Patent Publication Number: US-2023137157-A1

Title: Flight vehicle and continuity test method

Description:
TECHNICAL FIELD 
     The present invention relates to an aerial vehicle and an electrical connectivity inspecting method. The present invention particularly relates to an aerial vehicle comprising a conductive member for contacting a conductor of a structure, and an electrical connectivity inspecting method using such an aerial vehicle. 
     BACKGROUND ART 
     Tall structures such as steel poles of a power line, high-rise buildings, and blades of a wind turbine, etc. are equipped with measures against lightning strikes. For example, a receptor for receiving a lightning strike (metal lightning receiving unit) and a down conductor are provided to a blade of a wind turbine. Meanwhile, electrical connectivity of receptors and down conductors needs to be inspected in buildings equipped with such a measure against lightning strikes. 
     If, for example, an electrical connection between a receptor and ground via a down conductor is not secured on a blade of a wind turbine, lightning strike on the receptor could generate a spark to damage the wind turbine blade, etc. Thus, electrical connectivity of the receptors, etc. (including down conductors) needs to be inspected. 
     SUMMARY OF INVENTION 
     Technical Problem 
     However, it was necessary in the past to inspect electrical connectivity of a receptor, etc. on a wind turbine blade which is still attached to a hub of a wind turbine manually at a high elevation. Thus, electrical connectivity of a receptor, etc. could not be readily inspected as the inspection entails a high level of risk. 
     The objective of the present invention is to provide an aerial vehicle that enables safe and simple electrical connectivity inspection on a structure and an electrical connectivity inspecting method using such an aerial vehicle. 
     Solution to Problem 
     The present invention provides the following items. 
     Item 1 
     An aerial vehicle, comprising: 
     an aerial vehicle body; 
     a conductive member for contacting a conductor of a structure; and 
     a moving mechanism capable of moving the conductive member between a distal position and a proximal position of the aerial vehicle body. 
     Item 2 
     The aerial vehicle of item 1, wherein the moving mechanism comprises: 
     a support rod for supporting the conductive member; and 
     rod moving means capable of moving the support rod to a distal direction. 
     Item 3 
     The aerial vehicle of item 1, wherein the moving mechanism comprises: 
     an extendable/retractable support rod for supporting the conductive member; and 
     rod extending/retracting means for extending/retracting the support rod. 
     Item 4 
     The aerial vehicle of item 3, wherein the extendable/retractable support rod comprises at least: 
     a first rod coupled to the conductive member; and 
     a second rod for protrudably and embeddably housing the first rod. 
     Item 5 
     The aerial vehicle of any one of items 2 to 4, wherein the conductive member and the support rod are coupled with a coupling member so that a posture of the conductive member can be changed in any manner. 
     Item 6 
     The aerial vehicle of item 5, wherein 
     the coupling member comprises a plurality of flexible members, and 
     the plurality of flexible members are disposed with a given angular interval axially about the support rod. 
     Item 7 
     The aerial vehicle of item  5 , wherein the coupling member is a universal joint. 
     Item 8 
     The aerial vehicle of any one of items 1 to 7, wherein the aerial vehicle further comprises a rotation mechanism for rotating the conductive member. 
     Item 9 
     The aerial vehicle of any one of items 1 to 8, wherein the conductive member comprises at least one of a metal wire netting, a polishing member, a checker plate, a metal scrubber, and a perforated board. 
     Item 10 
     The aerial vehicle of any one of items 2 to 7, wherein the support rod or the conductive member further comprises fixing means for fixing the conductive member to the conductor. 
     Item 11 
     The aerial vehicle of any one of items 1 to 10, wherein the moving mechanism moves a conductive member in a substantially vertical direction of the aerial vehicle body, and the distal position is a position in an upward direction of the substantially vertical direction with respect to the proximal position. 
     Item 12 
     A method of conducting electrical connectivity inspection on the structure by using the aerial vehicle of any one of items 1 to 11, comprising: 
     moving the aerial vehicle to a position below a conductor of the structure while the conductive member is at the proximal position; and 
     contacting the conductive member with the conductor of the structure by moving the conductive member to the distal position to conduct electrical connectivity inspection. 
     Item 13 
     The method of item 12, further comprising: 
     fixing the conductive member to the conductor; 
     detaching the conductive member from the aerial vehicle, while the conductive member is fixed to the conductor, to release the aerial vehicle from the structure; and 
     disengaging fixation of the conductive member to the conductor as of completion of the electrical connectivity inspection to release the conductive member from the structure. 
     Item 14 
     The method of item 12 or 13, wherein the conductor of the structure is a receptor provided at a tip of a wind turbine blade. 
     Advantageous Effects of Invention 
     An aerial vehicle that enables safe and simple electrical connectivity inspection on a structure and an electrical connectivity inspecting method using such an aerial vehicle can be obtained through the present invention. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a perspective view for describing aerial vehicle  100  according to Embodiment 1 of the invention.  FIG.  1 ( a )  shows the outer appearance of the aerial vehicle  100 , and  FIG.  1 ( b )  shows a state in which conductive member  120  is separated from the aerial vehicle  100 . 
         FIG.  2    is a diagram for describing the specific configuration of moving mechanism  130  of the aerial vehicle  100  shown in  FIG.  1   .  FIG.  2 ( a )  is a side view of the aerial vehicle  100  in  FIG.  1    viewed from direction A, and  FIG.  2 ( b )  is a vertical cross-sectional view of housing  110   b  shown in  FIG.  2 ( a ) . 
         FIG.  3    is a diagram for describing a method of inspecting electrical connectivity of a receptor, etc. by using the aerial vehicle  100  shown in  FIG.  1   .  FIG.  3 ( a )  shows ascending and descending motions of the aerial vehicle  100  in  FIG.  1   , and  FIG.  3 ( b )  shows an upward movement of the conductive member  120  of the aerial vehicle  100  in  FIG.  1   . 
         FIG.  4    is a diagram for describing moving mechanism  131  of aerial vehicle  101  according to Modified Example 1 of Embodiment 1.  FIG.  4 ( a )  is a side view of the aerial vehicle  101 , and  FIG.  4 ( b )  is a vertical cross-sectional view of the housing  110   b  shown in  FIG.  4 ( a ) . 
         FIG.  5    is a diagram for describing rotation mechanism  132   d  for rotating the conductive member  120  of aerial vehicle  102  according to Modified Example 2 of Embodiment 1.  FIG.  5 ( a )  is a side view of the aerial vehicle  102 , and  FIG.  5 ( b )  is a vertical cross-sectional view of the housing  110   b  shown in  FIG.  5 ( a ) . 
