Measuring device, projectile, flow velocity detector, and measuring method

Abstract

This disclosure aims to provide a technology that makes it easier to measure the velocity difference between a fixed object and the fluid flowing around it, even when the resistance due to the fluid flow is large, compared to the case where displacement is generated in the direction of the flow due to resistance from the fluid flow. [Solution] The measuring device 120 includes an airfoil member 130 attached to the frame 102 of the flying object 100 and displaced in the width direction by the airflow, a strain gauge 136 for detecting the magnitude of the bending moment generated by the airfoil member 130, and a measuring instrument 124 for measuring the speed difference between the flying object 100 and the atmosphere based on the magnitude of the bending moment.

Description

Technical Field

[0001] The present disclosure relates to a measurement device, a flying object, a flow velocity detector, and a measurement method.

Background Art

[0002] For example, Patent Document 1 discloses a method for measuring wind speed using three elastic plates fixed in directions orthogonal to each other.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the technique of Patent Document 1, the elastic plate deforms in a direction that increases the projected area with respect to the flow direction, so it is difficult to use when the wind speed is high.

[0005] An object of the present disclosure is to provide a technique that facilitates measuring the speed difference between a fixed target and a fluid flowing around the fixed target even when the resistance caused by the fluid flow is large, as compared with the case where displacement is generated in the flow direction under the resistance of the fluid flow.

Means for Solving the Problems

[0006] A measurement device according to a first aspect includes: an airfoil member attached to an outer surface of a fixed target around which a fluid flows, and configured to generate displacement in a direction orthogonal to the fluid flow direction due to the fluid flow; a displacement sensor configured to detect the magnitude of the displacement generated by the airfoil member; and a measuring instrument configured to measure a speed difference between the fixed target and the fluid based on the magnitude of the displacement.

[0007] In this embodiment of the measuring device, an airfoil member attached to the outer surface of a fixed object over which fluid flows generates a displacement in a direction perpendicular to the direction of flow. In this embodiment of the measuring device, the displacement is detected by a displacement sensor, and the velocity difference between the fixed object and the fluid is measured by a measuring instrument.

[0008] In this embodiment, the airfoil member of the measuring device has a smaller projected area with respect to the direction of flow compared to the case where displacement is generated in the direction of flow due to resistance from the fluid flow. Therefore, with this embodiment, it is easier to measure the velocity difference between the fixed object and the fluid flowing around the fixed object, even when the resistance from the fluid flow is large, compared to the case where displacement is generated in the direction of flow due to resistance from the fluid flow.

[0009] In the second embodiment, the measuring device is the same as the measuring device described in the first embodiment, wherein the displacement sensor is attached to the airfoil member.

[0010] In this embodiment of the measuring device, the displacement sensor is attached to the airfoil member. Therefore, with this embodiment of the measuring device, it is easier to increase the response speed to displacement compared to when the displacement sensor is attached to the outer surface of the object being fixed.

[0011] The measuring device in the third embodiment is the measuring device described in the first embodiment, wherein the airfoil member is attached to an elastic body that deforms due to the displacement generated by the airfoil member, and the displacement sensor is attached to the elastic body.

[0012] In this embodiment of the measuring device, the airfoil member is attached to an elastic body that deforms due to the displacement generated by the airfoil member. Furthermore, a displacement sensor is attached to the elastic body. Therefore, this embodiment of the measuring device makes it easier to increase the displacement measurement range compared to the case where the displacement sensor is attached to the airfoil member.

[0013] The measuring device of the fourth embodiment has, in the measuring device described in the third embodiment, a pair of airfoil members that are displaced in opposite directions from each other, with the displacement sensor in between.

[0014] In this embodiment of the measuring device, there is a pair of airfoil members that displace in opposite directions, flanking a displacement sensor. In other words, in this embodiment of the measuring device, the displacement sensor acquires the displacement generated by the aligned airfoil members. Therefore, with this embodiment of the measuring device, it is easier to increase the response speed to displacement compared to the case where there is only one airfoil member to which the displacement sensor is attached.

[0015] The fifth embodiment of the measuring device is the measuring device described in any one of the first to fourth embodiments, wherein the displacement sensor is a strain gauge.

[0016] In this embodiment of the measuring device, a strain gauge is used as the displacement sensor. Therefore, the configuration of this embodiment of the measuring device is simple.

[0017] The sixth embodiment of the flying object has the airfoil member provided on its outer surface, and measures its airspeed using the measuring device described in any one of the first to fifth embodiments.

