JP7779566B2 - Frame assembly for unmanned aerial vehicle and unmanned aerial vehicle equipped with the same - Google Patents

Description

This disclosure relates to a frame assembly for an unmanned aerial vehicle and an unmanned aerial vehicle equipped with the same.

Conventionally, an aircraft constructed of two frames arranged in a first direction and two frames arranged in a second direction that intersect with each other is known (see, for example, Patent Document 1).

China Utility Model Publication No. 204399473

In the aircraft of Patent Document 1, in order to solve the problem of making the aircraft compact, a joint structure that allows the frame to be folded vertically is installed. The installation of such a joint structure is one factor that prevents the aircraft from being lighter, and also poses the problem of higher manufacturing costs.

The present disclosure aims to solve these problems and has as one of its objectives to provide a lightweight, compact, and inexpensively manufactured frame assembly for an unmanned aerial vehicle, as well as an unmanned aerial vehicle equipped with the same.

A frame assembly for an unmanned aerial vehicle according to the present disclosure comprises:
A first pipe;
a second pipe having an inner diameter larger than the outer diameter of the first pipe;
The first pipe is inserted into the second pipe, and the first pipe and the second pipe are fixed to each other.
The unmanned aerial vehicle according to the present disclosure comprises:
a frame assembly for an unmanned aerial vehicle according to the present disclosure;
a main body;
A lift generating unit;
The robot includes a mounting section provided on the main body section and configured to accommodate an object to be mounted.

The present disclosure makes it possible to provide a lightweight, compact, and inexpensively manufactured frame assembly for an unmanned aerial vehicle, as well as an unmanned aerial vehicle equipped with the same.

1 is a plan view of an unmanned aerial vehicle according to one embodiment. FIG. FIG. 2 is a front view of the unmanned aerial vehicle according to the embodiment. FIG. 10 is a perspective view showing a state in which the first pipe is inserted into the second pipe. FIG. 10 is a cross-sectional view showing a state in which the second pipe is rotated relative to the first pipe. FIG. 2 is a side view showing the unmanned aerial vehicle according to the embodiment hovering above the ground. FIG. 2 is a side view showing the flight state of the unmanned aerial vehicle according to the embodiment when hovering. FIG. 2 is a side view showing the flight state of the unmanned aerial vehicle according to the embodiment during horizontal flight. FIG. 1 is an exemplary functional block diagram of an unmanned aerial vehicle.

The contents of one embodiment of the present disclosure will be described below. An unmanned aerial vehicle frame assembly and an unmanned aerial vehicle including the same according to one embodiment of the present disclosure may have the following configuration, for example.
[Item 1]
A first pipe;
a second pipe having an inner diameter larger than the outer diameter of the first pipe and fixed to the first pipe with the first pipe inserted inside.
[Item 2]
Item 1, a frame assembly for an unmanned aerial vehicle,
A frame assembly for an unmanned aerial vehicle, wherein the first pipe and the second pipe are formed using metal or FRP (Fiber Reinforced Plastics), which are metal substrates and/or FRP substrates.
[Item 3]
Item 1 or 2: The unmanned aerial vehicle frame according to item 1,
A frame assembly for an unmanned aerial vehicle, wherein the difference between the outer diameter of the first pipe and the inner diameter of the second pipe is 5 mm or less.
[Item 4]
The unmanned aerial vehicle frame assembly according to any one of items 1 to 3,
A frame assembly for an unmanned aerial vehicle, wherein the insertion amount of the first pipe into the second pipe is 10 mm or more.
[Item 5]
The unmanned aerial vehicle frame assembly according to any one of items 1 to 4,
A frame assembly for an unmanned aerial vehicle, wherein either the first pipe or the second pipe is attached to a main body of the unmanned aerial vehicle.
[Item 6]
The unmanned aerial vehicle frame assembly according to any one of items 1 to 4,
A frame assembly for an unmanned aerial vehicle, wherein either the first pipe or the second pipe is attached to a lift generating portion of the unmanned aerial vehicle.
[Item 7]
The unmanned aerial vehicle frame assembly according to any one of items 1 to 6,
a main body;
An unmanned aerial vehicle comprising: a mounting section provided in the main body section and configured to store an object to be mounted.

