Unmanned aerial vehicles

Abstract

The present invention provides an unmanned aerial vehicle that can stably contact the ceiling without bouncing back, even when performing tasks that involve contact with the ceiling. [Solution] The device comprises a main body 20 equipped with a lift-generating means, a contact device (contact portion 383) located above the main body and in contact with the ceiling, a link mechanism connected to the contact device and enabling the contact device to be displaced along a predetermined trajectory relative to the main body, and an elastic body connecting the main body and the link mechanism and biasing the contact device to a predetermined position relative to the main body via the link mechanism. When the contact device comes into contact with the ceiling, the contact device, which is displaced as a result of the contact, is subjected to a reaction force from the ceiling and a restoring force from the elastic body acting in the opposite direction to the reaction force.

Description

Technical Field

[0001] This invention relates to unmanned aircraft, such as multicopters and the like.

Background Art

[0002] In recent years, attempts have been made to use unmanned aircraft, such as multicopters, for various operations. For example, there is a known example of using a multicopter for wall surface work (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Among the operations expected to be realized by unmanned aircraft, there is an operation performed on the ceiling. In this type of operation, it may be necessary to bring a part of the unmanned aircraft into contact with or press against the ceiling.

[0005] However, when an unmanned aircraft attempts to perform an operation involving contact with the ceiling, there is a risk that the aircraft body will bounce back from the ceiling due to the reaction force from the ceiling, compromising flight stability.

[0006] This invention has been made in view of the above - described technical background, and its object is to provide an unmanned aircraft that can stably contact the ceiling without bouncing back from the ceiling even when performing an operation involving contact with the ceiling.

Means for Solving the Problems

[0007] The above - described technical problems can be solved by an unmanned aircraft having the following configuration and the like.

[0008] In other words, the unmanned aerial vehicle according to this embodiment comprises a main body equipped with a lift generating means, a contact device located above the main body and in contact with the ceiling, a link mechanism connected to the contact device and enabling the contact device to be displaced along a predetermined trajectory relative to the main body, and an elastic body connecting the main body and the link mechanism and biasing the contact device to a predetermined position relative to the main body via the link mechanism, wherein when the contact device comes into contact with the ceiling, the contact device that is displaced as a result of the contact is subjected to a reaction force from the ceiling and a restoring force from the elastic body acting in the opposite direction to the reaction force.

[0009] With this configuration, the contact device that comes into contact with the ceiling is subjected to both a reaction force from the ceiling and a restoring force from the elastic body acting in the opposite direction to the reaction force, thereby absorbing the impact caused by contact with the ceiling. As a result, it is possible to provide an unmanned aerial vehicle that can make stable contact with the ceiling without bouncing back, even when performing tasks that involve contact with the ceiling. Furthermore, by providing a link mechanism between the elastic body and the contact device, stable displacement of the contact device can be achieved.

[0010] Here, the term "ceiling" includes not only the ceiling itself but also objects installed on the ceiling. Furthermore, "ceiling" includes not only indoor ceilings but also ceilings of structures that are open to the outdoors. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an unmanned aerial vehicle that can stably contact the ceiling without bouncing back, even when performing tasks that involve contact with the ceiling. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a block diagram of a multicopter. [Figure 2] Figure 2 is a block diagram showing the details of the flight control unit (flight controller). [Figure 3]Figure 3 is an external view showing the overall configuration of the multicopter. [Figure 4] Figure 4 is an explanatory diagram illustrating the process by which a multicopter makes contact with the ceiling. [Modes for carrying out the invention]

[0013] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

[0014] (1. First Embodiment) As a first embodiment, an example of applying the present invention to an unmanned aerial vehicle equipped with a work tool, particularly a multirotor, will be described.

[0015] In this embodiment, a multirotor is used, but the present invention may also be applied to other unmanned aerial vehicles. Unmanned aerial vehicles may also be called UAVs (Unmanned Aerial Vehicles), and include, for example, drones. Furthermore, unmanned aerial vehicles may also include model aircraft with an airframe weight of less than 100g.