         FIG.  6    is a perspective view for describing aerial vehicle  200  according to Embodiment 2 of the invention.  FIG.  6 ( a )  shows the outer appearance of the aerial vehicle  200 , and  FIG.  6 ( b )  shows the structure of coupling member  230   c  by separating the conductive member  120  from the aerial vehicle  200 . 
         FIG.  7    is a diagram for describing the specific configuration of moving mechanism  230  of the aerial vehicle  200  shown in  FIG.  6   .  FIG.  7 ( a )  is a side view of the aerial vehicle  200  in  FIG.  6    viewed from direction A, and  FIG.  7 ( b )  is a vertical cross-sectional view of the housing  110   b  shown in  FIG.  7 ( a ) . 
         FIG.  8 A  is a diagram for describing a method of inspecting electrical connectivity of a receptor, etc. by using aerial vehicle  300  according to Embodiment 3 of the invention.  FIG.  8 A (a) shows ascending and descending motions of the aerial vehicle  300 , and  FIG.  8 A (b) shows an operation of fixing the conductive member  120  of the aerial vehicle  300  to a receptor. 
         FIG.  8 B  is a diagram for describing a method of inspecting electrical connectivity of a receptor, etc. by using the aerial vehicle  300  according to Embodiment 3 of the invention.  FIG.  8 B (a) shows an operation of releasing the aerial vehicle  300  from a wind turbine blade while a conductive member is still fixed to a receptor, and  FIG.  8 B (b) shows an operation of disengaging fixation of a conductive member to a receptor to release the conductive member from a wind turbine blade after electrical connectivity inspection. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     The present invention is described hereinafter. The terms used herein should be understood as being used in the meaning that is commonly used in the art, unless specifically noted otherwise. Thus, unless defined otherwise, all terminologies and scientific technical terms that are used herein have the same meaning as the general understanding of those skilled in the art to which the present invention pertains. In case of a contradiction, the present specification (including the definitions) takes precedence. 
     As used herein, “about” refers to a range of ±10% from the number that is described subsequent to “about”. 
     The problem to be solved by the present invention is to provide an aerial vehicle that enables safe and simple electrical connectivity inspection on a structure. The problem to be solved described above was solved by providing An aerial vehicle, comprising: 
     an aerial vehicle body; 
     a conductive member for contacting a conductor of a structure; and 
     a moving mechanism capable of moving the conductive member between a distal position and a proximal position of the aerial vehicle body. 
     Specifically, the conductive member for contacting a conductor of a structure can move between the distal position and the proximal position of the aerial vehicle body in view of the moving mechanism in the aerial vehicle of the invention. Thus, electrical connectivity can be inspected by moving the aerial vehicle to a position below the conductor of the structure while the conductive member is at the proximal position and subsequently moving the conductive member from the proximal position to the distal position to contact the conductive member with the conductor of the structure. 
     For this reason, a conductive member of an aerial vehicle and a conductor of a structure can be contacted at least by an operation of moving the conductive member from the proximal position to the distal position of the aerial vehicle body, where there is hardly any risk of the aerial vehicle body colliding with the structure, so that the conductive member of the aerial vehicle and the conductor of the structure can be contacted safely and easily. 
     Thus, if the aerial vehicle of the invention has a conductive member for contacting a conductor of a structure and a moving mechanism capable of moving the conductive member between a distal position and a proximal position of an aerial vehicle body, the specific configuration of the conductive member and the moving mechanism and other configurations in the aerial vehicle are not particularly limited and can have any configuration. 
     Aerial Vehicle Body 
     An aerial vehicle body can be of any form. For example, an aerial vehicle body may be a helicopter or a multicopter such as a drone. An aerial vehicle body may be a manned or unmanned aerial vehicle. In a preferred embodiment, an aerial vehicle body is an unmanned aerial vehicle such as a remotely controllable drone. Electrical connectivity can be safely inspected by configuring an aerial vehicle as an unmanned aerial vehicle. 
     Conductive Member 
     As long as a conductive member is a member having conductivity for contacting a conductor of a structure, other parts of the member can have any configuration. 
     For example, the material of a conductive member is not limited to metal, as long as the material has conductivity. The material may be carbon or plastic. Furthermore, a specific member comprises at least one of metal wire netting, checker plate, acicular metal (metal scrubber or metal brush), conductive rubber, conductive sponge, conductive wire (electric wire, conductive fiber, or conductive spring), conductive grease, conductive oil, polishing member, and perforated board. 
     A conductive member can have any shape or size in accordance with the shape or size of a conductor of a structure to be contacted. For example, the shape of a surface to be contacted with a conductor of a structure of a conductive member may be substantially polygonal (triangular, quadrangular, pentagonal, etc.) or substantially circular (circular, oval, etc.). While a conductive member is preferably large from the viewpoint of increasing the area of contact with a conductor of a structure, a large area would be heavier and is affected by wind, so that flight would be unstable. Thus, the area can be determined while considering the balance thereof. In an embodiment where a conductor of a structure is for example a receptor of a wind turbine blade, the size of the surface to be contacted with the receptor of a conductive member is about 70 cm 2  to about 2500 cm 2 . In one embodiment, the conductive member is substantially circular with an area of about 700 cm 2  (diameter of about 30 cm). However, the present invention is not limited thereof. 
     A conductive member may comprise fixing means for fixation to a conductor of a structure. Fixing means can have any configuration. For example, fixing means may be a magnetic force generating mechanism that causes fixation to a conductor by a magnetic force, a conductive adhesive tape, etc., or fixation by adhesion through air suction means. 
     Moving Mechanism 
     A moving mechanism can have any form, as long as it is capable of moving a conductive member between a distal position and a proximal position of an aerial vehicle body. 