<Details of the embodiment>
An unmanned aerial vehicle according to one embodiment of the present disclosure will now be described with reference to the drawings.

<Details of one embodiment of the present disclosure>
FIG. 1 is a plan view of an unmanned aerial vehicle 1 according to one embodiment. FIG. 2 is a front view of the unmanned aerial vehicle 1 according to this embodiment. FIG. 3 is a side view of the unmanned aerial vehicle 1 according to this embodiment. As shown in FIGS. 1 to 3, the unmanned aerial vehicle 1 according to this embodiment is, for example, an unmanned aerial vehicle capable of forward flight or hovering. The unmanned aerial vehicle 1 includes, for example, rotors 2 (lift generating units), a motor 3 for rotating the rotors 2, and a frame 4 that holds the rotors 2 and to which the motor 3 is attached. In this embodiment, the forward-backward direction of the unmanned aerial vehicle 1 is defined as the Y-axis direction, the left-right direction (or horizontal direction) as the X-axis direction, and the up-down direction (or vertical direction) as the Z-axis direction. Here, the +Y direction of the unmanned aerial vehicle 1 is defined as the forward direction. The weight of the unmanned aerial vehicle 1 is not particularly limited, but it is preferable that the weight be, for example, 3 kg or more.

The rotors 2 rotate upon receiving power from the motor 3. The rotation of the rotors 2 generates thrust for the unmanned aerial vehicle 1. The rotors 2 are an example of a lift generating unit. For example, in a multicopter system, each of the multiple rotors 2 is controlled to rotate clockwise or counterclockwise, or to stop. This allows the unmanned aerial vehicle 1 to move vertically and horizontally, as well as turn and rotate along its yaw axis.

The rotor 2 of the present disclosure may have any number of blades (rotors) (e.g., one, two, three, four, or more blades). The blades may have any shape, such as flat, curved, twisted, tapered, or a combination thereof. The blade shape may be fixed or variable, e.g., extendable, foldable, or bendable. The blades may be symmetrical or asymmetrical (having upper and lower surfaces with different shapes). Symmetrical means that the upper and lower surface shapes are symmetrical relative to the chord line of the blade. Asymmetrical means that the blades are not symmetrical. Thus, the blades may be formed into an airfoil, wing, or other geometric shape suitable for generating aerodynamic forces (e.g., lift, thrust) as the blade moves through the air. The blade geometry may be selected to optimize the blade's aerodynamic characteristics, such as increasing lift and thrust and reducing drag. Furthermore, the rotor 2 may be a push type, a pull type, or a combination of these.

The motor 3 causes the rotor 2 to rotate. In other words, the motor 3 is an example of a drive unit. For example, the drive unit for the rotor 2 may be an engine or the like instead of the motor 3. The blades can be driven by the motor 3 and rotate, for example, clockwise and/or counterclockwise around the rotation axis of the motor 3 (e.g., the longitudinal axis of the motor 3). Alternatively, the propeller (rotor 2) that makes up the blades may have a drive shaft to which output is transmitted from the power shaft of the motor 3 via a pulley or the like, and the blades may rotate around the drive shaft.

The rotation of each blade can also be controlled independently. For example, in a multicopter-type unmanned aerial vehicle, some blades rotate in one direction and others in the other. The blades can all rotate at the same rotation speed, or they can each rotate at a different rotation speed. The rotation speed can be determined automatically or manually based on the dimensions of the moving object (e.g., size, weight) or control status (speed, direction of movement, etc.).

The frame 4 is a member that supports the corresponding motors 3 and rotors 2. The frame 4 is an example of a main body. The frame 4 may be provided with color-emitting devices such as LEDs to indicate the rotorcraft's flight status, flight direction, etc. The frame 4 in this embodiment can be formed from a material appropriately selected from metals such as carbon, carbon fiber resin, glass fiber resin, stainless steel, aluminum, aluminum alloy, magnesium, or magnesium alloy, or combinations of these. Note that the configuration disclosed in this embodiment regarding the shape of the frame 4 and the manner in which it is connected to other components is merely an example.