[0018] In this embodiment of the flying object, airspeed is measured using an airfoil member provided on the outer surface. Therefore, with this embodiment of the flying object, airspeed can be easily measured even when the airspeed is high.

[0019] The seventh embodiment of the flying body is the flying body described in the sixth embodiment, wherein the flying body has a main wing or a tail wing, and the airfoil member is the main wing or tail wing of the flying body.

[0020] In this embodiment, the flying vehicle has a main wing or a tail wing, and the main wing or tail wing is used as an airfoil member to measure airspeed. Therefore, the flying vehicle in this embodiment has a simple structure.

[0021] A flow velocity detector according to an eighth aspect is attached to an outer surface of a fixed object around which a fluid flows, and comprises: an airfoil member that generates displacement in a direction orthogonal to the flow direction of the fluid due to the flow of the fluid; and a displacement sensor that outputs a signal corresponding to the displacement generated by the airfoil member.

[0022] In the flow velocity detector according to this aspect, the airfoil member attached to the outer surface of the fixed object around which the fluid flows generates displacement in a direction orthogonal to the flow direction. In the flow velocity detector according to this aspect, the displacement sensor outputs a signal corresponding to the displacement.

[0023] Here, the airfoil member in the flow velocity detector according to this aspect can easily have a smaller projected area in the flow direction, compared to a case where the airfoil member receives resistance from the fluid flow to generate displacement in the flow direction. Therefore, according to the flow velocity detector of this aspect, even when the resistance due to the fluid flow is large, the velocity difference between the fixed object and the fluid flowing around the fixed object can be easily detected, compared to the case where displacement is generated in the flow direction by receiving resistance from the fluid flow.

[0024] A measurement method according to a ninth aspect performs: detecting, by a displacement sensor, displacement that an airfoil member attached to an outer surface of a fixed object around which a fluid flows generates in a direction orthogonal to the flow direction of the fluid due to the fluid flow; and measuring the velocity difference between the fixed object and the fluid based on the output of the displacement sensor.

[0025] In the measurement method according to this aspect, the displacement generated by the airfoil member attached to the outer surface of the fixed object around which the fluid flows in the direction orthogonal to the flow direction is detected by the displacement sensor. Further, the velocity difference between the fixed object and the fluid flow is measured based on the output of the displacement sensor.

[0026] Therefore, according to the measurement method of this aspect, even when the resistance due to the fluid flow is large, the velocity difference between the fixed object and the flow of the fluid flowing around the fixed object can be easily measured. Effects of the Invention

[0027] According to this disclosure, a technique is provided that makes it easier to measure the velocity difference between a fixed object and the fluid flowing around it, even when the resistance due to the fluid flow is large, compared to the case where displacement is generated in the direction of the flow due to resistance from the fluid flow. [Brief explanation of the drawing]

[0028] [Figure 1] This is a diagram illustrating the projectile related to this disclosure. [Figure 2] This is a perspective view illustrating a measuring device according to a first embodiment of the present disclosure, showing the measuring device attached to a flying object. [Figure 3] This is a diagram illustrating a measuring device according to a first embodiment of the present disclosure, and is a front view showing the measuring device attached to a flying object. [Figure 4] This figure illustrates a measuring device according to a second embodiment of the present disclosure, and is a front view showing the measuring device attached to a flying object. [Figure 5] This is a diagram illustrating a measuring device according to a third embodiment of the present disclosure, and is a perspective view illustrating a flying object. [Figure 6] This is a diagram illustrating a measuring device according to a fourth embodiment of the present disclosure, and is a front view showing the measuring device attached to a flying object. [Modes for carrying out the invention]

[0029] An example of an embodiment of this disclosure will be described below with reference to the drawings. Note that the dimensional ratios in the drawings are exaggerated for illustrative purposes and may differ from the actual ratios.

[0030] In each drawing, arrow FR indicates the direction of flight of the projectile, which is the forward direction of the projectile. Arrow RR indicates the direction opposite to the direction of flight of the projectile, which is the backward direction of the projectile. Arrow W indicates the direction perpendicular to the direction of flight of the projectile, which is the width direction of the projectile. Arrow UP indicates the direction that is above the projectile when it is in flight, which is the upward direction of the projectile.

[0031] Furthermore, arrows FR and RR indicate the direction in which the atmosphere moves relative to the flying object. Specifically, arrow RR indicates the direction in which the atmosphere flows relative to the flying object. In other words, the speed of the atmosphere flowing in the direction of arrow RR as viewed from the flying object is the airspeed.

