a plurality of legs 19 for landing on the lower surface 10A, and the mounting portion 16 is provided with a through hole 16B for passing the legs 19 therethrough. As an example, the omnidirectional propulsion unit 2 is attached such that the legs 19 of the main body 10 pass through the through hole 16B and the upper surface 16A of the mounting portion 16 is in contact with the lower surface 10A of the main body 10. The attachment method is not limited to a specific method. For example, the upper surface 16A of the mounting portion 16 and the lower surface 10A of the main body 10 may be adhered with an adhesive or connected with bolts.

[0034] The omnidirectional propulsion unit 2 has a second rotor 12 different from the first rotor 11. The second rotor 12 generates a propulsion force by rotating around the rotation axis 12A. The direction of the rotation axis 12A (the second direction) is a direction orthogonal to the Z direction. Since the Z direction is vertical, the direction of the rotation axis 12A is a horizontal direction. In that case, the second rotor 12 is a vertical rotor.

[0035] The second rotor 12 is, for example, a ducted fan. Referring to the enlarged view of the second rotor 12 in FIG. 3, the second rotor 12 which is a ducted fan has a cylindrical duct 121 and a propeller-shaped rotor 122 disposed therein. The axis 122A of the rotor 122 is connected to the second drive unit 18. The second drive unit 18 includes a motor 123. The rotor 122 rotates around the axis 122A following the rotation of the motor 123.

[0036] The second rotor 12 is resistant to impact because the rotor 122 is covered by the duct 121. Therefore, as will be described later, even if the second rotor 12 is disposed at a position farther from the center of gravity of the flying object 1 than the first rotor 11, it becomes stronger against contact. Also, since the ducted fan has a relatively strong output, the second rotor 12 can be miniaturized. As a result, the entire flying object 1 can be miniaturized.

[0037] The omnidirectional propulsion unit 2 has a plurality of second rotors 12 that generate propulsion forces in different directions respectively. Each second rotor 12 is supported by a support portion 14. The support portion 14 has a proximal end 14A joined to the mounting portion 16 and supports the second rotor 12 at the other end 14B.

[0038] The plurality of second rotors 12 are attached to the mounting portion 16 such that their respective rotation axes 12A face the center of gravity C2. Since the center of gravity C2 of the omnidirectional propulsion unit 2 coincides with the center of gravity C1 of the flying object 1, the plurality of second rotors 12 are attached to the main body 10 such that their respective rotation axes 12A face the center of gravity of the flying object 1.

[0039] Preferably, three or more second rotors 12 are arranged in the omnidirectional propulsion unit 2. The three or more second rotors 12 are, for example, three second rotors 12. The three second rotors 12 respectively give propulsion forces F1, F2, F3 that face the center of gravity C1 to the main body 10 by rotating around the rotation axis 12A.

[0040] The three second rotors 12 are arranged at equal intervals on the circumference of a circle 12B centered on the center of gravity C2 of the mounting portion 16. That is, each support portion 14 extends radially outward from the mounting portion 16 in the radial direction of the circle 12B centered on the center of gravity C2 at 120° intervals, and supports the second rotor 12 at its tip. This facilitates the calculation of the required output of each of the three second rotors 12 for applying a propulsive force in a specified direction to the main body 10.

[0041] The second rotor 12 is installed at a position where the outgoing air flow does not overlap with the first rotor 11 or the air flow generated by the first rotor 11. The fact that the outgoing air flow of the second rotor 12 does not overlap with the first rotor 11 or the air flow generated by the first rotor 11 means that neither the first rotor 11 nor the air flow generated by the first rotor 11 is located ahead in the outgoing direction W2 of the second rotor 12. As a result, the air flow blown out from the second rotor 12 does not come into contact with either the first rotor 11 or the air flow generated by the first rotor 11. Therefore, the influence on the lift generated by the first rotor 11 can be suppressed.