[0016] (1.1 Multicopter Configuration) Figure 1 is a block diagram of the multicopter 100 according to this embodiment. In this embodiment, the multicopter 100 is, for example, a quadcopter having four rotors.

[0017] As is clear from the figure, the multicopter 100 is equipped with a flight control unit 11, a power supply unit 12, a receiver 13, a sensor group 17, four motors 16 (16a to 16d), and four drive circuits 15 (15a to 15d).

[0018] In this embodiment, the flight control unit 11 is a so-called flight controller (FC) and performs overall control of the multirotor. Details of the flight control unit 11 will be described later.

[0019] In this embodiment, the power supply unit 12 is a DC battery and supplies power or electrical energy to each part of the multicopter 100. The receiver 13 receives signals such as operation signals from a remote controller (not shown) and provides them to the flight control unit 11. The sensor group 17 is sensors other than the sensors included in the IMU described later, and in this embodiment, includes sensors such as a GPS sensor, an air pressure sensor, and a ToF sensor.

[0020] The flight control unit 11 is connected to each motor 16 via each drive circuit 15 and controls each motor 16. Further, the flight control unit 11 is also connected to at least the receiver 13 and the sensor group 17, and processes commands from the receiver 13 and information from the sensor group 17. The power supply unit 12 provides a pair of power lines with different polarities and supplies power to at least the flight control unit 11, the receiver 13, the sensor group 17, and each drive circuit 15 (15a to 15d).

[0021] FIG. 2 is a block diagram showing details of the flight control unit 11 (flight controller). As is clear from the figure, the flight control unit 11 includes a microprocessor unit (MCU) 111, a DC / DC converter 112, and an inertial measurement unit (IMU) 113 inside. In the example of the figure, power is supplied to the microprocessor unit 111 and the inertial measurement unit 113 via the DC / DC converter 112 by a pair of power lines from the power supply unit 12.

[0022] The microprocessor unit 111 further includes, inside, a processor such as a CPU that executes programs, etc., a memory or storage medium such as ROM / RAM that stores programs and data (including a non-transitory computer-readable storage medium), input / output ports such as GPIO (General Purpose Input / Output), and other peripheral functions such as timers. The microprocessor unit 111 performs flight control of the multicopter 100 based on the outputs of the inertial measurement unit 113 and other sensors, etc.

[0023] The DC / DC converter 112 is a device that converts the voltage related to the power supplied from the power supply unit 12 into the operating voltage of each device.

[0024] The inertial measurement unit 113 is a device that detects the three-dimensional inertial motion acting on the multicopter 100, and in this embodiment, it includes a 6-axis sensor, i.e., a 3-axis acceleration sensor and a 3-axis angular velocity sensor (or a 3-axis gyroscope). However, the configuration of the inertial measurement unit 113 is not limited to this example, and it may also be made into a 9-axis sensor by adding a 3-axis geomagnetic sensor, or it may be equipped with other sensors such as a temperature sensor for temperature compensation.

[0025] Figure 3 is an external view showing the overall configuration of the multicopter 100. In this figure, the multicopter 100 is grounded and in a natural state. As is clear from this figure, the multicopter 100 has a main body 20 with legs, and a spring 32, linkage mechanisms (35, 36, 37), and work tools 38 are connected to the top surface of the main body 20.

[0026] In this embodiment, the work device 38 is a heating tester for testing fire alarms. By flying the multicopter 100 and covering the fire alarm installed on the ceiling with a substantially hollow cylindrical contact portion 383, the fire alarm can be inspected.

[0027] However, the work tools 38 are not limited to these examples. Therefore, various other types of work tools used for work on ceilings or ceiling fixtures can be employed. For example, a tool used for painting ceilings may be used as the work tool 38.

[0028] In addition to the above-described configuration (see Figures 1 and 2), the main body 20 is provided with at least four lift-generating means, each driven by one of four motors 16. In this embodiment, the lift-generating means is a rotor blade (not shown) whose rotational axis is oriented vertically.

[0029] Furthermore, the means of generating lift are not limited to these examples, and other means of generating lift can be employed.

[0030] A flat surface is provided on the top surface of the main body 20, and a base member 31 is fixed to this surface. Near the center of the base member 31, one end of a spring 32, which serves as an elastic means, is rotatably supported via a bearing.

