Wind Speed ​​Measurement System

Abstract

To provide a wind velocity measurement system capable of securely and accurately measuring a wind velocity in the upper air by using a flying body.SOLUTION: A wind velocity measurement system 100 includes: a flying body 110 having a hovering function; a camera 120 mounted on the flying body 110; an inclinometer 130 provided in a photographing range of the camera 120; and a wind velocity calculation device 150 for converting inclination of the flying body 110 into a wind velocity. The inclination is detected from an image of the inclinometer 130, which has been taken by the camera 120 during hovering of the flying body 110.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a wind speed measurement system that uses an aircraft to measure wind speed in the sky. [Background technology]

[0002] When working at height on overhead power transmission equipment or inspecting electric wires, the wind speed in the sky is estimated. In doing so, the wind speed on the ground is taken into account as a natural wind speed increase in the sky (a power exponent of 1 / 8 of the maximum instantaneous wind speed) or is estimated from the movement of the branches and leaves of tall trees. However, there is a significant margin of error between the wind speed increase in the sky and the actual wind speed, as the speed increase is also affected by the local topography. Also, estimates based on the movement of the branches and leaves of tall trees are empirical and not accurate. Furthermore, the height of trees is often shorter than the power transmission equipment, so the wind speed at the desired height is not represented.

[0003] Therefore, in order to accurately measure the wind speed in the sky, it is possible to install an anemometer on a steel tower or a Doppler soda on the ground. However, these methods are expensive and not practical. In recent years, a method of measuring the wind speed in the sky using a flying object, so-called a drone, which has become very high-performance and low-cost, has been considered.

[0004] For example, Patent Document 1 discloses a simple anemometer using a rotorcraft (an aircraft such as a drone or a multicopter). Patent Document 1 describes that the simple anemometer includes a rotorcraft with a GPS, and calculates wind speed in the sky from the inclination of the rotorcraft's fuselage and absolute speed based on a GPS signal. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-172258 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the simplified anemometer in Patent Document 1, no specific configuration for acquiring the inclination of the aircraft is disclosed. Also, it is a known configuration that a rotary-wing aircraft has a GPS. Therefore, even if Patent Document 1 is referred to, it is not possible to reproduce the simplified anemometer using a rotary-wing aircraft (drone).

[0007] An object of the present invention is to provide a wind speed measurement system capable of reliably and accurately measuring wind speed in the sky using an aircraft. [Means for solving the problem]

[0008] In order to solve the above problems, a typical configuration of a wind speed measurement system according to the present invention is characterized in that it comprises an aircraft with a hovering function, a camera mounted on the aircraft, an inclinometer arranged within the camera's shooting range, and a wind speed calculation device that converts the inclination of the aircraft detected from an image of the inclinometer captured by the camera while the aircraft is hovering into wind speed.

[0009] The aircraft of the above wind speed measurement system can grasp three-dimensional coordinates based on GPS signals and can stably hover at a fixed position while remaining stationary. At this time, if there is wind blowing in the sky, the aircraft will tilt its body upwind to maintain its position and hover while resisting the wind pressure.

[0010] In this case, the flying object tilts according to the wind speed, so by photographing the inclinometer with a camera mounted on the flying object, the inclination of the flying object can be grasped from the image of the inclinometer. Then, by converting the inclination of the flying object into wind speed with a wind speed calculation device, the wind speed in the sky can be calculated. Therefore, it is possible to reliably and accurately measure the wind speed in the sky using the flying object.

[0011] In addition, since aircraft are generally already equipped with cameras, the only new equipment added to the aircraft in the above-mentioned wind speed measurement system is the inclinometer. Since the inclinometer is a low-cost device, the cost of the wind speed measurement system does not increase. In addition, since the inclinometer is not affected by the wind pressure of the aircraft's propeller, the above-mentioned wind speed measurement system can calculate the wind speed in the sky with high accuracy.

[0012] In order to solve the above problems, another configuration of the wind speed measurement system of the present invention is characterized in that it comprises an aircraft having a hovering function, an acceleration sensor that detects the inclination of the aircraft, and a wind speed calculation device that converts the inclination of the aircraft detected by the acceleration sensor while the aircraft is hovering into wind speed.