[0042] As an example, the second rotor 12 is installed at a position farther from the center of gravity C1 of the flying object 1 than the first rotor 11, and the direction of the outgoing direction W2 is opposite to the direction toward the center of gravity C1 of the flying object 1. Being arranged at a position farther from the center of gravity C1 of the flying object 1 than the first rotor 11 means that the radius of the circle 12B on which the second rotor 12 is arranged is larger than the radius of the circle 11B on which the first rotor 11 is arranged. The radius of the circle 11B is the distance L1 between the first rotor 11 and the center of gravity C1 of the flying object 1. The radius of the circle 12B is the distance L2 between the second rotor 12 and the center of gravity C1 of the flying object 1.

[0043] Preferably, the second rotor 12 is disposed outside the circumscribed circle 11C of the six circles 11D drawn by the tips 111 of the respective first rotors 11 when the six first rotors 11 rotate. Thereby, the air flow blown out from the second rotor 12 does not contact either the first rotor 11 or the air flow blown out by the first rotor 11. Therefore, the influence on the lift generated by the first rotor 11 can be suppressed. Further, the air flow blown out from the first rotor 11 does not contact either the second rotor 21 or the air flow blown out by the second rotor 12. Therefore, the influence on the thrust generated by the second rotor 12 can be suppressed.

[0044] Preferably, the second rotor 12 is provided such that the air flow blown out from the second rotor 12 flows in a direction away from the first rotor 11. As an example, all of the plurality of second rotors 12 are installed with the air outlet direction W2 opposite to the direction toward the center of gravity C1 of the flying object 1. Thereby, the air flow blown out from the second rotor 12 does not contact either the first rotor 11 or the air flow blown out by the first rotor 11. Therefore, the influence on the lift generated by the first rotor 11 can be suppressed.

[0045] For example, the second rotor 12 may be installed between the circle 11B and the circumscribed circle 11C represented by the circle P in FIG. 1 and outside the circle 11D. Thereby, miniaturization of the aircraft can be achieved.

[0046] Note that the second rotor 12 may be composed of a unit including a plurality of rotors having the same direction of the rotation axis. For example, as shown in FIG. 4, the second rotor 12 may be composed of two rotors 124 and 125 in which the direction of the rotation axis 124A and the direction of the rotation axis 125B coincide. The second rotor 12, which is a unit composed of a plurality of rotors 124 and 125, is arranged at equal intervals on the circumference of the circle 12B.

[0047] The flying object 1 realizes movement in an arbitrary direction within the XY plane, that is, horizontal movement, by using the resultant force of the propulsive forces F1, F2, and F3 applied from each of the three second rotors 12. The flying object 1 has a controller 30 that controls the omnidirectional propulsion unit 2. The control of the omnidirectional propulsion unit 2 by the controller 30 includes direction control that sets the direction of the propulsive force of the omnidirectional propulsion unit 2 to a specified direction.

[0048] The control of the omnidirectional propulsion unit 2 includes calculating the propulsive forces F1, F2, and F3 necessary to set the direction of the propulsive force of the omnidirectional propulsion unit 2 to a specified direction, and adjusting the propulsive forces F1, F2, and F3. Adjusting the propulsive forces F1, F2, and F3 includes adjusting the output of each of the plurality of second rotors 12.

[0049] Specifically, as shown in FIGS. 1 to 3, the three second rotors 12 are arranged at equal intervals on the circumference of the circle 12B, so that each of the three second rotors 12 applies propulsive forces F1, F2, and F3 to the main body 10 as shown in FIG. 5. In FIG. 5, it is shown that the propulsive forces F1, F2, and F3 act radially at 120° intervals around the center of gravity C1.

[0050] The propulsive force acting on the center of gravity C1 is obtained by the resultant force of the propulsive forces F1, F2, and F3. For example, the propulsive force T1, whose direction is between the direction of the propulsive force F1 and the direction of the propulsive force F2 and whose magnitude is smaller than the maximum output Fmax of the second rotor 12, is given to the center of gravity C1 and is represented by Equation (1) in FIG. 5. The propulsive force T1 is included in the region S1 in FIG. 5.