[0032] [First Embodiment] (composition) (100 flying objects) Figure 1 shows a flying object 100 according to this disclosure. The flying object 100 is, for example, a small flying object that is controlled by radio control.

[0033] As shown in Figure 1, the flying object 100 is a fixed-wing flying object comprising a fuselage 104, a main wing 106, and a tail wing 108.

[0034] The fuselage 104 is roughly cylindrical in shape due to the frame 102, and houses an energy source (for example, fuel or batteries) for driving the flying object 100.

[0035] The main wing 106 is a member that extends in the width direction in front of the fuselage 104 in the direction of flight (i.e., the direction in which the projectile 100 moves relative to the ground). The main wing 106 is a member that generates lift for the projectile 100 as it moves in the direction of flight.

[0036] The tail fin 108 is located at the rear of the fuselage 104 in the direction of flight and is a component that controls the attitude of the flying object 100 during flight, as well as performing steering. The tail fin 108 comprises a horizontal stabilizer 114 extending in the width direction and a vertical stabilizer 112 extending in a direction perpendicular to the width direction and the longitudinal direction.

[0037] In this embodiment, the flying object 100 is a so-called propeller airplane. The flying object 100 obtains thrust by having a power source (not shown) rotate the propeller to move forward. The flying object 100 then obtains lift based on the relative motion with the atmosphere flowing around the main wing 106 and flies.

[0038] Furthermore, the projectile 100 is equipped with a measuring device 120 for measuring airspeed. In this embodiment, the measuring device 120 is mounted on the upper side of the frame 102 of the fuselage 104, as shown in Figure 1. The frame 102 is an example of a "fixed object" in this disclosure. The measuring device 120 according to this disclosure will be described with reference to Figures 2 and 3.

[0039] (Measuring device 120) Figure 2 is a perspective view showing an example of the measuring device 120 according to this embodiment. Figure 3 is a front view of an example of the measuring device 120 according to this embodiment, viewed from the front. As shown in Figure 2, the measuring device 120 according to this embodiment includes a flow velocity detector 122 and a measuring instrument 124.

[0040] (Flow velocity detector 122) The flow velocity detector 122 comprises an elastic plate 132, an airfoil member 130, and a strain gauge 136.

[0041] The elastic plate 132 is, for example, a thin plate made of an elastic material such as metal. As shown in Figures 2 and 3, the elastic plate 132 is attached to the frame 102 of the fuselage 104 of the flying object 100 via the elastomer plate 116. More specifically, the elastic plate 132 has its thickness direction in the direction that overlaps with the elastomer plate 116 (i.e., the vertical direction). For example, the elastic plate 132 is bonded to the elastomer plate 116.

[0042] The elastomer plate 116 is made of a material that allows for the elastic deformation of the elastic plate 132. The elastomer plate 116 can be appropriately selected from, for example, rubber-based materials such as natural rubber and synthetic rubber, as well as materials having a structure that includes liquid or air, such as gels and foams.

[0043] The elastic plate 132 may be made of any material, but it is preferable that it be made of a material with high elastic deformability and low hysteresis. Furthermore, since the elastic plate 132 is mounted on the flying object 100, it is preferable that it be lightweight. As an example, the elastic plate 132 is preferably made of a material referred to as a light metal such as aluminum or magnesium, or an alloy thereof.

[0044] As shown in Figures 2 and 3, the airfoil member 130 extends in the front-rear direction and is attached to the elastic plate 132 in the thickness direction of the elastic plate 132. In other words, the airfoil member 130 is attached to the frame 102 via the elastic plate 132.

[0045] Furthermore, when viewed from above, the airfoil member 130 extends in the front-to-back direction and has a shape that bulges on one side in the width direction. In other words, when the airfoil member 130 receives wind from the front, it generates a force in the width direction. More specifically, when the airfoil member 130 receives wind from the front, it generates a force directed toward the bulging side.

[0046] Furthermore, as shown in Figures 2 and 3, in this embodiment, the airfoil members 130 are provided in pairs side by side in the width direction. In this embodiment, the pair of airfoil members 130 are configured so that the inner side in the width direction is bulging. That is, when the pair of airfoil members 130 receive wind from the front, as shown in the airflow AD, they both generate a force that causes them to tilt inward in the width direction.