The frame 4 may be, for example, symmetrical, as shown in Figures 1 and 2. As shown in Figures 1 and 2, the frame 4 comprises a first frame 40 and a second frame 41. In the example shown in Figure 1, the second frames 41, 41 are arranged side by side between the first frames 40, 40, which are arranged side by side in approximately parallel relation. The first frame 40 and the second frame 41 are connected by a known method, for example, by joints or caulking.

As shown in FIG. 1, the first frames 40, 40 are aligned at a predetermined interval along the X direction, with the Y direction as the longitudinal direction. Rotating blades 2 are attached to both ends of the first frames 40, 40 via motors 3.

Also, as shown in Figure 1, the second frames 41, 41 are aligned at a predetermined interval along the Y direction, with the X direction being the longitudinal direction.

In this embodiment, the connection points between the two first frames 40, 40 and the two second frames 41, 41 are defined as V1 to V4. A first frame assembly 60 and a second frame assembly 61 are attached to the frame 4. Note that below, the first frame assembly 60 and the second frame assembly 61 may be collectively referred to as the "frame assembly 6." The first frame assembly 60 extends in the X direction from the first frame 40, starting from between vertices V1 and V2 on the first frame 40. The second frame assembly 61 extends in the X direction from the first frame 40 in the opposite direction to the first frame assembly 60, starting from between vertices V3 and V4 on the first frame 40.

1 and 2, a motor mount 31 that supports the rotor 2 and motor 3 is provided at each end of the frame assembly 6. The motor mount 31 is an example of a support portion. The motor mount 31 is provided so that the rotation axis RA of the rotor 2 is inclined toward the front of the unmanned aerial vehicle 1 and relative to the frame 4. For example, the motor mount 31 may have a tapered shape that narrows from the end of the frame 4 toward the longitudinal direction of the frame 4. The motor mount 31 in this embodiment is fixed at the end of the frame 4. In other words, the motor mount 31 fixes the rotor 2 to the frame 4 so that it cannot rotate. In other words, the rotor 2 itself does not rotate relative to the frame 4. Note that while the motor mount 31 in this embodiment is provided so as to be inclined relative to the frame 4, in other embodiments, the motor mount 31 may be provided so that the rotation axis RA of the rotor 2 is perpendicular to the plane defined by the frame 4.

As shown in FIGS. 1 and 2, the first frame assembly 60 includes a first pipe 60A and a second pipe 60B. The first pipe 60A and the second pipe 60B are formed using a metal or FRP substrate, such as a metal substrate such as stainless steel, aluminum, an aluminum alloy, magnesium, or a magnesium alloy, and/or a fiber-reinforced plastic (FRP) substrate. The frame 4 is attached to the end of the first pipe 60A using a known method, such as a joint or crimping. The motor mount 31 is attached to the end of the second pipe 60B. The second pipe 60B has an inner diameter larger than the outer diameter of the first pipe 60A, and is fixed to the first pipe 60A with the first pipe 60A inserted inside. Therefore, although there is actually a step at the boundary between the first pipe 60A and the second pipe 60B, this is not shown in the example shown in FIGS. 1 and 2.

It is preferable that the difference between the outer diameter of the first pipe 60A and the inner diameter of the second pipe 60B be 5 mm or less. This is because a difference of 5 mm or less allows the pipes 60A and 60B to be more firmly and securely fixed to each other. Furthermore, it is preferable that the insertion amount of the first pipe 60A into the second pipe 60B (the overlap length between the first pipe 60A and the second pipe 60B) be 10 mm or more. This is because an insertion amount of 10 mm or more allows the pipes 60A and 60B to be more firmly and securely fixed to each other. Note that "overlap" here refers to the overlap between the end of pipe 60A and the end of pipe 60B when viewed from the radial direction of the pipes 60A and 60B. The overlap length here refers to the distance measured along the axial direction of the pipes 60A and 60B.

As shown in Figure 3, the outer peripheral surface of the first pipe 60A has been subjected to diameter expansion processing. Hereinafter, the portion subjected to diameter expansion processing will be referred to as the "expanded diameter portion." In the example shown in Figure 3, the expanded diameter portion 60C is formed in the middle of the first pipe 60A. The expanded diameter portion 60C has a recess 60D recessed radially inward.