[0051] The propulsive force T2, whose direction is between the direction of the propulsive force F1 and the direction of the propulsive force F3 and whose magnitude is smaller than the maximum output Fmax of the second rotor 12, is given to the center of gravity C1 and is represented by Equation (2) in FIG. 5. The propulsive force T2 is included in the region S2 in FIG. 5.

[0052] The thrust force T3 applied to the center of gravity C1, whose direction is between the direction of the thrust force F2 and the direction of the thrust force F3 and whose magnitude is smaller than the maximum output Fmax of the second rotor 12, is represented by Equation (3) in FIG. 5. The thrust force T3 is included in the region S3 in FIG. 5.

[0053] The combinations of the thrust forces F1, F2, and F3 for obtaining the thrust forces T1, T2, and T3 applied to the center of gravity C1 are represented by the coefficient A in Equation (4) when the thrust forces F1, F2, and F3 are represented as A(Fx, Fy) respectively. (Fx, Fy) is the decomposition of the thrust forces F1, F2, and F3 in the X-axis direction and the Y-axis direction respectively.

[0054] That is, from Equation (4), the combinations T1(F1, F2, F3), T2(F1, F2, F3), and T3(F1, F2, F3) of the thrust forces F1, F2, and F3 for obtaining the thrust forces T1, T2, and T3 are obtained as follows. T1(F1, F2, F3)=((kFx,Fy),(kFx,-Fy),(0,0)) T2(F1, F2, F3)=((2kFx,0),(0,0),(-kFx,Fy)) T3(F1, F2, F3)=((0,0),(2kFx,0),(kFx,Fy))

[0055] The controller 30 is a control device composed of a CPU (Central Processing Unit), a memory, etc., which is also called a flight controller. By mounting the omnidirectional propulsion unit 2 on the main body 10, the CPU included in the omnidirectional propulsion unit 2 may be connected to the CPU included in the main body 10 to form the controller 30.

[0056] The flying object 1 has sensors, and sensor signals from the sensors are input to the controller 30. The sensors include, for example, the camera 15A. Also, the sensors may include, for example, the acceleration sensor 15B. Also, the sensors may include, for example, the gyro sensor 15C.

[0057] Further, capture information including captured images from the motion capture device 5, as an example of an external sensor, may be input to the controller 30 as a sensor signal. The motion capture device 5 is, for example, an optical motion capture device. In this case, the capture information includes position information in a capture space composed of a plurality of captured images obtained by a plurality of cameras.

[0058] An operation signal from the operation device 4 that receives a user operation for controlling the aircraft 1 is input to the controller 30. The operation device 4 is assumed to be, for example, a remote controller for remotely controlling the aircraft 1. The operations include operations for instructing the altitude of the aircraft 1, the propulsion direction in the horizontal plane, and the moving speed.

[0059] The controller 30 has a communication unit 31. The communication unit 31 includes a receiver that wirelessly receives an operation signal transmitted from the operation device 4. Further, the communication unit 31 includes a receiver that wirelessly receives data of the captured images transmitted from the motion capture device 5. Further, the communication unit 31 includes an interface connected to the camera 15A and receiving data of the captured images at the camera 15A.

[0060] The controller 30 functions as a state determination unit 32 that determines the state by executing a program stored in the memory by the CPU. Determining the state includes obtaining a value representing the current state of the aircraft 1, and includes, for example, estimating the current position (step S13) and determining the propulsion speed (step S15) shown in FIG. 7.

[0061] Specifically, referring to FIG. 7, the controller 30 receives the input of the capture information from the motion capture device 5 (step S11), and estimates the current position (px, py) of the aircraft 1 as a value representing the state of the aircraft 1 using the capture information (step S13). The current position (px, py) is represented by coordinate values in the xy coordinate system, for example.

[0062] Further, the controller 30 receives an input of a sensor signal from the sensor 15 (step S15), and determines the propulsion speed (vx, vy) of the aircraft 1 as a value representing the state of the aircraft 1 (step S17). The propulsion speed (vx, vy) is represented, as an example, by the velocity component in the x direction and the velocity component in the y direction in a virtual xy coordinate system.