[0047] Furthermore, when the pair of airfoil members 130 generate a force that causes them to tilt inward, this inward force is transmitted to the elastic plate 132. Specifically, as shown by the dashed line in Figure 3, when the airfoil members 130 generate a force that causes them to tilt inward in the width direction, the elastic plate 132 generates a bending moment with the front-rear direction as its axis and the upper side being the inward side of the bend. In other words, the elastic plate 132 generates a bending moment that is perpendicular to the direction of airflow. To put it another way, a bending moment is generated with the direction of airflow as its axis and perpendicular to the outer surface of the frame 102, which is the object to be fixed. Note that the bending moment described in this embodiment is an example of the "displacement" described herein.

[0048] In this embodiment, the airfoil member 130 may be made of any material, but it is desirable that it be made of a material with high rigidity. Also, since the airfoil member 130 is mounted on the flying body 100, it is preferable that it be lightweight. As an example, the airfoil member 130 is preferably made of a material called a light metal such as aluminum or magnesium, or an alloy thereof.

[0049] The strain gauge 136 is attached to the upper surface of the elastic plate 132, as shown in Figures 2 and 3. The strain gauge 136 is a mechanical sensor whose resistance changes when subjected to a bending moment, and outputs the bending deformation in the elastic plate 132 as a change in electrical resistivity. In other words, the strain gauge 136 detects the bending moment generated in the elastic plate 132 by the airfoil member 130. The method of attaching the strain gauge 136 to the elastic plate 132 is not particularly limited, but as an example, the strain gauge 136 is bonded to the elastic plate 132.

[0050] (Measuring instrument 124) The measuring instrument 124 measures the magnitude of the bending moment generated in the elastic plate 132, as detected by the strain gauge 136. More specifically, it measures the magnitude of the bending moment applied to the member to which the strain gauge 136 is attached, i.e., the elastic plate 132, by amplifying and measuring the change in electrical resistivity output by the strain gauge 136. The method of connecting the strain gauge 136 and the measuring instrument 124 is not particularly limited.

[0051] Here, the magnitude of the bending moment generated in the elastic plate 132 depends on the strength of the wind acting on the airfoil member 130, that is, the velocity difference between the projectile 100 and the surrounding atmosphere shown in the airflow AD. In other words, the magnitude of the bending moment detected by the strain gauge 136 depends on the airspeed of the projectile 100. Therefore, the measuring instrument 124 can measure the airspeed of the projectile 100 based on the magnitude of the bending moment detected by the strain gauge 136.

[0052] Next, a method for measuring the airspeed of the projectile 100 related to this disclosure will be described.

[0053] (Method for measuring airspeed) When the projectile 100 in this embodiment flies forward, the projectile 100 experiences resistance from front to rear based on the speed difference with the atmosphere. As a result, air flows relatively from front to rear to the airfoil member 130 of the measuring device 120 attached to the outer surface of the frame 102.

[0054] In other words, when the flying object 100 flies forward, a bending moment occurs in the airfoil member 130, causing it to bend in the width direction as described above. The strain gauge 136 detects this bending moment, and based on the detection result, the measuring instrument 124 measures the airspeed.

[0055] Next, the operation and effects of the measuring device 120, the projectile 100, the flow velocity detector 122, and the flow velocity measurement method in this embodiment will be explained.

[0056] (Mechanism of Action and Effects) In this embodiment, the measuring device 120 generates a bending moment in the width direction, which is perpendicular to the airflow AD, through an airfoil member 130 attached to the outer surface of the frame 102 via an elastic plate 132. The bending moment generated in the airfoil member 130 is detected by a strain gauge 136 attached to the elastic plate 132. The measuring instrument 124 then measures the speed difference between the flying object 100 and the air, i.e., the airspeed, based on the magnitude of the detected bending moment.

[0057] In this embodiment, the airfoil member 130 in the measuring device 120 is more likely to have a smaller projected area when viewed from the front-rear direction compared to the case where it receives resistance from the airflow AD and generates a bending moment toward the rear. Therefore, the measuring device 120 makes it easier to measure airspeed even when the resistance due to the airflow is large, that is, when the airspeed of the flying object 100 is high.

[0058] Furthermore, in the measuring device 120, the strain gauge 136 is attached to the outer surface of the elastic plate 132. Therefore, the measuring device 120 makes it easier to widen the measurement range of the bending moment compared to when the strain gauge 136 is attached to the airfoil member 130. In other words, the measuring device 120 makes it easier to widen the measurement range of airspeed.

[0059] In the measuring device 120 according to this embodiment, the strain gauge 136 on the elastic plate 132 is mounted between the airfoil members 130 that are aligned in the width direction. In other words, in the measuring device 120 according to this embodiment, the strain gauge 136 acquires the bending moment generated by the aligned airfoil members 130.