     For example, a moving mechanism may comprise a support rod for supporting a conductive member and rod moving means capable of moving the support rod to a distal direction. Alternatively, a moving mechanism may comprise an extendable/retractable support rod for supporting a conductive member and rod extending/retracting means for extending/retracting the support rod. In this regard, the extendable/retractable support rod may comprise at least a first rod coupled to a conductive member and a second rod for protrudably and embeddably housing the first rod. Specifically, a moving mechanism may be configured so that a support rod extends by a first rod protruding out with respect to a second rod, and the support rod contracts by the first rod being embedded with respect to the second rod. The distance of movement between a distal position and a proximal position of a conductive member due to a moving mechanism can be any distance. For example, the distance of movement between a distal position and a proximal position is about 30 cm to about 150 cm. The direction of movement of a conductive member due to a moving mechanism can be any direction. For example, the direction of movement of a conductive member may be in a substantially vertical direction or a substantially horizontal direction of an aerial vehicle body. Preferably, a moving mechanism moves a conductive member in a substantially vertical direction of an aerial vehicle body. Since an aerial vehicle such as a drone can more readily move in a substantially vertical direction relative to a substantially horizontal direction, a conductive member can contact a conductor of a structure more readily if a moving mechanism can move the conductive member in a substantially vertical direction of an aerial vehicle body. When a moving mechanism moves a conductive member in a substantially vertical direction of an aerial vehicle body, it is possible to avoid the aerial vehicle body from colliding with a structure even if the aerial vehicle body is shaken in a substantially horizontal direction by a side wind. 
     When a moving mechanism moves a conductive member in a substantially vertical direction of an aerial vehicle body, a distal position may be a position in an upward direction or downward direction of the substantially vertical direction with respect to a proximal position. When an aerial vehicle body is remotely controlled, etc., it is easier for the visual recognition of an operator to have the aerial vehicle body approach a structure from below as a method of having the aerial vehicle body approach a conductor of the structure. In such a case, it is preferable that the moving mechanism moves the conductive member in a substantially vertical direction of the aerial vehicle body, and the distal position is a position in an upward direction of the substantially vertical direction with respect to the proximal position. However, the present invention is not limited thereto. 
     A support rod may further comprise fixing means for fixing a conductive member to a conductor. Fixing means can have any configuration. Fixing means may be, for example, a clamp comprising a linking mechanism, or fixation by adhesion through air suction means. 
     A support rod can also be detachable to an aerial vehicle. This is configured so that detachment/attachment from/to an aerial vehicle can be operated based on a wireless or wired instruction signal. 
     Other Configurations 
     Furthermore, the connecting structure between a conductive member and a support rod can have any form. For example, a conductive member and a support rod may be coupled with a coupling member so that a posture of the conductive member with respect to the support rod (rotation direction or rotation angle with respect to the support rod) is fixed, or a conductive member and a support rod may be coupled with a coupling member so that a posture of the conductive member with respect to the support rod (rotation direction or rotation angle with respect to the support rod) can be changed in any manner. 
     A coupling member for coupling a conductive member and a support rod so that a posture of the conductive member with respect to the support rod can be changed in any manner may be, for example, a universal joint such as a ball joint, or may comprise a plurality of flexible members, which are disposed with a given angular interval axially about the support rod. In this regard, the flexible members can have any form. For example, flexible members may be a spring member such as a leaf spring or coil spring, an elastic wire (made of metal, resin, etc.), rubber support column or air tube, electric or air cylinder, sponge, support column comprising a parallel link mechanism, etc. 
     A coupling member can have any number of flexible members greater than one, such as two, three, or four or more. The orientation of the posture can be changed in various directions by increasing the number of flexible members. Flexible members can be disposed axially about a support rod at any angular interval. In a preferred embodiment, the angles at which a plurality of flexible members are disposed axially about a support rod are equal. By equally disposing a plurality of flexible members axially about a support rod in this manner, the posture of a conductive member can be changed nearly equally in directions in accordance with the orientation of the angle of force, regardless of the orientation of the angle of force applied to a conductive member. As a result, when moving a conductive member from below to above so that the conductive member abuts a wind turbine blade by moving a support rod, the conductive member can maintain a state of abutting the wind turbine blade by changing a posture of the conductive member in a direction in accordance with the orientation of a force, even when an aerial vehicle body moves sideways, etc. from being subjected to a force such as a side wind. In one embodiment, there are four flexible members each disposed at an interval of about 90° axially about a support rod. However, the present invention is not limited thereto. Adjacent flexible members may be disposed at different angles from one another. In a preferred embodiment, a configuration wherein a rotation (displacement) to any direction to which a force is applied can be readily achieved, much like a configuration with a ball joint or a plurality of flexible members disposed at a given angular interval axially about a support rod is employed. Furthermore, a force restoring the original posture can be exerted, even if the posture of a conductive member has changed due to application of an external force, by constructing a plurality of flexible members with an elastic wire or spring member. As a result, the posture of a conductive member can be stably maintained in a more efficient manner than a universal joint such as a ball joint. 
     Furthermore, an aerial vehicle may comprise a rotation mechanism for rotating a conductive member. 
     In this regard, the specific configuration of a rotation mechanism can be any configuration. For example, a rotation mechanism may be a structure, which can house a rotation shaft rotatably inside a support rod, supports a conductive member at one end of the rotation shaft housed in the support rod, and is connected to a rotation axis of a motor at the other end of a rotation shaft, or may be a rod rotation means for rotating the support rod, which rotatably retains rod moving means for causing ascent and descent of the support rod and has a built-in motor for rotating the support rod by the entire rod moving means, or may be a structure with a rotation mechanism provided to a coupling member for coupling the support rod and the conductive member, or may be a structure comprising a rotation mechanism in the conductive member itself. Insulating coating, waste, rust, etc. adhering to the surface of a conductor (receptor) can be removed by contacting the rotated conductive member with the conductor (receptor). The rotation speed, etc. of a conductive member can be appropriately adjusted in accordance with the material of the conductive member or status of an object to be removed. 
     The problem to be solved by the present invention is to provide a method that enables safe and simple electrical connectivity inspection on a conductor of a structure. The problem to be solved described above was solved by providing: 
     A method of conducting electrical connectivity inspection on a structure by using the aerial vehicle described above, comprising: 
     moving the aerial vehicle to a position below a conductor of the structure while the conductive member is at a proximal position; and 
     contacting the conductive member with a conductor of the structure by moving the conductive member to a distal position to conduct electrical connectivity inspection. 
     Furthermore, a structure and a conductor thereof in the present invention are not particularly limited and can have any configuration. For example, a structure is a tall structure such as a steel pole of a power line, high-rise building, or a wind turbine. A conductor of a structure is, for example, a lightning rod provided at the top end of a steel pole of a power line or on the roof of a high-rise building, and particularly preferably a receptor provided at the tip of a wind turbine blade of a wind turbine. 
     However, the following Embodiments 1 and 2 disclose moving mechanisms comprising a support rod for supporting a conductive member and rod moving means capable of moving the support rod to a distal direction. Embodiment 1 discloses those with the posture of a conductive member fixed with respect to a support rod. 
     Instead of the moving mechanism in Embodiment 1, Modified Example 1 of Embodiment 1 discloses a moving mechanism comprising an extendable/retractable support rod for supporting a conductive member and rod extending/retracting means for extending/retracting a support rod. 