[0063] Determining the state further includes obtaining a value representing the state to be taken by the aircraft 1. Obtaining a value representing the state to be taken includes, as an example, determining the attitude to be taken, as shown in FIG. 7 (step S19). Specifically, the controller 30 receives an input of direction information representing the propulsion direction in the horizontal plane, which is instructed as an operation signal from the operation device 4 (step S19), and determines the attitude to be taken by the aircraft 1 (step S21). The attitude is defined, as an example, by the roll angle θr, the pitch angle θp, and the yaw angle θy. Here, the controller 30 obtains the roll angle θr, the pitch angle θp, and the yaw angle θy to be taken by the aircraft 1.

[0064] The operation device 4 may further include an operation for designating a working direction when using the aircraft 1 for work. The work performed by the aircraft 1 is, for example, work at height. Work at height refers to work involving an operation that physically acts on an object at height. For example, it includes cleaning windows at height, such as in high-rise buildings, pushing an object, pulling an object, etc. Further, work at height refers to work performed while moving at height. For example, spraying pesticides, distributing flyers, and making announcements by voice from height.

[0065] For example, when the work performed by the aircraft 1 is window cleaning, it is assumed that the aircraft 1 is moved so as to move left and right parallel to the window while pressing a cleaning tool against the window. In this case, the operation device 4 designates the direction toward the window, that is, the front, as the working direction, and the left-right direction in the plane parallel to the window as the moving direction.

[0066] The controller 30 functions as a work determination unit 35 that determines the operations associated with work when using the aircraft 1 for work. Determining the operations associated with work is generally the same as determining the state in the state determination unit 32 shown in FIG. 7. When determining the operations associated with work, in the process of obtaining a value representing the state that the aircraft 1 should take, the designation of the operations associated with work is received and that operation is used. For example, in the case of window cleaning, an operation of spraying water on the window while moving along a predetermined trajectory in a plane parallel to the window is assumed. In this case, the operations associated with work include movement along the above trajectory.

[0067] The controller 30 that functions as the work determination unit 35 determines the state of the aircraft 1 and obtains a value representing the state for the operations associated with the designated work. Further, the controller 30 obtains a value representing the state that the aircraft 1 should take for the operations associated with the designated work. The value representing the state that the aircraft 1 should take is obtained using the direction of the thrust applied to the aircraft 1. Obtaining the value representing the state that the aircraft 1 should take includes synthesizing the direction for work and the direction for movement designated by the operation device 4 to obtain the direction of the thrust.

[0068] The controller 30 functions as a first control unit 33 that performs first control. The first control refers to controlling the first drive unit 17 for rotating the first rotor 11. As an example, in the first control, the controller 30 generates a control signal for operating the first drive unit 17 from the value representing the state of the aircraft 1 obtained by determining the state.

[0069] The controller 30 functions as a second control unit 34 that performs second control. The second control refers to controlling the second drive unit 18. As an example, in the first control, the controller 30 generates a control signal for operating the second drive unit 18 using the position (px, py) of the aircraft 1 and the propulsion speed (vx, vy) of the aircraft 1 obtained by determining the state.

[0070] As an example, the controller 30 prestores the rotation amounts of the first rotors 11 and the second rotors 12 according to the thrust applied to the main body 10 by the first rotors 11 and the second rotors 12. The controller 30 calculates the thrust that the first rotors 11 and the second rotors 12 should apply to the main body 10 by using the values representing the state of the flying object 1 and the values representing the state to be taken. At that time, the formulas (1) to (5) in FIG. 4 are used.

[0071] The controller 30 determines the rotation amounts of the first rotors 11 and the second rotors 12 according to the obtained thrust that the first rotors 11 and the second rotors 12 should apply to the main body 10. The controller 30 generates a control signal for rotating the first rotors 11 and the second rotors 12 at the determined rotation amounts.

[0072] The first drive unit 17 and the second drive unit 18 include, for example, motors. In this case, the control signal includes, as an example, a PWM (Pulse Width Modulation) signal. Generating the control signal includes converting the value representing the state of the flying object 1 into a corresponding PWM signal.