[0060] Therefore, according to the measuring device 120 in this embodiment, it is easier to increase the response speed to bending moment compared to the case where there is only one airfoil member 130.

[0061] Furthermore, the measuring device 120 uses a strain gauge 136 as a bending moment sensor. Therefore, the measuring device 120 according to this embodiment has a simple configuration.

[0062] Furthermore, in the flow velocity detector 122, the airfoil member 130, which is attached to the frame 102 of the flying object 100 via an elastic plate 132, generates a bending moment in the width direction. In this embodiment of the flow velocity detector 122, the bending moment is detected by a strain gauge 136 attached to the elastic plate 132.

[0063] In this embodiment, the airfoil member 130 in the flow velocity detector 122 is more likely to have a smaller projected area when viewed from the front-rear direction compared to the case where it receives resistance from the airflow and generates a bending moment toward the rear. Therefore, the measuring device 120 can easily detect the airspeed even when the resistance due to the airflow AD is large, that is, when the airspeed of the flying object 100 is large.

[0064] <Variations> In this embodiment, the strain gauge 136 was attached to the upper surface of the airfoil member 130. In this embodiment, the strain gauge 136 may also be attached to the lower surface of the airfoil member 130.

[0065] Furthermore, in the examples shown in Figures 1 to 3, the pair of airfoil members 130 are shaped so that the inner side in the width direction is bulging, thereby generating a force that causes them to collapse inward. The orientation of the airfoil members 130 is not limited to this; they may also be shaped so that the outer side in the width direction is bulging, thereby generating a force that causes them to collapse outward. In this case, the direction of the bending moment generated in the elastic plate 132 will be the opposite of that described above.

[0066] Furthermore, although a pair of airfoil members 130 were provided in the examples shown in Figures 1 to 3, the airfoil members 130 may be provided only in one direction in the width direction, as long as it does not affect the flight performance of the flying object 100.

[0067] Furthermore, in the examples shown in Figures 1 to 3, the elastic plate 132 of the measuring device 120 was attached to the frame 102 via an elastomer plate 116, but the configuration of the measuring device 120 in this embodiment is not limited to this. As described above, the configuration does not hinder the bending deformation of the elastic plate 132 by the airfoil member 130, and the configuration does not include the elastomer plate 116. For example, the elastic plate 132 may be attached to the frame 102 via a suitable spacer.

[0068] Next, the measuring device 220 according to the second embodiment of this disclosure will be described with reference to Figure 4. In the second embodiment, components similar to those in the first embodiment will be given the same names and reference numerals as in the first embodiment, and detailed descriptions will be omitted.

[0069] [Second Embodiment] (composition) Figure 4 shows a front view of the measuring device 220 according to the second embodiment. The measuring device 220 according to this embodiment includes a rigid plate 232, an airfoil member 230, and a strain gauge 136 as a flow velocity detector 222.

[0070] (Flow velocity detector 222) The rigid plate 232 is, for example, a thin plate made of an elastic material such as metal. As shown in Figure 4, the rigid plate 232 is attached to the frame 102 of the fuselage 104 of the flying vehicle 100.

[0071] The rigid plate 232 may be made of any material, but it is preferable that it be made of a material that is highly rigid and lightweight. As an example, the rigid plate 232 is preferably made of a material called a light metal such as aluminum or magnesium, or an alloy thereof.

[0072] In this embodiment, the airfoil member 230 may be made of any material, but it is preferable that it be made of a material with high elastic deformability and low hysteresis. Furthermore, since the airfoil member 230 is mounted on the flying body 100, it is preferable that it be lightweight. As an example, the airfoil member 230 is preferably made of a material referred to as a light metal such as aluminum or magnesium, or an alloy thereof.

[0073] Furthermore, in the measuring device 220 according to this disclosure, the strain gauge 136 is attached to the airfoil member 230. More specifically, the strain gauge 136 is attached to the outer side in the width direction of the airfoil member 230. The method of attaching the strain gauge 136 to the airfoil member 230 is not particularly limited, but as an example, the strain gauge 136 is bonded to the airfoil member 230.

[0074] The other configurations are the same as in the first embodiment. In this embodiment as well, the airfoil member 230 generates a force directed inward in the width direction when it receives wind from the front. Here, as shown in Figure 4, the lower end of the airfoil member 230 is attached to the rigid plate 232, so the airfoil member 230 itself is also subjected to a bending moment by the force generated when it receives wind. In other words, a bending moment is generated in the airfoil member 230 with the direction of airflow as its axis and in a direction perpendicular to the outer surface of the frame 102, which is the object it is fixed to.