As shown in FIG. 3, a coil spring 60E having an axially elastic force is provided in the space within the second pipe 60B. A protrusion 60F is provided on the inner surface of the second pipe 60B, which passes through the recess 60D a predetermined distance (e.g., 10 mm or more) against the elastic force of the coil spring 60E. The first frame assembly 60 is configured so that, when the second pipe 60B is inserted into the first pipe 60A a predetermined distance (e.g., 10 mm or more), the second pipe 60B can rotate relative to the first pipe 60A (in the direction indicated by the arrow in FIG. 4). As a result of this rotation, as shown in FIG. 4, if the position of the protrusion 60F shifts from the position of the recess 60D, the biasing force of the coil spring 60E presses the protrusion 60F against the enlarged diameter portion 60C. This pressing force positions the second pipe 60B at a predetermined position relative to the first pipe 60A and secures it in place.

Note that, since portions 60A-60F of the first frame assembly 60 and portions 61A-61F of the second frame assembly 61 are similar in order, a description of the configuration of the second frame assembly 61 will be omitted.

The mounting unit 5 is, for example, a mechanism for mounting and holding a load (load object) 51. A battery 50 may be loaded on the mounting unit 5. The mounting unit 5 is provided on the frame 4 and stores the load 51. The batteries 50 are arranged side by side in the X direction with the load 51 sandwiched between them. There is no particular limit to the number of batteries 50 that can be loaded. In a plan view, the mounting unit 5 may have not only a rectangular portion with vertices V1 to V4, but also a rectangular portion that extends beyond this rectangular portion in the -Y direction.

The mounting unit 5 may be fixed to the frame 4 so as not to rotate. Alternatively, the mounting unit 5 may have a mechanism that allows it to rotate relative to the frame 4.

More specifically, as shown in FIG. 5 , the mounting unit 5 has a hinge (connection portion) 52 that connects the housing of the mounting unit 5 to the frame 4. The mounting unit 5 is configured to be rotatable in the pitch direction relative to the frame 4, with the hinge 52 as a fulcrum. Note that there is no particular limit to the angle by which the mounting unit 5 can rotate relative to the frame 4 via the hinge 52.

By providing such a hinge 52, for example, as shown in FIG. 5, the orientation of the mount 5 can be kept horizontal to prevent the cargo 51 from tilting, even when the unmanned aerial vehicle 1 hovers from the ground Gr in a backward tilted attitude. This allows the cargo 51 to be held in a stable state even during flight and delivered to its destination. Note that the hinge 52 in this embodiment rotates the mount 5 only in the forward/backward direction (i.e., the pitch direction), which is the same direction as the direction of travel. However, the hinge 52 may also rotate the mount 5 in the left/right direction (roll direction and/or yaw direction).

Here, the hinge 52 may have a mechanism that actively controls the attitude of the mount 5 using a motor or the like, such as a gimbal. This makes it possible to control the attitude of the mount 5 during flight. This further reduces the wobble (natural vibrations, etc.) of the mount 5, allowing for more stable delivery of the cargo 51. The hinge 52 may also be configured to be connected to the cargo 51 rather than the mount 5. Alternatively, such a hinge 52 may not be provided.

The shape and/or mechanism of the mounting unit 5 is not particularly limited as long as it is capable of storing and holding the luggage 51. Furthermore, the mechanism that maintains the position or tilt of the luggage 51 mounted on the mounting unit 5 may be, for example, a tilt mechanism that tilts and moves the luggage 51. Furthermore, as mentioned above, the mounting unit 5 does not necessarily have to have a structure that allows it to rotate relative to the frame 4.

In order to reduce weight, the unmanned aerial vehicle 1 in this embodiment does not have landing legs. Therefore, in this embodiment, when the unmanned aerial vehicle 1 lands, the mount 5 functions as the landing legs. In other embodiments, landing legs may be provided on the frame 4, mount 5, etc. as appropriate.