[0073] In addition to the normal flight mode, the flying object 1 has a horizontal propulsion mode. The flight mode can be selected by, for example, the operating device 4. An operation signal indicating the selected flight mode is transmitted to the controller 30.

[0074] The normal flight mode refers to a flight mode in which only the first rotors 11 are used and the second rotors 12 are not used. In this case, the controller 30 functions as the first control unit 33 and generates a control signal for operating the first drive unit 17 from the value representing the state of the flying object 1 and the value representing the state to be taken by the flying object 1. For this control, the flight control in a normal multi-rotor type flying object can be used.

[0075] The horizontal propulsion mode refers to a flight mode in which the flying object 1 is flown using the omnidirectional propulsion unit 2. In this case, the controller 30 functions as the first control unit 33 and also functions as the second control unit 34, and generates a control signal for operating the first drive unit 17 and a control signal for operating the second drive unit 18 from the value representing the state of the flying object 1 and the value representing the state to be taken by the flying object 1.

[0076] Note that, as an example, the horizontal propulsion mode may include a position control mode in which the arrival point and speed are preset and the flying object 1 is automatically flown to the arrival point, and a manual mode in which the flying object 1 is flown according to an operation signal from the operation device 4.

[0077] The controller 30 performs the control of the flying object 1 as shown in FIG. 8, for example. That is, referring to FIG. 8, the controller 30 performs movement control (step S100) for flying and moving the flying object 1 to a predetermined destination, and work control (step S200) which is control of flying for work at the destination.

[0078] In the movement control of step S100, the controller 30 switches the control mode of the flying object 1 according to the flight mode, and controls the movement of the flying object 1 in the flow shown in the flowchart of FIG. 9, for example. Specifically, referring to FIG. 9, the controller 30 determines the control mode in the controller 30 based on the flight mode set for the flight of the flying object 1 obtained from the control signal from the operation device 4.

[0079] When the set flight mode is the position control mode ( "position control mode" in step S101), the controller 30 performs the control after step S103. Specifically, the controller 30 performs initial setting for the horizontal propulsion mode (step S103). Setting in step S103 includes setting the roll angle θr and pitch angle θp of the flying object 1 to 0. Thereby, the roll angle θr and pitch angle θp are maintained at 0 also in the subsequent control. Therefore, the horizontal level of the main body 10 of the flying object 1 is maintained.

[0080] Next, the controller 30 receives an input of a destination from the operation signal from the operation device 4 (step S105). Further, the controller 30 determines the propulsion speed from the operation signal from the operation device 4 (step S109). The controller 30 may further receive an operation signal for setting the altitude during movement.

[0081] The controller 30 calculates the direction in which the flying object 1 is to be moved, that is, the yaw angle θy of the flying object 1, from the input destination and the current position (step S107). Note that the current position may be estimated based on the capture information from the motion capture device 5, or may be obtained from the operation signal from the operation device 4.

[0082] The controller 30 calculates the control amount of the second rotor 12 from the yaw angle θy calculated in step S107 and the propulsion speed determined in step S109 (step S111). Further, the controller 30 calculates the control amount of the first rotor 11 necessary to lift to the set altitude (step S111). Specifically, the propulsion force applied to the main body 10 by each of the first rotors 11 and each of the second rotors 12, that is, the rotation amount of each of the first rotors 11 and each of the second rotors 12 is calculated.

[0083] The controller 30 generates control signals for controlling the rotation amounts of the first rotors 11 and the second rotors 12 based on the rotation amounts of the first rotors 11 and the second rotors 12 obtained in step S111, and controls their respective drives (steps S113, S115).

[0084] Specifically, in step S115, the controller 30 calculates the propulsion forces F1, F2, F3 of the second rotors 12 using the equations (1) to (4) of FIG. 4, and generates a control signal so as to rotate each of the second rotors 12 at a rotation amount that results in the calculated propulsion forces F1, F2, F3.