[0075] Furthermore, in this embodiment, the airfoil member 230 deforms itself due to a force directed inward in the width direction. More specifically, as shown by the dashed line in Figure 4, the airfoil member 230 in this embodiment undergoes bending deformation inward in the width direction when subjected to wind from the front.

[0076] Furthermore, the magnitude of the bending moment generated in the airfoil member 230 depends on the strength of the wind acting on the airfoil member 230. In other words, the magnitude of the bending moment detected by the strain gauge 136 depends on the airspeed of the flying object 100.

[0077] In other words, the measuring device 220 according to this embodiment measures the airspeed as the magnitude of the bending moment, similar to the measuring device 220 according to the first embodiment. Therefore, in this embodiment as well, the airspeed can be measured using the same measurement method as in the first embodiment.

[0078] Next, the operation and effects of the measuring device 220, the projectile 100, the flow velocity detector 222, and the flow velocity measurement method in this embodiment will be explained.

[0079] (Mechanism of Action and Effects) In this embodiment as well, the measuring device 220 generates a bending moment in the airfoil member 230 in a direction perpendicular to the airflow AD. Specifically, the bending moment generated in the airfoil member 230 is directed in the width direction. In this embodiment of the measuring device 220, the bending moment is detected by a strain gauge 136 attached to the airfoil member 230, and the speed difference between the frame 102 and the atmosphere is measured by the measuring instrument 124.

[0080] Therefore, in this embodiment as well, the airfoil member 230 in the measuring device 220 is more likely to have a smaller projected area when viewed from the front-rear direction compared to the case where it receives resistance from the airflow AD and generates a bending moment toward the rear. For this reason, the measuring device 220 makes it easier to measure airspeed even when the resistance from the airflow AD is large, that is, when the airspeed of the flying object 100 is high.

[0081] Furthermore, in the measuring device 220 according to this embodiment, the strain gauge 136 is attached to the airfoil member 230. Therefore, the measuring device 220 makes it easier to increase the response speed to bending moment compared to the case where the strain gauge 136 is attached to the rigid plate 232.

[0082] In this embodiment as well, the same operation and effects as in the first embodiment can be obtained based on the same configuration as in the first embodiment.

[0083] <Variations> In this embodiment, the strain gauge 136 was attached to the outer surface of the airfoil member 230. However, the configuration of the measuring device 220 in this embodiment is not limited to this, and it may also be attached to the inner surface of the airfoil member 230.

[0084] Furthermore, in the example shown in Figure 4, the pair of airfoil members 230 are shaped so that the inner side in the width direction is bulging, thereby generating a bending moment that causes them to bend inward. The orientation of the airfoil members 230 is not limited to this; they may also be shaped so that the outer side in the width direction is bulging, thereby generating a bending moment that causes them to bend outward.

[0085] Furthermore, in the example shown in Figure 4, the strain gauge 136 was attached to only one of the airfoil members 230, but it may also be attached to both of the pair of airfoil members 230. Also, the airfoil members 230 may be attached to only one side in the width direction, as long as it does not affect the flight performance of the flying object 100.

[0086] Next, the measuring device 320 according to the third embodiment of this disclosure will be described with reference to Figure 5. In the third embodiment, components similar to those in the first or second embodiment will be given the same names and reference numerals as in the first or second embodiment, and detailed descriptions will be omitted.

[0087] [Third Embodiment] (composition) Figure 5 shows a flying object 100 having the measuring device 320 in this embodiment. As shown in Figure 5, in this embodiment, the strain gauge 136 is attached to the horizontal stabilizer 114. The horizontal stabilizer 114 then undergoes an upward bending deformation when subjected to wind from the front.

[0088] In other words, in this embodiment, the horizontal stabilizer 114 is an example of the "airfoil member" of this disclosure. For this reason, in this embodiment, the horizontal stabilizer 114 constitutes the flow velocity detector 322 and measuring device 320 of this disclosure. Also, in this embodiment, the frame 102 of the fuselage 104 is an example of the "fixed object" of this disclosure.

[0089] The other configurations are the same as in the first or second embodiment. The measuring device 320 according to this embodiment measures the airspeed based on the magnitude of the bending moment generated in the horizontal tail fin 114, similar to the measuring device 320 according to the second embodiment. Therefore, in this embodiment as well, the airspeed can be measured using the same measurement method as in the second embodiment.

