Rotary wing aircraft

Abstract

Rotary wing aircraft maintain the altitude by reducing the rotational speed of rotary wings when the airframes are lifted by an updraft during flight, but when buffeted by a strong updraft, the aircraft may not be able to counter the updraft and may lose control. To solve this problem, the present invention uses a mechanism in which multiple rotary wings are provided in multiple stages, and the thrusts for an airframe in all directions are generated by settting the thrusts from the rotary wings to be directed to multiple angles and combining these thrusts to be controlled. According to the present invention, it is possible to improve the steering stability of rotary wing aircraft not only against updrafts but also against disturbances from various directions such as headwinds, tailwinds, crosswinds, and downdrafts. Furthermore, it is possible to improve stability during movement because the airframe is less inclined during movement of the rotary wing aircraft.

Description

rotorcraft

[0001] The present invention relates to improving the steering stability and flight attitude stability of a rotorcraft.

[0002] For conventional rotorcraft, attempts have been made to improve the handling stability of rotorcraft against disturbances such as updrafts by providing multiple rotors, as described in JP 2019-64581.

[0003] Japanese Patent Application Publication No. 2019-64581

[0004] Rotorcraft using rotors (propellers) with fixed pitch angles adjust the thrust of each rotor by controlling the rotation speed of each rotor. When such rotorcraft are pushed up by an updraft during flight, they maintain their altitude by reducing the rotation speed of the rotors. Therefore, when they are pushed up by a strong updraft, they need to reduce the rotation speed accordingly. However, if the rotor speed is reduced below this minimum, the rotorcraft will not be able to counter the updraft and will become uncontrollable.

[0005] In view of the above problems, an object of the present invention is to improve the steering stability of a rotorcraft against disturbances from various directions, such as not only updrafts but also headwinds, tailwinds, crosswinds, and downdrafts.

[0006] In order to solve the above problems, the rotorcraft of the present invention is characterized by having multiple rotors in multiple stages, such as an upper stage and a lower stage, and by setting the thrust from the rotors to be directed at multiple angles, and by combining and controlling these, it is possible to generate thrust for the aircraft in all directions.

[0007] In explaining the rotorcraft of the present invention, the explanation will be made by comparing a conventional rotorcraft in which four rotors are arranged horizontally with a rotorcraft of the present invention in which multiple rotors are arranged in multiple stages.

[0008] Among the types of rotorcraft, those with four rotors are called quadcopters. This four-rotor design is also commonly used in unmanned aerial vehicles (drones). Here, the names of the rotors of a quadcopter will be referred to as the front right, front left, rear right, and rear left, when viewed from above the aircraft in the direction of travel. Two of the rotors rotate clockwise (right rotation) and two counterclockwise (left rotation), and they are arranged diagonally. The reason for this is to cancel out the rotational reaction force of the rotors. In this explanation, such rotorcraft with four horizontal rotors will be called a flat aircraft.

[0009] Hovering and right and left turns of a plane are generally performed as follows: When a plane hovers, the rotation speed of the four rotors is adjusted to balance the weight of the plane and halt the plane in the air. When a plane turns right, the rotation speed of the two rotors that rotate clockwise (right) is increased and the rotation speed of the two rotors that rotate counterclockwise (left) is decreased to make the right turn. When a plane turns left, the rotation speed of the two rotors that rotate counterclockwise (left) is increased and the rotation speed of the two rotors that rotate clockwise (right) is decreased to make the left turn.

[0010] A plane's movement in each direction is generally as follows: When a plane moves forward, the rotation speed of the rear (rear right, rear left) rotor increases, the plane tilts forward, thrusts backward, and the plane moves forward. When a plane moves backward, the rotation speed of the front (front right, front left) rotor increases, the plane tilts backward, thrusts forward, and the plane moves backward. When a plane moves right, the rotation speed of the left (front left, rear left) rotor increases, the plane tilts right, thrusts left, and the plane moves right. When a plane moves left, the rotation speed of the right (front right, rear right) rotor increases, the plane tilts left, thrusts right, and the plane moves left. When a plane rises, the rotation speed of the four rotors increases, thrusts downward, and the plane rises. When a plane descends, the rotation speed of the four rotors decreases, the downward thrust decreases, and the plane descends under the influence of gravity.