     Modified Example 2 of Embodiment 1 discloses an aerial vehicle comprising a rotation mechanism for rotating a conductive member, in addition to the configuration of Embodiment 1. In particular, Modified Example 2 of Embodiment 1 discloses a rotation mechanism, which supports a conductive member at one end of a rotation shaft and is connected to a rotation axis of a motor at the other end of the rotation shaft. 
     Instead of the configuration of Embodiment 1 wherein the posture of a conductive member with respect to a support rod is fixed, Embodiment 2 discloses a configuration wherein the posture of a conductive member with respect to a support rod can be changed in any manner. In particular, Embodiment 2 discloses a configuration comprising a plurality of flexible members as a coupling member, which couples a conductive member to a support rod in a manner that the posture thereof can be changed in any manner. 
     The embodiments of the invention are described hereinafter with reference to the drawings. 
     Embodiment 1 
       FIG.  1    is a perspective view for describing aerial vehicle  100  according to Embodiment 1 of the invention.  FIG.  1 ( a )  shows the outer appearance of the aerial vehicle  100 , and  FIG.  1 ( b )  shows a state in which conductive member  120  is separated from the aerial vehicle  100 . 
     As shown in  FIG.  1 ( a ) , the aerial vehicle  100  of Embodiment 1 comprises an aerial vehicle body  110 ; a conductive member  120 , which is a tentacle, for contacting a conductor of a structure; and a moving mechanism  130  capable of moving the conductive member  120  between a distal position and a proximal position of the aerial vehicle body  110 . 
     Aerial Vehicle Body  110   
     As shown in  FIG.  1 ( b ) , the aerial vehicle body  110  is an airframe having a housing  110   b,  four thrust generation units  110   a,  four support arms  110   d  for supporting the four thrust generation units  110   a  to the housing  110   b,  and legs  110   c  attached to the housing  110   b,  wherein each thrust generation unit  110   a  has a propeller  111  and a driving motor  112 . The base portion of each of the support arms  110   d  is fixed to the housing  110   b.  The driving motors  112  are attached to the tip of the respective support arms  110   d , and the propellers  111  are attached to a rotation axis of the respective driving motors  112 . 
     The housing  110   b  is equipped with a controller  10   a  and a battery  10   b.  The battery  10   b  is a power source for driving the driving motor  112  as well as a power source for a driving unit (not shown) of the moving mechanism  130 . The controller  10   a  comprises a wireless communication unit and is a control unit for controlling flight of the aerial vehicle  100  by receiving an operation signal from a wireless remote controller and controlling the number of rotations of the four driving motors  112 . The control unit also controls the driving unit (not shown) of the moving mechanism  130  to control the movement of the conductive member  120 . 
     The embodiment shown in the diagram is described as comprising four thrust generation units and support arms, but the present invention is not limited thereto. The aerial vehicle body may have any number of thrust generation units and support arms, such as four or less (e.g., 2, etc.) or 5 or more (e.g., 8, etc.). 
     Conductive Member  120   
     The conductive member  120  is electrically connected to a measurement device on the ground through a measurement cable (not shown). In this regard, the conductive member is comprised of metal wire netting for achieving a light weight. However, the conductive member  120  is not limited to those comprised of metal wire netting, and may be comprised of a checker plate, a metal scrubber, a perforated board, or other metal member. 
     Moving Mechanism  130   
     As shown in  FIG.  1 ( b ) , the moving mechanism  130  is built into the housing  110   b  of the aerial vehicle body  110  and has a support rod  130   a  for supporting the conductive member  120 , and rod moving means  130   b  capable of moving the support rod  130   a  to a distal direction (upward direction of the housing  110   b ). The conductive member  120  and the support rod  130   a  are coupled with a coupling member  130   c  so that the posture of the conductive member  120  with respect to the support rod  130   a  is fixed in the moving mechanism  130 . The coupling member  130   c  is a metal tubular member mated with the tip of the support rod  130   a.  A metal wire netting member is fixed to the top surface of the tubular member as the conductive member  120  by a fastening screw, brazing, welding, adhesive, etc. The coupling member  130   c  does not need to be a metal tubular member. As long as the conductive member  120  can be coupled to the support rod  130   a,  a resin member may be used, or a solid member may be used instead of a tubular member. 
     The moving mechanism  130  is described hereinafter in detail. 
       FIG.  2    is a diagram for describing the specific configuration of the moving mechanism  130  of the aerial vehicle  100  shown in  FIG.  1   .  FIG.  2 ( a )  is a side view of the aerial vehicle  100  in  FIG.  1    viewed from direction A, and  FIG.  2 ( b )  is a vertical cross-sectional view of the housing  110   b  shown in  FIG.  2 ( a )  and shows the specific configuration of the rod moving means  130   b  housed inside the housing  110   b.  In  FIG.  2   , the propeller  111 , the driving motor  112 , and the near side support arm  110   d  are omitted in  FIG.  2    to simplify the drawing. 
     The support rod  130   a  of the moving mechanism  130  is attached, to the housing  110   b,  slidably in a substantially vertical direction of the aerial vehicle body  110  and penetrates through the housing  110   b.  The rod moving means  130   b  of the moving mechanism  130  has a pair of rollers  31   a  and  31   b  and respective roller bearings  32   a  and  32   b.    
     In this regard, the pair of rollers  31   a  and  31   b  are disposed within the housing  110   b  to oppose each other while flanking the support rod  130   a.  The rollers  31   a  and  31   b  are rotatably supported by the respective roller bearings  32   a  and  32   b  attached to the inside of the housing  110   b.    
     The rod moving means  130   b  is configured so that the support rod  130   a  flanked by the rollers  31   a  and  31   b  moves up and down along a substantially vertical direction by rotating the pair of rollers  31   a  and  31   b  in one direction or the reverse direction. In this regard, driving means of the rollers  31   a  and  31   b  may be a motor provided external to the rollers  31   a  and  31   b,  but driving means of the rollers  31   a  and  31   b  are preferably a motor built into the rollers  31   a  and  31   b  from the viewpoint of arrangement space. The motors that are driving means of the rollers  31   a  and  31   b  are configured to be supplied with power from the battery  10   b  and controlled by the controller  10   a.    
     The rod moving means  130   b  may use a pinion (round gear) instead of the pair of rollers  31   a  and  31   b.  In such a case, it is necessary to install a rack (with teeth engaging the teeth of the pinion formed on an elongated and flat board member) that engages with the pinion on the support rod  130   a.    