[0090] Next, the operation and effects of the measuring device 320, the projectile 100, the flow velocity detector 322, and the flow velocity measurement method in this embodiment will be explained.

[0091] (Mechanism of Action and Effects) In this embodiment as well, the measuring device 320 generates a bending moment in the horizontal stabilizer 114 in a direction perpendicular to the airflow AD. Specifically, the bending moment generated in the horizontal stabilizer 114 is directed upward. In other words, in the measuring device 320 according to this embodiment, the horizontal stabilizer 114 can have a smaller projected area when viewed from the front-rear direction compared to the case where it is subjected to the resistance of the airflow AD and generates a bending moment towards the rear.

[0092] Therefore, according to the measuring device 320 in this embodiment, it is easy to measure the airspeed even when the resistance due to the airflow AD is large, that is, when the airspeed of the flying object 100 is large.

[0093] <Variations> In this embodiment, the strain gauge 136 was attached to the horizontal stabilizer 114. However, the configuration of the measuring device 320 in this embodiment is not limited to this. That is, the strain gauge 136 may be attached to the main wing 106. Also, if the vertical stabilizer 112 generates a bending moment in the width direction (i.e., if the vertical stabilizer 112 is not symmetrical in the width direction), the strain gauge 136 may be attached to the vertical stabilizer 112.

[0094] Furthermore, in the description of this embodiment, the strain gauge 136 may be attached to the frame 102 of the fuselage 104. Also, similar to the measuring device 320 in the first embodiment, the airspeed may be measured based on the magnitude of the bending moment applied to the frame 102 of the fuselage 104.

[0095] Next, the measuring device 420 according to the fourth embodiment of this disclosure will be described with reference to Figure 6. In the fourth embodiment, components similar to those in the first to third embodiments will be given the same names and reference numerals as in the first to third embodiments, and detailed descriptions will be omitted.

[0096] [Fourth Embodiment] (composition) Figure 6 shows the measuring device 420 in this embodiment. The measuring device 420 in this embodiment includes a rigid plate, an elastic plate 432, an airfoil member 430, and a strain gauge 136 as a flow velocity detector 422.

[0097] (Flow velocity detector 422) The elastic plate 432 is, for example, a thin plate made of an elastic material such as metal. As shown in Figure 6, the elastic plate 432 extends in the front-rear direction and is attached to the rigid plate 232 in the thickness direction. Furthermore, a pair of elastic plates 432 are provided side by side in the width direction. That is, the elastic plate 432 is attached to the frame 102 via the rigid plate 232. The specific configuration of the rigid plate 232 is the same as in the second embodiment. Also, the specific material of the elastic plate 432 is the same as in the second embodiment.

[0098] In this embodiment, the airfoil member 430 is provided at the upper end of a pair of adjacent elastic plates 432, extending in the width direction, as shown in Figure 6. Furthermore, the airfoil member 430 is positioned so that the upper side bulges out when viewed from the front of the flying object 100. That is, when the airfoil member 430 receives wind from the front, it generates an upward force. The specific material of the airfoil member 430 is the same as in the first or second embodiment.

[0099] Furthermore, in the measuring device 420 according to this disclosure, the strain gauge 136 is attached to the elastic plate 432. More specifically, the strain gauge 136 is attached to the outer side in the width direction of the elastic plate 432. The method of attaching the strain gauge 136 to the elastic plate 432 is not particularly limited, but as an example, the strain gauge 136 is bonded to the elastic plate 432.

[0100] The other components are the same as those in the second embodiment.

[0101] In this embodiment, the airfoil member 430 generates an upward force when it receives wind from the front. Here, as shown in Figure 6, the lower end of the airfoil member 430 is provided so as to extend over the elastic plate 432, and an upward force is applied to the elastic plate 432.

[0102] In this embodiment, the elastic plate 432 receives a tensile load between the rigid plate 232 and the airfoil member 430 due to an upward force. That is, when the airfoil member 430 in this embodiment receives wind from the front, it undergoes tensile deformation upward.

[0103] Furthermore, the magnitude of the tensile deformation occurring in the elastic plate 432 depends on the wind strength acting on the airfoil member 430. In other words, the magnitude of the displacement detected by the strain gauge 136 depends on the airspeed of the flying object 100.

[0104] In other words, the measuring device 420 according to this embodiment measures the air velocity as the magnitude of the displacement of the elastic plate 432. Therefore, the air velocity can be measured in this embodiment as well.