[0031] With this configuration, the extension of the spring 32 provides a restoring force, and as will be described later, it is possible to provide an appropriate force according to the displacement of the work tool 38.

[0032] In this embodiment, a spring 32 is used as the elastic means, but the system is not limited to this configuration. Therefore, other configurations with similar functions, namely those that provide a restoring force through displacement, can be employed, and for example, means such as elastomers may be used.

[0033] In this embodiment, the spring 32 is fixed to the end of the first link 36 at an acute angle with respect to the top surface of the main body 20.

[0034] With this configuration, the height caused by the elastic body can be reduced compared to the case where the elastic body is placed perpendicular to the top surface of the main body 20 and the work tool 38 is placed in front of it. This suppresses fluctuations in the center of gravity and reduces the risk of impairing the flight stability of the multicopter 100.

[0035] A roughly figure-eight shaped link support member 35 is fixed to the end of the base member 31, supporting the first link 36 and the second link 37, which will be described later.

[0036] Near the center of the link support member 35, a first link 36, which is either "V" shaped or an obtuse L-shaped, is rotatably supported via a bearing around its bent portion. Furthermore, near the upper end of the link support member 35, one end of a rod-shaped second link 37 is rotatably supported via a bearing.

[0037] At the radially outer ends of the first link 36 and the second link 37, as viewed from the center of the main body 20, a fixing device 381, which forms part of the work tool 38, is rotatably fixed via bearings. In this case, the longitudinal axis of the fixing device 381 is parallel to the vertical direction. That is, the first link 36 and the second link 37 constitute a parallel link, and in response to external forces, they linearly guide the fixing device 381 in the vertical direction.

[0038] With this configuration, the parallel link mechanism (35, 36, 37) can be used to achieve stable displacement of the work tool 38.

[0039] The other end of the spring 32 (the end opposite to the side supported by the base member 31) is supported at the end of the first link 36 closer to the center of the main body 20, via a bearing, in a manner that allows it to rotate.

[0040] In summary, one end of the spring 32 is rotatably supported by the base member 31, and the other end is rotatably supported by the end of the first link 36. Also, one end of the first link 36 is rotatably supported by the end of the spring 32, the bent portion in the middle is rotatably supported by the link support member 35, and the other end is rotatably supported by the fastener 381. Furthermore, one end of the second link 37 is rotatably supported by the link support member 35, and the other end is rotatably supported by the fastener 381.

[0041] A support rod 382, ​​which forms part of the work tool 38, is attached horizontally to the tip of the fixing device 381, and a hollow cylindrical contact portion 383, which forms part of the work tool 38 and can come into contact with the ceiling, is attached near the tip of the support rod 382.

[0042] In other words, in the example shown in the figure, the work tool 38 is biased by a spring 32 acting as a biasing means via a link mechanism (35, 36, 37). The spring constant and natural length of the spring 32 are determined so that when the weight of the work tool 38 and the restoring force of the spring 32 are balanced, the work tool 38 remains in an appropriate position so that it does not come into contact with the main body 20, etc.

[0043] With this configuration, the work tool 38 can be biased against the main body 20 with an appropriate biasing force. This allows it to exhibit shock absorption even with slight changes in load.

[0044] (1.2 Contact of multicopters with the ceiling) Next, we will describe the process by which the multicopter 100, equipped with the above configuration, comes into contact with the ceiling.

[0045] Figure 4 is an explanatory diagram illustrating the process by which the multicopter 100 comes into contact with the ceiling. Figure (A) shows the state immediately after the contact portion 383 (not shown in the figure) comes into contact with the ceiling, and Figure (B) shows the state after the contact portion 383 (not shown in the figure) has come into contact with the ceiling, in other words, the state in which the contact portion 383 is pressed against the ceiling.

[0046] As is clear from Figure (A), when the multicopter 100 approaches the ceiling, either by operation from a remote controller or autonomously, the contact portion 383 (not shown) first makes contact with the ceiling. Due to this contact, a reaction force acts on the work tool 38 from the ceiling, and the work tool 38 (or fixing device 381) is displaced vertically downward relative to the main body 20 along the guide provided by the parallel link mechanism (35, 36, 37).