[0085] The controller 30 determines whether the aircraft 1 has arrived at the set destination. When the destination input in step S105 is position information, the controller 30 determines whether the aircraft 1 has arrived at the set destination by comparing the position information obtained from the capture information from the motion capture device 5 with the position information of the destination.

[0086] When the destination input in step S105 is a position specified by the distance and direction from the flight start position, the controller 30 determines whether the aircraft 1 has arrived at the set destination by comparing the moving distance obtained by integrating the acceleration from the start of movement, which is obtained from the sensor signal from the acceleration sensor 15B, with the moving distance input as the destination.

[0087] Note that the process of integrating the acceleration from the start of movement to calculate the moving distance of the aircraft 1 may be performed by an external device of the controller 30, and the calculation result may be given to the controller 30. In any case, since the aircraft 1 has the omnidirectional propulsion unit 2 to fly while maintaining its attitude, it is possible to calculate the moving distance with high accuracy using the detection result of the acceleration sensor.

[0088] The controller 30 maintains the control of each first rotor 11 and each second rotor 12 until the aircraft 1 arrives at the set destination (NO in step S117). Then, when it arrives at the destination (YES in step S117), the controller 30 ends the movement control. As a result, the aircraft 1 will fly to the destination while maintaining its attitude.

[0089] When the set flight mode is the manual mode ( "manual mode" in step S101), the controller 30 performs the control after step S121. Specifically, the controller 30 performs the initial setting for the horizontal propulsion mode (step S121). The setting in step S121 is the same as the setting in step S103. Thereby, even when controlling the movement of the flying object 1 according to the operation signal from the operating device 4, the roll angle θr and the pitch angle θp are maintained at 0. Therefore, the horizontal level of the main body 10 of the flying object 1 is maintained. That is, the flying object 1 can be moved while maintaining the horizontal attitude.

[0090] Next, when the controller 30 receives an operation signal from the operating device 4 (YES in step S123), it executes the processing after step S125. The processing after step S125 is generally the same as the processing after step S107.

[0091] That is, the controller 30 calculates the direction in which the flying object 1 is to be moved based on the control signal, that is, the yaw angle θy of the flying object 1 (step S125). If the operation signal includes a height specification, the controller 30 may further calculate the height. Also, the controller 30 determines the propulsion speed from the operation signal from the operating device 4 (step S127).

[0092] The controller 30 calculates the control amount of the second rotor 12 from the yaw angle θy calculated in step S125 and the propulsion speed determined in step S127 (step S129). Also, the controller 30 calculates the control amount of the first rotor 11 necessary to lift the flying object 1 to the set height (step S129).

[0093] The controller 30 generates control signals for controlling the rotation amounts of the respective first rotors 11 and the respective second rotors 12 based on the rotation amounts of the respective first rotors 11 and the respective second rotors 12 obtained in step S129, and controls the respective drives (steps S131, S133).

[0094] The controller 30 repeats the processes after step S123 until an operation signal instructing the stop of flight is input (NO in step S135). When the stop of flight is instructed (YES in step S135), the controller 30 ends the movement control.

[0095] In addition, when the set flight mode is the normal flight mode ( "normal flight mode" in step S101), the control of the controller 30 is flight control in a normal multi-rotor type aircraft and is not limited to specific control.

[0096] Since the aircraft 1 has the omnidirectional propulsion unit 2 and the controller 30 performs the above control to fly the aircraft 1 in the horizontal propulsion mode, the aircraft 1 will fly while maintaining its attitude. Thereby, the accuracy of controlling the position of the aircraft 1 is improved, and stable flight becomes possible. That is, the accuracy of arriving at the target position can be improved. This leads to an improvement in the accuracy of positioning the operation for work when the aircraft 1 is used for work at the destination.

[0097] When the movement control of the aircraft 1 in step S100 ends, the controller 30 performs the work control in step S200. The work control in step S200 is generally the same as the process flow shown in FIG. 9. In the work control, the controller 30 does not perform the initial settings in steps S103 and S121. Therefore, the attitude of the aircraft 1 can be made as specified according to the work.