[0011] From the above, in the case of a flat body, the strength of thrust can be adjusted when moving forward, backward, right, left, and ascending, so it is thought that it is possible to adequately counter external disturbances such as strong winds and gusts. However, when descending, the only option is to weaken the thrust, so the range of adjustment to external disturbances is limited, and when a large external force is applied, it is thought that it is unable to counteract that external force and is likely to lose maneuverability.

[0012] The rotorcraft of the present invention has multiple rotors arranged in multiple stages, such as an upper stage and a lower stage. Here, we assume that there are four rotors in the upper stage and four in the lower stage, for a total of eight rotors. Here, a rotorcraft with multiple stages of rotors like this is called a three-dimensional aircraft. Looking from above the aircraft in the direction of travel, the rotors in the upper stage are referred to as the upper stage front right, upper stage front left, upper stage rear right, and upper stage rear left, while the rotors in the lower stage are referred to as the lower stage front right, lower stage front left, lower stage rear right, and lower stage rear left. The rotors in each stage rotate clockwise (right rotation) and counterclockwise (left rotation), and are arranged diagonally. This is to counteract the rotational reaction force of the rotors.

[0013] The three-dimensional aircraft's hovering and right and left turns are performed as follows. When the three-dimensional aircraft halts in the air, the rotation speed of the four lower rotors is adjusted to balance the aircraft's weight and halt the aircraft in the air. When the three-dimensional aircraft turns right, the rotation speed of the four clockwise (right rotating) rotors is increased and the rotation speed of the four counterclockwise (left rotating) rotors is decreased to make the right turn. When the three-dimensional aircraft turns left, the rotation speed of the four counterclockwise (left rotating) rotors is increased and the rotation speed of the four clockwise (right rotating) rotors is decreased to make the left turn.

[0014] The 3D craft moves in each direction as follows: When the craft moves forward, the RPMs of the rotors on the rear (upper rear right, upper rear left, lower rear right, lower rear left) are increased, thrust is directed backward, and the craft moves forward. When the craft moves backward, the RPMs of the rotors on the front (upper front right, upper front left, lower front right, lower front left) are increased, thrust is directed forward, and the craft moves backward. When the craft moves right, the RPMs of the rotors on the left (upper front left, upper rear left, lower front left, lower rear left) are increased, thrust is directed left, and the craft moves right. When the craft moves left, the RPMs of the rotors on the right (upper front right, upper rear right, lower front right, lower rear right) are increased, thrust is directed right, and the craft moves left. When the craft rises, the RPMs of all the rotors on the lower tier are increased, thrust is directed downward, and the craft rises. When a three-dimensional aircraft descends, the rotation speed of the lower rotors is reduced and the rotation speed of all the upper rotors is increased, thrust is directed upward, and the aircraft descends. The action of tilting the aircraft in the direction of travel, which was done when moving a flat aircraft, is no longer necessary.

[0015] From the above, it is believed that in the case of the three-dimensional aircraft of the present invention, it is possible to adjust the strength of thrust when moving forward, backward, right, left, up, and down.

[0016] As described above, the rotorcraft of the present invention is capable of generating thrust in all directions to counteract disturbances from various directions, including not only updrafts but also headwinds, tailwinds, crosswinds, downdrafts, and the like, thereby improving the steering stability of the rotorcraft.

[0017] As described above, with the rotorcraft of the present invention, there is no need to change the attitude of the aircraft when moving forward, backward, right or left, or only a small amount of change is required, which makes it possible to improve the stability of the rotorcraft when moving.

[0018] 1 is a perspective view showing the exterior of a rotorcraft (flat body); FIG. 2 is an explanatory diagram showing how a rotorcraft (flat body) makes a right turn; FIG. 3 is an explanatory diagram showing how a rotorcraft (flat body) makes a left turn; FIG. 4 is an explanatory diagram showing how a rotorcraft (flat body) moves forward, backward, right, left, ascends, and descends; FIG. 5 is a perspective view showing the exterior of a rotorcraft (three-dimensional body) from the front left of the body; FIG. 6 is a perspective view showing the exterior of a rotorcraft (three-dimensional body) from the rear left of the body; FIG. 7 is an explanatory diagram showing how a rotorcraft (three-dimensional body) makes a right turn; FIG. 8 is an explanatory diagram showing how a rotorcraft (three-dimensional body) makes a left turn; FIG. 9 is an explanatory diagram showing how a rotorcraft (three-dimensional body) moves forward, backward, right, left, ascends, and descends.