[0105] (Mechanism of Action and Effects) In this embodiment as well, the same operation and effects as in the first or second embodiment can be obtained based on the same configuration as in the first or second embodiment.

[0106] <Variations> In this embodiment, as described above, the airfoil member 430 generated an upward force. The configuration of the flow velocity detector 422 in this embodiment is not limited to this, and the airfoil member 430 may generate a downward force. That is, the elastic plate 432 may measure the airspeed by measuring the compressive load.

[0107] [Other embodiments] Furthermore, although the above description uses a strain gauge 136 as the displacement sensor, the technology relating to this disclosure is not limited to this, as long as it is possible to measure the displacement generated by the airfoil member 430. For example, any sensor capable of measuring displacement may be used, such as a load cell or a photoelastic sensor.

[0108] Furthermore, in the above description, the flying object 100 was described as a fixed-wing flying object 100 having a main wing 106 and a tail wing 108. However, the technology relating to this disclosure is not limited thereto. For example, the measuring device 420 relating to this disclosure may also be attached to the outer surface of a rotary-wing flying object. Alternatively, for example, the measuring device 420 relating to this disclosure may be configured as a third embodiment of the rotary-wing flying object having a tail wing 108.

[0109] Furthermore, in the above description, the measuring device 420 was attached to the projectile 100 to measure the airspeed of the projectile 100. However, the technology relating to this disclosure is not limited thereto. For example, the measuring device 420 relating to this disclosure may be attached to an object fixed to the ground to measure wind speed. It may also be attached below the waterline on a ship (especially a hydrofoil, etc.) to measure the speed relative to water.

[0110] While embodiments of this disclosure have been described above with reference to the attached drawings, it is clear that any person with ordinary skill in the art to which this disclosure belongs could conceive of various modifications or applications within the scope of the technical idea described in the claims, and these too are naturally understood to fall within the technical scope of this disclosure. [Explanation of symbols]

[0111] 100 Projectile 102 frames (an example of a fixed object) 104 Torso (Example of a fixed object) 106 Main wing (an example of an airfoil component) 108 Tail wing 112 Vertical stabilizer 114 Horizontal stabilizer (an example of an airfoil component) 116 Elastomer sheet 120 Measuring device 122 Flow velocity detector 124 Measuring instruments 130 Airfoil Member 132 Elastic plate (an example of an elastic body) 136. Strain gauge (an example of a displacement sensor) 220 Measuring device 222 Flow velocity detector 230 Airfoil Member 232 Rigid plate 320 Measuring devices 322 Flow velocity detector 420 Measuring devices 422 Flow velocity detector 430 Airfoil Member 432 Elastic plate (an example of an elastic body)

Claims

1. An airfoil member attached to the outer surface of a fixed object around which fluid flows, which causes displacement in a direction perpendicular to the direction of fluid flow due to the fluid flow, A displacement sensor that outputs a signal corresponding to the displacement generated by the airfoil member, A measuring instrument that measures the velocity difference between the fixed object and the fluid based on the output of the displacement sensor, A measuring device equipped with the following features.

2. The displacement sensor is attached to the airfoil member. A measuring device according to claim 1.

3. The airfoil member is attached to an elastic body that deforms due to the displacement caused by the airfoil member. The displacement sensor is attached to the elastic body. A measuring device according to claim 1.

4. The airfoil members have a pair that are displaced in opposite directions from each other, with the displacement sensor in between. A measuring device according to claim 3.

5. The displacement sensor is a strain gauge. A measuring device according to claim 1.

6. The airfoil member is provided on the outer surface, The airspeed is measured using the measuring device described in any one of claims 1 to 5. Flying object.

7. The aforementioned flying object has a main wing or a tail wing, The airfoil member is the main wing or tail wing of the flying vehicle. A projectile according to claim 6.

8. An airfoil member is attached to the outer surface of a fixed object around which fluid flows, and generates displacement in a direction perpendicular to the direction of fluid flow due to the fluid flow, A displacement sensor that outputs a signal corresponding to the displacement generated by the airfoil member, A flow velocity detector equipped with the following features.

9. The displacement of an airfoil member attached to the outer surface of a fixed object, which is surrounded by a fluid flow, is detected by a displacement sensor in a direction perpendicular to the fluid flow direction due to the fluid flow. Based on the output of the displacement sensor, the velocity difference between the fixed object and the fluid is measured, A measurement method for performing this measurement.

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