[0098] In the work, the controller 30 can receive the designation of the work direction and the movement direction from the operation device 4. When the work is window cleaning, the direction toward the window, that is, the front, is designated as the work direction, and the left - right direction in the plane parallel to the window is designated as the movement direction.

[0099] In this case, the controller 30 obtains the propulsive force applied to the main body 10 of the aircraft 1 by combining the thrust in the working direction and the thrust in the moving direction. Then, the controller 30 performs control to apply the thrust obtained by combining the thrust in the working direction and the thrust in the moving direction to the main body 10 in the same manner as the processing flow shown in FIG. 9.

[0100] When the aircraft 1 has the omnidirectional propulsion unit 2 and the controller 30 controls the second rotor 12 to control the movement in the second direction, when using the aircraft 1 for work, the aircraft 1 can be moved in both the working direction and the moving direction. That is, the positioning accuracy of the aircraft 1 during work can be improved. Therefore, the accuracy of work using the aircraft 1 can be improved.

[0101] <Modification Example>

[0102] As another example, the omnidirectional propulsion unit 2 may have a configuration including one second rotor 12 supported by the support portion 14 at a position coinciding with the center of gravity C2 so that the wind-out direction W2 is variable in the horizontal plane, as shown in FIG. 13. The omnidirectional propulsion unit 2 has a rotation mechanism 14C that rotates the second rotor 12 in the horizontal plane, and the rotation of the rotation mechanism 14C is controlled by the controller 30.

[0103] In this case, the controller 30 controls the rotational amount of the second rotor 12 to control the propulsive force F applied to the main body 10, and controls the rotation angle of the rotation mechanism 14C to control the direction of the propulsive force F applied to the main body 10. Even with such a configuration, the attitude of the aircraft 1 can be stabilized and moved in the second direction in the same manner as described above.

[0104] To evaluate the effect of the omnidirectional propulsion unit 2, the inventors conducted a first verification experiment on the pushing and pulling operation using the aircraft 1. In the first verification experiment, the position control mode was set after the aircraft 1 took off, and the position (px, py), roll angle θr, and pitch angle θp during the pushing and pulling operation using the aircraft 1 were measured. The upper graph in FIG. 10 showing the experimental results indicates the time change of the position (px, py) of the aircraft 1 during flight. The lower graph shows the time change of the roll angle θr and pitch angle θp of the aircraft 1 during flight.

[0105] From FIG. 10, the average error in the position in the x-axis direction was 0.0358 m, and the average error in the position in the y-axis direction was 0.0188 m, both of which were maintained within the range of ±0.05 m. Also, from the lower figure, the attitude of the aircraft 1 during flight was maintained within the range of ±2 degrees. From these experimental results, it was verified that the aircraft 1 can be maintained horizontally during the pushing and pulling operation.

[0106] Furthermore, the inventors conducted a second verification experiment to verify that it is possible to perform highly accurate position control of the aircraft 1 by using the omnidirectional propulsion unit 2. In the second verification experiment, the initial position of the aircraft 1 was set to the position (0, 0), and the position (px, py), roll angle θr, and pitch angle θp were measured at intervals of 0.2 m every 5 seconds. The upper graph in FIG. 11 showing the experimental results indicates the time change of the position (px, py) of the aircraft 1 during flight. The lower graph shows the time change of the roll angle θr and pitch angle θp of the aircraft 1 during flight.

[0107] From FIG. 11, the average error in the position in the x-axis direction was 0.037 m, and the average error in the position in the y-axis direction was 0.0194 m, both of which were maintained within the range of ±0.05 m. Also, during flight, the attitude of the aircraft 1 was maintained within the range of ±2 degrees. From these experimental results, it was verified that the aircraft 1 can control its position with a minimum of 0.2 m.

[0108] The inventors further conducted a third verification experiment to check for deviations in directions other than the moving direction during movement to the destination using the omnidirectional propulsion unit 2. In the third verification experiment, as shown in the left diagram of FIG. 12, the initial position of the aircraft 1 was set as the position (0, 0), and destinations were set radially at intervals of 30° and 0.5 m away from the position (0, 0).