     As the constituent material of the housing  110   b , support arm  110   d,  leg  110   c,  and propeller  111  constituting the aerial vehicle body  110 , the support rod  130   a  and coupling member  130   c,  and the rollers  31   a  and  31   b  and roller bearings  32   a  and  32   b  constituting the rod moving means  130   b,  a metal material such as steel, aluminum, stainless steel, or titanium may be used, or a hard resin material such as PVC (polyvinyl chloride), PS (polystyrene), ABS (acrylonitrile butadiene styrene), PMMA (polymethylmethacrylate), etc. may be used, or a metal material may be used for some members, and resin material for some other members. 
     A method of inspecting electrical connectivity of a receptor of a wind turbine blade, etc. by using the aerial vehicle  100  with such a configuration is now described. 
       FIG.  3    is a diagram for describing a method of inspecting electrical connectivity of a receptor, etc. by using the aerial vehicle  100  shown in  FIG.  1   .  FIG.  3 ( a )  shows ascending and descending motions of the aerial vehicle  100  in  FIG.  1   , and  FIG.  3 ( b )  shows an upward movement of the conductive member  120  of the aerial vehicle  100  in  FIG.  1   . 
     A method of conducting electrical connectivity inspection on a structure such as a wind turbine blade of a wind turbine by using the aerial vehicle  100  shown in  FIG.  1    comprises at least the following first step and second step. 
     First Step 
     The first step is a step for moving the aerial vehicle  100  to a position below a conductor of a structure while maintaining the conductive member  120  at a proximal position with respect to the aerial vehicle body  110 . 
     Specifically, a conductor of a structure is a receptor Lc of a wind turbine blade Wb, and the aerial vehicle  100  is operated with a wireless remote controller. The controller  10   a  of the aerial vehicle  100  controls the thrust (number of rotations of the driving motor  112 ) at the four thrust generation units  110   a  in accordance with an operation signal from the wireless remote controller (not shown), and controls the ascent/descent of the support rod  130   a  using the pair of rollers  31   a  and  31   b  of the rod moving means  130   b  in accordance with an operation signal, whereby flight of the aerial vehicle  100  and movement of the conductive member  120  are controlled as intended by an operator. 
     In the first step, the aerial vehicle  100  leaves ground surface Gr while stably maintaining the conductive member  120  at a position closest to the housing  110   b  of the aerial vehicle  100  (proximal position with respect to the aerial vehicle body  110 ) by an operation of an operator, and flies to a position in the vicinity of the lower side of the receptor Lc, which is positioned at the bottom end of the wind turbine blade Wb (see  FIG.  3 ( a ) ). Preferably, the aerial vehicle  100  is floated at a position in the vicinity of the lower side (hovering). 
     In this regard, the proximal position of a conductive member is a position of the conductive member  120  where the distance between a receptor contact surface of the conductive member  120  and the top surface of the housing  110   b  is about 0 cm to about 70 cm in the aerial vehicle  100 . The position in the vicinity of the lower side of the receptor Lc is a position of the aerial vehicle  100  where the distance between the receptor contact surface of the conductive member  120  in the proximal position and the bottom end of the receptor Lc is about  150  cm or less. 
     Second Step 
     The second step is a step for contacting the conductive member  120  with a conductor of a structure by moving the conductive member  120  to a distal position with respect to the aerial vehicle body  110  to conduct electrical connectivity inspection. 
     Specifically, in the second step, the conductive member  120  is moved to the distal position with respect to the aerial vehicle  110  from the proximal position with respect to the aerial vehicle body  110  while the aerial vehicle  100  is floated at a position in the vicinity of the lower side of the receptor Lc (see  FIG.  3 ( b ) ). 
     In this regard, the distal position is a position of the conductive member  120  where the distance between the bottom surface of the conductive member and the top surface of the housing  110   b  is about 30 cm to about 150 cm. 
     Thus, in the aerial vehicle  100  floating at a position in the vicinity of the lower side of the receptor Lc, the conductive member  120  abuts the receptor Lc of the wind turbine blade Wb while moving from the proximal position to the distal position to electrically connect the conductive member  120  of the aerial vehicle  100  with the receptor Lc of the wind turbine blade Wb, whereby the receptor Lc of the wind turbine blade Wb is connected to a measurement device on the ground via the conductive member  120  of the aerial vehicle  100  and measurement cable (not shown), and the quality of electrical connection via a down conductor between the receptor and the ground is determined in the measurement device on the ground. 
     When moving the conductive member  120  from the proximal position with respect to the aerial vehicle body  110  to the distal position with respect to the aerial vehicle body  110  in the second step, the aerial vehicle  100  may be elevated towards the receptor Lc instead of maintaining the aerial vehicle  100  in a floated state at a position in the vicinity of the lower side of the receptor Lc. After inspecting electrical connectivity by contacting the conductive member  120  with the receptor Lc, the aerial vehicle  100  is descended and landed on the ground surface Gr while the conductive member  120  is returned to the proximal position with respect to the aerial vehicle body  110  and the aerial vehicle  100  is stabilized (see  FIG.  3 ( a ) ). 
     Since the aerial vehicle  100  in Embodiment 1 comprises the aerial vehicle body  110 , the conductive member  120  for contacting a conductor of a structure, and the moving mechanism  130  capable of moving the conductive member  120  between a distal position and a proximal position of the aerial vehicle body  110  as described above, manual labor at a high elevation is not required. Thus, electrical connectivity can be inspected safely. Even if the aerial vehicle body  110  is shaken due to an effect of a side wind etc., the possibility of collision of the aerial vehicle body  110  with the structure (wind turbine blade) Wb can be averted by configuring the conductive member  120  to be contacted with the receptor Lc while the conductive member  120  is disposed at a distal position away from the aerial vehicle body by the moving mechanism. For this reason, the aerial vehicle  100  of the invention enables safe and simple electrical connectivity inspection on the conductor Lc of the wind turbine blade Wb. 
     The embodiment shown in  FIG.  3    describes a case where the aerial vehicle  100  is elevated from below the receptor Lc to contact the conductive member  120  with the receptor Lc, but the present invention is not limited thereto. The aerial vehicle  100  may be descended from above the receptor Lc to contact the conductive member  120  with the receptor Lc, or the aerial vehicle  100  may be moved substantially horizontally from the side of the receptor Lc to contact the conductive member  120  with the receptor Lc. In a preferred embodiment, the aerial vehicle  100  is elevated from below the receptor Lc to contact the conductive member  120  with the receptor Lc. With such a configuration, the risk of collision with the wind turbine blade Wb can be reduced even if the aerial vehicle  100  is shaken due to a side wind, etc. Since an aerial vehicle such as a drone or helicopter can be maintained more stably when the aerial vehicle  100  is moved up or down rather than substantially horizontally in view of the mechanism thereof, the aerial vehicle  100  can be contacted with the receptor Lc more stably when moved up and down rather than substantially horizontally. 