Figure 6 is a side view showing the flight state of the unmanned aircraft 1 according to this embodiment when hovering. Figure 7 is a side view showing the flight state of the unmanned aircraft 1 according to this embodiment when flying horizontally. As shown in Figure 6, when the unmanned aircraft 1 is hovering, the unmanned aircraft 1 assumes a backward tilted attitude so that the lift generated by the rotor 2 is directed upward.

On the other hand, as shown in Figure 7, when the unmanned aerial vehicle 1 is flying horizontally, the frame 4 is horizontal, and the rotation axis RA of the rotor 2 faces in the Y-axis direction and diagonally upward. At this time, the lift obtained from the rotor 2 consists of a forward component and an upward component. This allows, for example, the unmanned aerial vehicle 1 to move horizontally in the air while maintaining the attitude of the mount 5 horizontal. Note that the flight mode of the unmanned aerial vehicle 1 according to this embodiment is not limited to the example shown in Figures 5 to 7. For example, when the unmanned aerial vehicle 1 is flying in a hovering position, the unmanned aerial vehicle 1 may be in a horizontal position, and when the unmanned aerial vehicle 1 is flying horizontally, the unmanned aerial vehicle 1 may be in a position tilted forward relative to the cruising direction. Such flight mode can be adjusted as appropriate depending on the configuration of the frame 4, rotor 2, and other components that make up the unmanned aerial vehicle 1.

In order to solve the problem of making the aircraft smaller, some conventional aircraft are equipped with a joint structure that allows the frame to be folded vertically. The installation of such a joint structure is one factor that prevents the aircraft from being lighter, and tends to increase manufacturing costs.

On the other hand, in the unmanned aerial vehicle 1 according to this embodiment, the second pipe 60B (second pipe 61B) can be attached to and detached from the first pipe 60A (first pipe 61A) simply by inserting and removing the second pipe 60B (second pipe 61B) into and from the first pipe 60A (first pipe 61A). Therefore, the configuration according to this embodiment does not require a joint structure that allows the frame to be folded. In other words, the configuration according to this embodiment makes it possible to provide a lightweight, compact frame assembly 6 and an unmanned aerial vehicle 1 equipped with the same that are inexpensive to manufacture.

Furthermore, in this embodiment, even if the second pipe 60B (second pipe 61B) is repeatedly inserted and removed from the first pipe 60A (first pipe 61A), repeatability of the positioning of the second pipe 60B (second pipe 61B) relative to the first pipe 60A (first pipe 61A) is ensured. This ensures that the length of the first frame assembly 60 (second frame assembly 61) remains the same each time. Therefore, the attitude of the unmanned aerial vehicle 1 is always kept symmetrical, and the unmanned aerial vehicle 1 can maintain stable balance during flight.

The unmanned aerial vehicle 1 described above has, for example, the functional blocks shown in Figure 8. Note that the functional blocks in Figure 8 are a minimum reference configuration. Therefore, the functional blocks of the unmanned aerial vehicle 1 according to this embodiment are not limited to this example. The flight controller is a so-called processing unit. The processing unit may have one or more processors, such as a programmable processor (e.g., a central processing unit (CPU)). The processing unit has memory (not shown) and can access the memory. The memory stores logic, code, and/or program instructions that the processing unit can execute to perform one or more steps. The memory may include, for example, a separable medium such as an SD card or random access memory (RAM), or an external storage device. Data acquired from a camera or sensors may be directly transmitted to and stored in the memory. For example, still image and video data captured by a camera or the like is recorded in internal or external memory.

The processing unit includes a control module configured to control the state of the unmanned aerial vehicle 1. For example, the control module controls the propulsion mechanisms (e.g., motors) of the unmanned aerial vehicle 1 to adjust the spatial orientation, velocity, and/or acceleration of the unmanned aerial vehicle 1, which has six degrees of freedom (translational motion _x , _y , and z, and rotational motion θx, θy, and _θz ). The control module can control one or more of the payload 5 and the state of the sensors.