[0019] Figure 1 is a perspective view showing the exterior of a plane aircraft. Four rotors are arranged horizontally. The rotors generate thrust downward.

[0020] 2 is a plan view showing a right turn of the plane body. When the plane body turns right, the rotation speed of the two rotors 22 and 23 that rotate clockwise (right) is increased, or the rotation speed of the two rotors 21 and 24 that rotate counterclockwise (left) is decreased.

[0021] 3 is a plan view showing the left turn of the plane body. When the plane body turns left, the rotation speed of the two rotors 21 and 24 that rotate counterclockwise (left) is increased, or the rotation speed of the two rotors 22 and 23 that rotate clockwise (right) is decreased.

[0022] 4A is a perspective view showing the plane aircraft stopping in the air. When the plane aircraft stops in the air, the rotation speed of the four rotors 21, 22, 23, and 24 is adjusted to balance the weight of the plane aircraft.

[0023] 4B1 is a perspective view showing the forward tilt of the flat body. When the flat body moves forward, the rotation speed of the rotors on the rear (rear right side 23 and rear left side 24) is increased, causing the body to tilt forward.

[0024] 4B2 is a perspective view showing the forward movement of a flat body. The body is tilted forward to generate thrust backward, causing the body to move forward.

[0025] 4C1 is a perspective view showing the rearward tilt of the flat body. When the flat body moves backward, the rotation speed of the front rotors (front right side 21 and front left side 22) is increased, causing the body to tilt rearward.

[0026] 4C2 is a perspective view showing a plane body moving backward. The plane body is tilted backward to generate thrust forward and move backward.

[0027] 4D1 is a perspective view showing a rightward tilt of the plane body. When the plane body moves to the right, the rotation speed of the rotors on the left side (front left side 22, rear left side 24) is increased, causing the plane body to tilt to the right.

[0028] 4D2 is a perspective view showing the plane body moving to the right. By tilting the body to the right, thrust is generated to the left, causing the plane to move to the right.

[0029] 4E1 is a perspective view showing the left tilt of the flat body. When the flat body moves left, the rotation speed of the rotors on the right side (front right side 21, rear right side 23) is increased, causing the body to tilt left.

[0030] Figure 4E2 is a perspective view showing the leftward movement of the plane body. By tilting the nose to the left, thrust is exerted to the right, causing the plane to move left.

[0031] 4F is a perspective view showing the ascent of a flat body. When the flat body ascends, the rotation speed of the four rotors 21, 22, 23, and 24 is increased to generate thrust downward, causing the flat body to ascend.

[0032] 4G is a perspective view showing the descent of a flat body. When a flat body descends, the rotation speed of the four rotors 21, 22, 23, and 24 is reduced, the downward thrust is weakened, and the plane descends under the influence of gravity. When descending, unlike when moving in other directions, the only way to do so is to weaken the thrust, so the range of control is limited.

[0033] Fig. 5 is a perspective view showing the exterior of the three-dimensional aircraft from the front right. Fig. 6 is a perspective view showing the exterior of the three-dimensional aircraft from the rear right. The thrust generated by the rotors is directed in multiple directions outside the aircraft.

[0034] 7 is a plan view showing the right turn of the three-dimensional aircraft. When the three-dimensional aircraft turns right, the rotation speed of the four rotors 31, 34, 42, and 43 that rotate clockwise (right) is increased, and the rotation speed of the four rotors 32, 33, 41, and 44 that rotate counterclockwise (left) is decreased.

[0035] 8 is a plan view showing the left turn of the three-dimensional aircraft. When the three-dimensional aircraft turns left, the rotation speed of the four rotors 32, 33, 41, and 44 that rotate counterclockwise (left) is increased, and the rotation speed of the four rotors 31, 34, 42, and 43 that rotate clockwise (right) is decreased.