     The moving mechanism  130  in the aerial vehicle  100  of Embodiment 1 comprises the support rod  130   a  for supporting the conductive member  120  and the rod moving means  130   b  capable of moving the support rod  130   a  in a distal direction, but the specific configuration of the moving mechanism  130  is not limited to the configuration of Embodiment 1. The support rod itself may have an extendable/retractable structure. The aerial vehicle  101  comprising a moving mechanism  131  with such a configuration is described hereinafter as Modified Example 1 of Embodiment 1. 
     Modified Example 1 of Embodiment 1 
       FIG.  4    is a diagram for describing the moving mechanism  131  of an aerial vehicle  101  according to Modified Example 1 of Embodiment 1.  FIG.  4 ( a )  is a side view of the aerial vehicle  101 , and  FIG.  4 ( b )  is a vertical cross-sectional view of the housing  110   b  shown in  FIG.  4 ( a ) . Specific configurations of the support rod  131   a  and the rod extending/retracting means  131   b  attached thereto are shown. The propeller  111 , the driving motor  112 , and the near side support arm  110   d  are omitted in  FIG.  4   , just like  FIG.  2   , to simplify the drawing. 
     The aerial vehicle  101  of Modified Example 1 of Embodiment 1 comprises the moving mechanism  131 , which has a different configuration from the moving mechanism  130  in Embodiment 1. The moving mechanism  131  comprises an extendable/retractable support rod  131   a  in place of the support rod  130   a  in the moving mechanism  130 , and rod extending/retracting means  131   b  for extending/retracting the support rod  131   a  in place of the rod moving means  130   b  for moving the support rod  130   a.    
     Thus, other configurations in the aerial vehicle  101  in Embodiment 1, i.e., configurations other than the support rod  131   a  and the rod extending/retracting means  131   b,  are identical to those in the aerial vehicle  100  of Embodiment 1. 
     In this regard, the extendable/retractable support rod  131   a  comprises a first rod  31   a   1  coupled to the conductive member  120 , a second rod  31   a   2  for protrudably and embeddably housing the first rod  31   a   1 , and a third rod  31   a   3  for protrudably and embeddably housing the second rod  31   a   2 . The first rod  31   a   1  is comprised of a stick-like member, and the second rod  31   a   2  and the third rod  31   a   3  are comprised of a tubular member. The metal material or hard resin material disclosed as a constituent material of the aerial vehicle  100  in Embodiment 1 can be used as the material of a stick-like member and tubular member. 
     The rod extending/retracting means  131   b  has a housing  3   a,  a wire member  3   d,  a driving roller  3   b,  and a guide roller  3   c.  The material of these members may be the metal material or resin material described above. However, the wire member  3   d  is flexible to the extent that the wire member can be reeled in by the main roller  3   b  and is rigid to the extent that the conductive member  120  can be pushed up with the first rod  31   a   1  and the second rod  31   a   2 . A motor is built into the driving roller  3   b.  However, a motor for rotating the driving roller  3   b  may be provided externally instead of being built into the driving roller  3   b.  The motor is operated with the battery  10   b  and controlled by the controller  10   a.    
     In this regard, the housing  3   a  of the rod extending/retracting means  131   b  is attached to the bottom end of the third rod  31   a   3 , and the driving roller  3   b  and the guide roller  3   c  are disposed inside the housing  3   a.  The wire member  3   d  is wrapped onto the driving roller  3   b,  and the tip of the wire member  3   d  is coupled to the bottom end of the first rod  31   a   1 . The guide roller  3   c  is disposed in the vicinity of the driving roller  3   b  to guide the wire member  3   d  so that the wire member  3   d  reeled out from the driving roller  3   b  extends along a vertical direction. 
     In the support rod  131   a  with such a configuration, the first rod  31   a   1  is pushed by the wire member  3   d  and protrudes out from within the second rod  31   a   2  when the wire member  3   d  is reeled out by a rotation of the driving roller  3   b.  However, once the bottom end of the first rod  31   a   1  approaches the top end of the second rod  31   a   2  to within a certain distance, ascent of the first rod  31   a   1  with respect to the second rod  31   a   2  stops, and the first rod  31   a   1  together with the second rod  31   a   2  ascend with respect to the third rod  31   a   3 . Once the bottom end of the second rod  31   a   2  approaches the top end of the third rod  31   a   3  to within a certain distance, the ascent of the second rod  31   a   2  with respect to the third rod  31   a   3  is configured to stop. The support rod  131   a  is thereby configured to extend/retract like a multi-segmented antenna without the first rod  31   a   1  falling out of the second rod  31   a   2  or the second rod  31   a   2  falling out of the third rod  31   a   3  when the support rod  131   a  is extended. In the embodiment shown in  FIG.  4   , the support rod is comprised of first to third rods, but the present invention is not limited thereto. A support rod may be comprised of first and second rods or four or more rods. 
     Since the support rod  131   a  itself is fixed without moving with respect to the aerial vehicle body in such a moving mechanism  131  comprising the support rod  131   a  and rod extending/retracting means  131   b,  interference with other configurations of a device is suppressed. Thus, the moving mechanism can have a simple configuration. 
     The aerial vehicle  100  in Embodiment 1 and the aerial vehicle  101  in Modified Example 1 thereof described above may comprise a rotation mechanism for rotating the conductive member  120  in addition to the configurations described above. In the following Modification Examples 2 and 3, the aerial vehicle  100  in Embodiment 1 comprising a rotation mechanism for rotating the conductive member  120  (aerial vehicles  102  and  103 ) is described. 
     Modification Example 2 of Embodiment 1 
       FIG.  5    is a diagram for describing a rotation mechanism for rotating the conductive member  120  of aerial vehicle  102  according to Modified Example 2 of Embodiment 1.  FIG.  5 ( a )  is a side view of the aerial vehicle  102 , and  FIG.  5 ( b )  is a vertical cross-sectional view of the housing  110   b  shown in  FIG.  5 ( a ) . A specific configuration of a rotation mechanism  132   d  for rotating a conductive member is disclosed. 