[0013] With this configuration, it is also possible to calculate the wind speed in the sky using the tilt of the flying object detected by the acceleration sensor. In recent years, flying objects equipped with acceleration sensors have become more and more common, so with this configuration, it is possible to realize a wind speed measurement system without requiring any new equipment. Effect of the Invention

[0014] According to the present invention, it is possible to provide a wind speed measurement system that can reliably and accurately measure wind speed in the sky using an aircraft. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic diagram of a wind speed measurement system according to an embodiment of the present invention. [Diagram 2] 1 is a diagram illustrating the inclination of the flying object during flight and the inclination of the liquid surface of the inclinometer. FIG. [Diagram 3] 1 is a diagram illustrating an image captured by a camera and conversion of the inclination angle of an aircraft to wind speed. [Figure 4] FIG. 11 is a diagram illustrating another configuration of the wind speed measurement system of the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. The dimensions, materials, and other specific values ​​shown in the embodiment are merely examples for facilitating understanding of the invention, and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same functions and configurations are given the same reference numerals to avoid repeated explanations, and elements not directly related to the present invention are not shown.

[0017] 1 is a schematic diagram of a wind speed measurement system 100 according to this embodiment. As shown in FIG. 1, the wind speed measurement system 100 according to this embodiment includes an aircraft 110, a camera 120, an inclinometer 130, a controller 140, and a wind speed calculation device 150.

[0018] The flying object 110 has the advantage that it can be easily controlled regardless of the user's level of skill, and that it is highly portable and therefore suitable for use in on-site surveys of construction work, etc. Therefore, the wind speed in the sky can be easily measured by flying and hovering the flying object 110 at a location where the wind speed is to be ascertained before working at height or inspecting electric wires.

[0019] 1, the flying object 110 includes a main body 112 and a propeller 114 attached to the main body 112. In this embodiment, the flying object 110 has a hovering function, and can grasp three-dimensional coordinates based on a GPS signal and remain stationary at a fixed position in the air. The flying object 110 is equipped with a camera 120, which is a photographing device.

[0020] The flying object 110 is also equipped with an inclinometer 130 (also called a tilt sensor) that is placed within the shooting range of the camera 120. The inclinometer 130 is broadly divided into digital and analog types. The analog inclinometer 130 contains liquid 132 inside, and when the flying object 110 tilts, the liquid surface 132a of the liquid 132 tilts. This makes it possible to indicate the tilt of the flying object 110.

[0021] 2 is a diagram illustrating the inclination of the flying object 110 during flight and the inclination of the liquid surface 132a of the inclinometer 130. When wind is blowing in the sky, the flying object 110 hovers while tilting its body upwind to maintain its position and resist the wind pressure. At that time, the flying object 110 tilts according to the wind speed.

[0022] When the wind in the sky is weak, i.e., when the wind speed is low, the attitude of the aircraft 110 will be slightly tilted, as shown in FIG. 2(a). As a result, the liquid surface 132a of the inclinometer 130 will also be slightly tilted. On the other hand, when the wind in the sky is strong, i.e., when the wind speed is high, the attitude of the aircraft 110 will be significantly tilted, as shown in FIG. 2(b). As a result, the liquid surface 132a of the inclinometer 130 will also be significantly tilted. In this way, there is a correlation between the wind speed and the tilt of the attitude of the aircraft 110.

[0023] Referring again to Fig. 1, the above-mentioned flying object 110 is operated by the controller 140. The controller 140 includes an operation unit 142, a data transmission / reception unit 144, and an image transmission unit 146. The operation unit 142 receives operations from a user. Examples of the operation unit 142 include a switch and a joystick.

[0024] The data transmitter / receiver 144 transmits and receives data to and from the flying object 110. For example, the data transmitter / receiver 144 transmits an operation input by a user to the operation unit 142 as an operation signal to the flying object 110, and receives location information transmitted from the flying object 110 and images captured by the camera 120. The image transmitter 146 transmits the images of the camera 120 received by the data transmitter / receiver 144 to the wind speed calculation device 150.

[0025] The wind speed calculation device 150 is connected to the controller 140, for example, via Wi-Fi or the like, and converts the inclination of the flying object 110 detected from an image of the inclinometer 130 captured by the camera 120 while the flying object 110 is hovering into wind speed. The wind speed calculation device 150 includes an image receiving unit 152, an inclination angle calculation unit 154, and a wind speed conversion unit 156.

[0026] The image receiving unit 152 receives an image of the inclinometer 130 captured by the camera 120 mounted on the hovering flying object 110 from the image transmitting unit 146 of the controller 140. The inclination angle calculating unit 154 identifies the angle of the liquid surface 132a of the inclinometer 130 from the image received by the image receiving unit 152, and detects (quantifies) the inclination angle (tilt) of the flying object 110. The wind speed converting unit 156 converts the inclination angle of the flying object 110 detected by the inclination angle calculating unit 154 into wind speed.