[0036] 9A is a perspective view showing the three-dimensional aircraft stopping in the air. When the three-dimensional aircraft stops in the air, the rotation speed of the four lower rotors 41, 42, 43, and 44 is adjusted to balance the weight of the aircraft.

[0037] 9B is a perspective view showing the forward movement of the three-dimensional vehicle. When the three-dimensional vehicle moves forward, the rotation speed of the rotors at the rear (upper stage rear right side 43, upper stage rear left side 44, lower stage rear right side 33, lower stage rear left side 34) is increased to generate thrust rearward, causing the vehicle to move forward.

[0038] 9C is a perspective view showing the three-dimensional vehicle moving backward. When the three-dimensional vehicle moves backward, the rotation speed of the rotors at the front (upper front right 31, upper front left 32, lower front right 41, lower front left 42) is increased to generate thrust forward, causing the vehicle to move backward.

[0039] 9D is a perspective view showing the three-dimensional aircraft moving to the right. When the three-dimensional aircraft moves to the right, the rotation speed of the rotors on the left side (upper front left side 32, upper rear left side 34, lower front left side 42, lower rear left side 44) is increased, thrust is generated to the left, and the aircraft moves to the right.

[0040] 9E is a perspective view showing the three-dimensional aircraft moving left. When the three-dimensional aircraft moves left, the rotation speed of the rotors on the right side (upper front right side 31, upper rear right side 33, lower front right side 41, lower rear right side 43) is increased, thrust is generated to the right, and the aircraft moves left.

[0041] 9F is a perspective view showing the ascent of the three-dimensional vehicle. When the three-dimensional vehicle ascends, the rotation speed of all of the rotors 41, 42, 43, and 44 in the lower stages is increased to generate thrust downward, and the vehicle ascends.

[0042] 9G is a perspective view showing the descent of the three-dimensional vehicle. When the three-dimensional vehicle descends, the rotation speed of the lower rotors 41, 42, 43, and 44 is reduced, and the rotation speed of all the upper rotors 31, 32, 33, and 34 is increased, so that thrust is exerted upward and the vehicle descends.

[0043] As described above, the rotorcraft of the present invention makes it possible to improve the steering stability of the rotorcraft against disturbances from various directions, including not only updrafts but also headwinds, tailwinds, crosswinds, and downdrafts, making it possible to fly regardless of weather, and it is expected that the range of uses for rotorcraft will be expanded.

[0044] As described above, with the rotorcraft of the present invention, there is no need to change the attitude of the aircraft when moving forward, backward, right or left, or only a small amount of change is required, which makes it possible to improve the stability of the rotorcraft when it is moving, and it is expected that it will be possible to transport materials, personnel, and other items that should be prevented from tipping as much as possible.

[0045] 11 Rotorcraft, flat body 12 Rotorcraft, three-dimensional body 21 Flat body, front right rotor 22 Flat body, front left rotor 23 Flat body, rear right rotor 24 Flat body, rear left rotor 31 Three-dimensional body, lower front right rotor 32 Three-dimensional body, lower front left rotor 33 Three-dimensional body, lower rear right rotor 34 Three-dimensional body, lower rear left rotor 41 Three-dimensional body, upper front right rotor 42 Three-dimensional body, upper front left rotor 43 Three-dimensional body, upper rear right rotor 44 Three-dimensional body, upper rear left rotor 50 Direction of nose 51 Drone control unit (built-in sensor, flight controller, battery, etc.) 52 Main body frame 53 Motor 54 Camera unit 55 Ground contact unit 61 Direction of thrust generated by rotor 62 Direction of aircraft movement 63 Direction of aircraft thrust generation 64 Direction of attitude change 65 Direction of aircraft turning 66 Direction of rotor rotation

Claims

1. A rotary-wing aircraft having a plurality of rotary wings arranged in a plurality of stages, capable of generating thrust in all directions of the aircraft body by directing the thrust generated by the rotary wings in a plurality of directions and combining and controlling the thrust, and thereby enabling the aircraft body to move in all directions.

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