     The aerial vehicle  102  according to Modification Example 2 of Embodiment 1 comprises a support rod  132   a  comprising a rotation shaft  2   a   2  and a rotation motor  32   d  for rotating the rotation shaft  2   a   2  in place of the support rod  130   a  of the aerial vehicle  100  in Embodiment 1. The rotation mechanism  132   d  for rotating the conductive member  120  is comprised of the support rod  132   a  and the rotation motor  32   d  by supporting the conductive member  120  substantially at the tip of the rotation shaft  2   a   2 . The other configurations are identical to those in the aerial vehicle  100  in Embodiment 1. 
     Specifically, the support rod  132   a  has a tubular support rod body  2   a   1  and a stick-like rotation shaft  2   a   2  housed within the support rod body  2   a   1 . The rotation shaft  2   a   2  is rotatably retained within the support rod body  2   a   1 . The top end of the rotation shaft  2   a   2  protrudes out from the support rod body  2   a   1  and is coupled to the conductive member  120  with the coupling member  130   c.    
     The bottom end of the support rod body  2   a   1  is attached to the rotation motor  32   d.  The rotation axis of the rotation motor  32   d  is coupled to the bottom end of the stick-like rotation shaft  2   a   2  housed within the support rod body  2   a   1 . The rotation motor  32   d  is shaft rotation means for rotating the rotation shaft  2   a   2 . 
     Thus, in Modification Example 2 of Embodiment 1, the rotation mechanism  132   d  for rotating the conductive member  120  is comprised of the support rod  132   a  and the shaft rotation means  132   d.    
     Since the moving mechanism  132  in the aerial vehicle  102  according to Modification Example 2 of Embodiment 1 with such a configuration comprises the rotation mechanism  132   d  for rotating the conductive member  120  in addition to the rod moving means  130   b  capable of moving the support rod  132   a  in a distal direction, the conductive member  120  can be contacted with the receptor Lc of the wind turbine blade Wb in a state where the conductive member  120  is rotated. Rotating a conductive member in such a manner can remove any insulating coating, waste, or rust adhering to the surface of the receptor Lc of the wind turbine blade Wb by the rotating conductive member  120 , and can further ensure inspection of electrical connection via a down conductor of the conductive member  120  and the receptor Lc of the wind turbine blade Wb. 
     Modification Example 2 of Embodiment 1 discloses the rotation mechanism  132   d  for rotating the conductive member  120 , wherein the conductive member  120  is coupled to one end of the rotation shaft  2   a   2  rotatably housed inside the support rod body  2   a   1 , and a rotation axis of the rotation motor  32   d  is coupled to the other end of the rotation shaft  2   a   2 , but the configuration of the rotation mechanism  132   d  of the invention is not limited thereto. For example, the configuration may rotate the rod moving means  130   b  of Embodiment 1, or may comprise a rotation mechanism in the conductive member  120  itself. 
     Furthermore, Embodiment 1 and Modification Examples 1 and 2 thereof disclose the aerial vehicles  100  to  103  wherein the posture of the conductive member  120  with respect to a support rod is fixed, but aerial vehicles are not limited to those in which the posture of a conductive member with respect to a support rod is fixed. An aerial vehicle may be an aerial vehicle wherein the posture of a conductive member with respect to a support rod (rotation direction or rotation angle with respect to the support rod) can be changed in any manner. An aerial vehicle with such a configuration is described hereinafter as Embodiment 2. 
     Embodiment 2 
       FIG.  6    is a perspective view for describing aerial vehicle  200  according to Embodiment 2 of the invention.  FIG.  6 ( a )  shows the outer appearance of the aerial vehicle  200 , and  FIG.  6 ( b )  shows the structure of coupling member  230   c  by separating the conductive member  120  from the aerial vehicle  200 . 
     The aerial vehicle  200  of Embodiment 2 is different only in terms of the following: the coupling member  130   c  of the aerial vehicle  100  of Embodiment 1 is coupled so that the posture of the conductive member  120  with respect to the moving mechanism  130  is fixed, whereas the coupling member  230   c  is coupled so that the posture of the conductive member  120  with respect to the moving mechanism  230  can be changed in any manner. 
     Specifically, the coupling member  230   c  comprises a plurality of flexible members  23  consisting of an elastic metal wire, and the plurality of flexible members  23  are disposed with a given angular interval axially about the support rod  130   a.  In this regard, the four flexible members  23  are disposed axially about the support rod  130   a  at an angular interval of 90°. However, the four flexible members  23  are not limited to a metal wire member and may be a coil spring, leaf spring, or elastic resin or rubber, as long as they can support the conductive member  120  at a given posture (e.g., horizontally) and deform when the conductive member  120  abuts a receptor of a wind turbine blade. 
     A method of inspecting electrical connectivity of a receptor of a wind turbine blade, etc. by using the aerial vehicle  200  with such a configuration is now described. 
       FIG.  7    is a diagram for describing a method of inspecting electrical connectivity of a receptor, etc. by using the aerial vehicle  200  shown in  FIG.  6   .  FIG.  7 ( a )  shows the ascending and descending motions of the aerial vehicle  200  in  FIG.  7   , and  FIG.  7 ( b )  shows an upward movement of the conductive member  120  of the aerial vehicle  200  in  FIG.  6   . 
     Electric connectivity inspection on a structure such as a wind turbine blade of a wind turbine by using the aerial vehicle  200  of Embodiment 2 is also conducted in the same manner as the electric connectivity inspection using the aerial vehicle  100  of Embodiment 1. 
     Specifically, as shown in  FIG.  7 ( a ) , the aerial vehicle  200  is moved to a position below the conductor Lc of the wind turbine blade Wb while maintaining the conductive member  120  at a proximal position with respect to the aerial vehicle body  110  (first step). 
     Next, as shown in  FIG.  7 ( b ) , the conductive member  120  is contacted with the conductor Lc of the structure Wb by moving the conductive member  120  to a distal position with respect to the aerial vehicle body  110  to conduct electric connectivity inspection (second step). 
     The aerial vehicle  200  can avoid losing the balance while maintaining the contact of a conductive member with the conductor Lc by changing the posture of the conductive member  120  with respect to the support rod  131   a  (rotation direction or rotation angle with respect to the support rod) in accordance with the force of wind as shown in  FIG.  7 ( b ) , even if a point of contact where the conductive member  120  contacts the conductor Lc of the structure Wb becomes offset from the center of the aerial vehicle  100  due to a force of a wind, etc. in the aerial vehicle  200  of Embodiment 2. 