[0027] 3 is a diagram illustrating an image captured by camera 120 and conversion of the tilt angle of flying object 110 into wind speed. As shown in FIG. 3(a), an inclinometer 130 and its background image are captured in the image captured by camera 120. Because flying object 110 is tilted, steel tower 102 and electric wires 104 in the background image are tilted, and liquid surface 132a of liquid 132 contained inside inclinometer 130 is also tilted.

[0028] The wind speed conversion unit 156 converts the inclination angle of the flying object 110 into wind speed, based on the inclination angle of the flying object 110 calculated by the inclination angle calculation unit 154, by referring to the relational expression between the inclination of the flying object 110 and the wind speed illustrated in FIG. 3(b). In this manner, in the wind speed measurement system 100 of this embodiment, the camera 120 mounted on the flying object 110 photographs the inclinometer 130, so that the inclination of the flying object 110 can be grasped from the image of the inclinometer 130. Then, the wind speed calculation device 150 converts the inclination of the flying object 110 into wind speed, so that the wind speed in the sky can be calculated. Therefore, it is possible to reliably and accurately measure the wind speed in the sky using the flying object 110.

[0029] Furthermore, in recent years, the flying object 110 is generally equipped with a camera 120. Therefore, in the wind speed measurement system 100, the only device newly added to the flying object 110 is the inclinometer 130, which is a low-cost device. Therefore, the wind speed in the sky can be accurately measured without increasing the cost of the wind speed measurement system 100. Furthermore, the inclinometer 130 is not affected by the wind pressure of the propeller 114 of the flying object 110. Therefore, the wind speed measurement system 100 of this embodiment can calculate the wind speed in the sky with high accuracy.

[0030] As can be seen from Fig. 3(a), in order to correctly obtain the inclination of the flying object 110, the shooting direction needs to be perpendicular to the wind direction. Therefore, when measuring the wind speed, the direction of the flying object 110 is adjusted perpendicular to the wind direction by an operation from the ground. Alternatively, the flying object 110 may be rotated horizontally while hovering to obtain continuous images, and the wind speed may be obtained using the angle at which the inclination of the liquid surface 132a of the inclinometer is greatest.

[0031] Fig. 4 is a diagram for explaining another configuration of the wind speed measurement system of this embodiment. Note that components common to the wind speed measurement system 100 explained using Fig. 1 are given the same reference numerals and explanations are omitted. An aircraft 210 included in the wind speed measurement system 200 shown in Fig. 4 is equipped with an acceleration sensor 230 that detects the inclination of the aircraft 210 instead of the inclinometer 130 of the aircraft 110 in Fig. 1.

[0032] The acceleration sensor 230 detects the inclination of the flying object 210 during hovering. The acceleration sensor 230 can detect acceleration in three axial directions. Since no acceleration due to movement occurs during hovering, only gravitational acceleration is detected, and it can be converted into inclination depending on the direction of the resultant force of acceleration. The inclination of the flying object 210 detected by the acceleration sensor 230 is transmitted to the data transmission / reception unit 144 of the controller 140. The controller 140 transmits the inclination of the flying object 210 received by the data transmission / reception unit 144 to the data transmission unit 246. Then, the data transmission unit 246 transmits the data of the inclination of the flying object 210 to the wind speed calculation device 150.

[0033] In the wind speed calculation device 150, the data receiving unit 252 receives data on the inclination of the flying object 210. Then, the wind speed conversion unit 156 converts the inclination of the flying object 210 detected by the acceleration sensor 230 into wind speed. With this configuration, it is possible to calculate the wind speed in the sky using the inclination of the flying object 210. In recent years, flying objects 210 equipped with acceleration sensors 230 have become more widespread, so with this configuration, it is possible to realize the wind speed measurement system 200 without requiring any new device.

[0034] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an example. It is clear that a person skilled in the art can think of various modified or altered examples within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. [Industrial Applicability]

[0035] The present invention can be used as a wind speed measurement system that uses an aircraft to measure wind speed in the sky. [Explanation of symbols]

[0036] 100...wind speed measurement system, 102...steel tower, 104...electric wire, 110...aircraft, 112...main body, 114...propeller, 120...camera, 130...inclinometer, 132...liquid, 132a...liquid level, 140...controller, 142...operation unit, 144...data transmitter / receiver, 146...image transmitter, 150...wind speed calculation device, 152...image receiver, 154...tilt angle calculation unit, 156...wind speed conversion unit, 200...wind speed measurement system, 210...aircraft, 230...accelerometer, 246...data transmitter, 252...data receiver

Claims

[Claim 1] An aircraft having a hovering function; A camera mounted on the aircraft; An inclinometer disposed within the imaging range of the camera; and a wind speed calculation device that converts the inclination of the flying object detected from an image of the inclinometer taken by the camera while the flying object is hovering into wind speed.

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