[0047] On the other hand, as is clear from Figure (B), when the multicopter 100 approaches the ceiling sufficiently, the work tool 38 is displaced further vertically downward relative to the main body 20. Due to this downward displacement, the first link 36 is rotated clockwise in the figure around the bent portion in the middle, and as a result, the spring 32 is stretched. Now, when the spring 32 that was biasing the work tool 38 stretches, a restoring force acts on the spring 32 in proportion to the amount of displacement. Therefore, a force acts on the first link 36 that tries to rotate it counterclockwise. As a result, a force acts on the work tool 38 via the parallel links (36, 37) in the opposite direction to the reaction force from the ceiling, that is, a force that tries to push it back vertically upward.

[0048] With this configuration, the work tool 38 that comes into contact with the ceiling is subjected to both a reaction force from the ceiling and a restoring force from an elastic body acting in the opposite direction to the reaction force, thereby absorbing the impact caused by contact with the ceiling. As a result, even when performing work that involves contact with the ceiling, it is possible to provide a multicopter 100 that can make stable contact with the ceiling without bouncing back.

[0049] Furthermore, by interposing a link mechanism between the elastic body and the work tool 38, stable displacement of the work tool 38 can be achieved.

[0050] (2. Variant) The present invention can be implemented in various modified forms.

[0051] In the embodiments described above, the work tool 38 was described as being displaced in a linear trajectory (vertically) by parallel links, but the present invention is not limited to this configuration. Therefore, it may be displaced linearly in directions other than the vertical direction. It may also be displaced in a non-linear trajectory.

[0052] Although embodiments of the present invention have been described above, these embodiments only represent a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments. Furthermore, the above embodiments can be combined as appropriate without creating any contradictions. [Industrial applicability]

[0053] This invention can be used in industries that manufacture unmanned aerial vehicles and the like. [Explanation of Symbols]

[0054] 11 Flight Control Unit 111 Microprocessor Unit (MPU) 112 DC / DC Converters 113 Inertial Measurement Unit (IMU) 12 Power supply section 15 Drive Circuit 16 motors 17 sensor groups 20 Main body 31 Base member 32 springs 35 Link support member 36. Link 1 37. Second Link 38 Work Tools 381 Fixtures 382 Support rod 383 Contact area 100 multicopters

Claims

1. A main body equipped with a means for generating lift, A contact device is located above the main body and in contact with the ceiling, A link mechanism connected to the aforementioned contact device, which allows the contact device to be displaced along a predetermined trajectory relative to the main body, The system comprises an elastic body that connects the main body and the link mechanism, and biases the contact device to a predetermined position relative to the main body via the link mechanism, An unmanned aerial vehicle in which, when the contact device comes into contact with the ceiling, a reaction force from the ceiling and a restoring force of the elastic body acting in the opposite direction to the reaction force act on the contact device as it is displaced as a result of the contact.

2. The unmanned aerial vehicle according to claim 1, wherein the elastic body is arranged to form an acute angle with respect to the top surface of the main body.

3. The unmanned aerial vehicle according to claim 1, wherein the trajectory is a straight trajectory.

4. The aforementioned link mechanism has parallel links, The displacement of the contact device along a predetermined trajectory is achieved by attaching the contact device to one end of a pair of parallel links in the parallel link. The unmanned aerial vehicle according to claim 1, wherein the elastic body is attached to the other end of either of the pair of links.

5. The unmanned aerial vehicle according to claim 1, wherein the contact device is a work device for performing a predetermined task that involves contact with the ceiling.

6. The unmanned aerial vehicle according to claim 5, wherein the contact device is a fire alarm inspection device.

7. The unmanned aerial vehicle according to claim 1, wherein the unmanned aerial vehicle is a multirotor.

8. The unmanned aerial vehicle according to claim 1, wherein the elastic body is a spring.

9. The unmanned aerial vehicle according to claim 8, wherein the constant and natural length of the spring are determined according to the weight of the contact device.

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