[0109] From the measurement results shown in the right diagram of FIG. 12, it was confirmed that the aircraft 1 moved substantially in a straight line when the target position was on the x-axis or the y-axis, that is, when moving forward and backward or left and right, and there was no deviation in other directions. For destinations set at other positions, it was confirmed that the deviation from the direction towards the destination was about 5°.

[0110] From the above first verification experiment to the third verification experiment, it was verified that by using the omnidirectional propulsion unit 2, the positioning in the flight of the aircraft 1 can be achieved with high precision. Thereby, the flight stability of the aircraft 1 can be improved.

[0111] <3. Addendum> The present invention is not limited to the above-described embodiments, and various modifications are possible.

Explanation of Signs

[0112] 1: Aircraft 2: Omnidirectional propulsion unit 4: Operating device 5: Motion capture device 10: Main body 10A: Lower surface 11: First rotor 11A: Axis of rotation 11B: Circle 11C: Circumscribed circle 11D: Circle 12: Second rotor 12A: Axis of rotation 12B: Circle 13: Support part 14: Support part 14A: Base end 14B: Other end 14C: Rotation mechanism 15: Sensor 15A: Camera 15B: Acceleration sensor 15C: Gyro sensor 16: Mounting part 16A: Upper surface 16B: Through hole 17: First drive unit 18: Second drive unit 19: Leg 21: Second rotor blade 30: Controller 31: Communication unit 32: State determination unit 33: First control unit 34: Second control unit 35: Operation determination unit 111: Tip 121: Duct 122: Rotor blade 122A: Shaft 123: Motor 124: Rotor 124A: Axis of rotation 125: Rotor 125B: Axis of rotation C1: Center of gravity C2: Center of gravity F: Thrust F1: Thrust F2: Thrust F3: Thrust Fmax: Maximum output L: Thrust L1: Distance L2: Distance P: Circle S1: Area S2: Area S3: Area T1: Thrust T2: Thrust T3: Thrust W1: Air outlet direction W2: Air outlet direction θp: Pitch angle θr: Roll angle θy: Yaw angle

Claims

1. a first rotor that rotates about an axis in a first direction to generate lift; a first drive unit that rotates the first rotor; an omnidirectional propulsion unit having three or more second rotors that generate a propulsive force in a direction intersecting the first direction; a second drive unit that rotates the second rotors; a controller that controls the first drive unit and the second drive unit; a main body having the first rotor, the first drive unit, and the controller, to which the omnidirectional propulsion unit is attached; comprising the three or more second rotors of the omnidirectional propulsion unit are each arranged such that the air flow outlet direction of the second rotor faces away from the center of gravity of the main body, and is arranged at a position longer than the distance from the center of gravity of the main body to the first rotor; the controller controls the output of each of the three or more second rotors, so that the omnidirectional propulsion unit can move in any azimuth in a first plane intersecting the first direction from the resultant force of the propulsive forces directed toward the center of gravity given from each of the three or more second rotors; an aircraft.

2. The second rotor is a vertical rotor. The aircraft according to claim 1.

3. The three or more second rotors are arranged at equal intervals on a circumference centered on the center of gravity of the main body in the first plane. The aircraft according to claim 1 or 2.

4. The three or more second rotors are arranged such that the axial direction of each rotation faces the center of gravity of the main body. The aircraft according to any one of claims 1 to 3.

5. Each of the three or more second rotors is arranged such that the distance from the center of gravity of the main body is the same. The aircraft according to any one of claims 1 to 4.

6. The controller is configured to receive a designation of a working direction and a designation of a moving direction, and generate a thrust obtained by synthesizing these. The aircraft according to any one of claims 1 to 5.

7. The second rotor is a ducted fan. The aircraft according to any one of claims 1 to 6.

8. Furthermore, an acceleration sensor for detecting the acceleration in the direction of the propulsive force is provided to obtain the moving distance in the direction of the propulsive force. The aircraft according to any one of claims 1 to 7.

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