The processing unit can communicate with a transceiver configured to transmit and/or receive data from one or more external devices (e.g., a terminal, a display device, or other remote controller). The transceiver can use any suitable communication means, such as wired or wireless communication. For example, the transceiver can utilize one or more of a local area network (LAN), a wide area network (WAN), infrared, wireless, Wi-Fi, a point-to-point (P2P) network, a telecommunications network, cloud communication, etc. The transceiver can transmit and/or receive one or more of data acquired by sensors, processing results generated by the processing unit, predetermined control data, user commands from a terminal or remote controller, etc.

Sensors in this embodiment may include inertial sensors (acceleration sensors, gyro sensors), GPS sensors, proximity sensors (e.g., lidar), or vision/image sensors (e.g., cameras).

The unmanned aerial vehicle frame assembly of the present disclosure and an unmanned aerial vehicle equipped with the same are expected to be used as an unmanned aerial vehicle for logistics and as an industrial unmanned aerial vehicle in warehouses and factories. The unmanned aerial vehicle of the present disclosure can also be used in aircraft-related industries, such as for multicopters and drones. Furthermore, the present disclosure can also be suitably used as an unmanned aerial vehicle for aerial photography equipped with a camera or other device. This technology can also be used in a variety of industries, including security, agriculture, and infrastructure monitoring.

The above-described embodiments are merely examples intended to facilitate understanding of the present technology and are not intended to limit the scope of the present technology. The present technology can be modified and improved without departing from its spirit, and it goes without saying that equivalents are also included in the present technology.

In the above-described embodiment, the method of fixing the second pipe 60B (second pipe 61B) to the first pipe 60A (first pipe 61A) was described using pressing force from the coil spring 60E (coil spring 61E). However, the fixing method is not limited to this. Fixing methods may also be, for example, press-fitting, screwing, threading, welding, adhesive, caulking by plastic deformation, magnetic adhesion, or other types of fixing methods.

In the above-described embodiment, an example was shown in which the pipes were fixed together by providing a recess 60D (recess 61D) on the first pipe 60A (first pipe 61A) and a protrusion 60F (protrusion 61F) on the second pipe 60B (second pipe 61B). However, the method of fixing the pipes together is not limited to this, and the reverse may also be used.

In the above-described embodiment, an example was shown in which the frame 4 was attached to the end of the first pipe 60A and the motor mount 31 was attached to the end of the second pipe 60B. However, this is not limited to this, and the motor mount 31 may be attached to the end of the first pipe 60A and the frame 4 may be attached to the end of the second pipe 60B.

1 Unmanned Aerial Vehicle 2 Rotor (Lift Generating Unit)
3 Motor 31 Motor mount (support part)
4 Frame (main body)
5 Loading section 51 Baggage (loading object)
52 Hinge (connection part)
6 Frame assembly 60 First frame assembly 61 Second frame assembly 60A, 61A First pipe 60B, 61B Second pipe 60C, 61C Enlarged diameter portion 60D, 61D Recess 60E, 61E Coil spring 60F, 61F Protrusion

Claims (4)

A first pipe;
a second pipe having an inner diameter larger than an outer diameter of the first pipe, and fixed to the first pipe with the first pipe inserted therein;
a first portion having a recess recessed in a radial direction on one side of the first pipe or the second pipe, and having a thickness in the radial direction;
a protrusion on the other side of either the first pipe or the second pipe,
The first pipe is inserted inside, and the protrusion passes through the recess, and then rotates, whereby the first portion and the protrusion are fixed to each other,
the first portion is provided on the first pipe,
A frame assembly for an unmanned aerial vehicle , wherein the protrusion is provided on the second pipe . 2. The unmanned aerial vehicle frame assembly of claim 1,
A frame assembly for an unmanned aerial vehicle, in which the first pipe is inserted inside and the protrusion passes through the recess, and then rotated, thereby pressing the first part and the protrusion against each other and fixing them in place. 3. The unmanned aerial vehicle frame assembly according to claim 1 or 2,
The frame assembly for an unmanned aerial vehicle further comprises a biasing member at an inner end of the second pipe for pressing the first portion and the protrusion against each other. The unmanned aerial vehicle frame assembly according to any one of claims 1 to 3 ;
a main body;
An unmanned aerial vehicle comprising: a mounting section provided in the main body section and configured to store an object to be mounted.