     Subsequently, the aerial vehicle  200  is descended and landed on the group surface Gr while the conductive member  120  is returned to the proximal position with respect to the aerial vehicle body  110  and the aerial vehicle  200  is stabilized, in the same manner as the electric connectivity inspection using the aerial vehicle  100  of Embodiment 1 (see  FIG.  7 ( a ) ). 
     In the aerial vehicle  200  of Embodiment 2 with such a configuration, the conductive member  120  is coupled to the support rod  130   a  in a manner that the posture (rotation direction or rotation angle with respect to the support rod) can be changed with the coupling member  230   c  comprising the plurality of flexible members  23  in addition to the configuration of the aerial vehicle  100  of Embodiment 1. Thus, the aerial vehicle  200  can avoid losing balance while maintaining the contact of the conductive member  120  with a receptor by changing the posture of the conductive member  120  in accordance with a force of a wind, etc. when the conductive  120  abuts a receptor of a wind turbine blade at a position offset from the center of the aerial vehicle  200  due to the force, in addition to the effect of the aerial vehicle  100  of Embodiment 1. 
     While the coupling member  230   c  having a plurality of flexible members  23  was used in the aerial vehicle  200  of Embodiment 2, a coupling member is not limited to those with such a structure. For example, a universal joint or a ball joint may be used as a coupling member. 
     Embodiment 3 
     A method of inspecting electric connectivity of a receptor of a wind turbine blade, etc. by using the aerial vehicle  300  of Embodiment 3 is now described. 
       FIG.  8 A  is a diagram for describing a method of inspecting electrical connectivity of a receptor, etc. by using aerial vehicle  300  according to Embodiment 3 of the invention.  FIG.  8 A (a) shows ascending and descending motions of the aerial vehicle  300 , and  FIG.  8 A (b) shows an operation of fixing the conductive member  120  of the aerial vehicle  300  to a receptor.  FIG.  8 B (a) shows an operation of releasing the aerial vehicle  300  from a wind turbine blade while a conductive member is still fixed to a receptor, and  FIG.  8 B (b) shows an operation of disengaging fixation of a conductive member to a receptor and releasing the conductive member and a support rod from a wind turbine blade after electrical connectivity inspection. 
     A method of conducting electric connectivity inspection on a structure such as a wind turbine blade of a wind turbine by using the aerial vehicle  300  shown in  FIG.  8 A  comprises at least the following first to fourth steps. 
     First Step 
     The first step is the same as the first step for the aerial vehicle  100  of Embodiment 1 shown in  FIG.  3   . 
     Second Step 
     The second step is the same as the second step for the aerial vehicle  100  of Embodiment 1 shown in  FIG.  3   , until the aerial vehicle  300  floating at a position in the vicinity of the lower side of the receptor Lc abuts the receptor Lc of the wind turbine blade Wb during the move of the conductive member  120  from a proximal position to a distal position. 
     Third Step 
     As shown in  FIG.  8 A (b), the conductive member  120  is fixed to the receptor Lc by attaching the support rod  130   a  to the wind turbine blade Wb through actuation of a clamp (fixing means)  150  comprising a linking mechanism equipped by the support rod  130   a  while the conductive member  120  abuts the receptor Lc of the wind turbine blade Wb. 
     Fourth Step 
     As shown in  FIG.  8 B (c), the conductive member  120  is fixed to the receptor Lc by the fixing means  150 , and then the aerial vehicle  300  is released from the wind turbine blade Wb by disengaging the connection of the support rod  130   a  to the aerial vehicle  300 . The aerial vehicle  300  can avoid colliding with the wind turbine blade Wb or wind turbine due to the effect of a strong wind, etc. by releasing the aerial vehicle  300  from the wind turbine blade Wb. 
     Fifth Step 
     The conductive member  120  is electrically connected with the receptor Lc of the wind turbine blade Wb while the conductive member  120  is fixed to the wind turbine blade Wb, whereby the receptor Lc of the wind turbine blade Wb is connected to a measurement device on the ground via the conductive member  120  of the aerial vehicle  100  and measurement cable (not shown), and the quality of electrical connection via a down conductor between a receptor and ground is determined with the measurement device on the ground. 
     Sixth Step 
     After electrical connectivity inspection, an instruction signal in a form of a wireless signal, etc. from the aerial vehicle  300 , etc. is transmitted to disengage fixture of the conductive member  120  to the receptor Lc by the fixing means  150 , whereby the conductive member  120  and the support rod  130   a  are released (natural drop) from the wind turbine blade Wb, as shown in  FIG.  8 B (b). 
     In this manner, the aerial vehicle  300  of Embodiment 3 was configured so that the aerial vehicle  300  is released from the wind turbine blade Wb when the conductive member  120  contacts with and is fixed to the receptor Lc. Thus, the risk of the aerial vehicle body  110  colliding with the wind turbine blade Wb can be averted. For this reason, the aerial vehicle  300  of the invention enables safe and simple electrical connectivity inspection on the conductor Lc of the wind turbine blade Wb. While the embodiment shown in  FIG.  8    describes a case where the conductive member  120  and the support rod  130   a  are released from the wind turbine blade Wb, the embodiment may be configured so that the conductive member  120  comprises the fixing means  150 , and only the conductive member  120  is released from the wind turbine blade Wb. 
     As disclosed above, the present invention is exemplified by the use of its preferred embodiments. However, the present invention should not be interpreted to be limited to such embodiments. It is understood that the scope of the present invention should be interpreted based solely on the claims. It is understood that an equivalent scope can be practiced by those skilled in the art from the specific descriptions in the preferred embodiments of the invention based on the descriptions of the present invention and common general knowledge. It is understood that any references cited herein should be incorporated herein by reference in the same manner as the contents are specifically described herein. 
     INDUSTRIAL APPLICABILITY 
     The present invention is useful in the field of aerial vehicles and electrical connectivity inspecting methods as an invention that can obtain an aerial vehicle which enables safe and simple electrical connectivity inspection on a structure and an electrical connectivity inspecting method using such an aerial vehicle. 
     REFERENCE SIGNS LIST 
     
         
           100  to  103 ,  200 ,  201 ,  300  Aerial vehicle 
           110  Aerial vehicle body 
           120  Conductive member 
           130  to  133 ,  230 ,  231  Moving mechanism 
           130   a,    131   a,    132   a  Support rod 
           130   b  Rod moving means 
           130   c,    230   c,    231   c  Coupling member 
           131   b  Rod extending/retracting means 
           132   d,    133   d  Rod rotation means (rotation mechanism) 
         Lc Lightning conductor 
         Wb Wind turbine blade