WO2021085588A1 - プロペラ - Google Patents

プロペラ Download PDF

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Publication number
WO2021085588A1
WO2021085588A1 PCT/JP2020/040775 JP2020040775W WO2021085588A1 WO 2021085588 A1 WO2021085588 A1 WO 2021085588A1 JP 2020040775 W JP2020040775 W JP 2020040775W WO 2021085588 A1 WO2021085588 A1 WO 2021085588A1
Authority
WO
WIPO (PCT)
Prior art keywords
propeller
obstacle
hub
lift
bent portion
Prior art date
Application number
PCT/JP2020/040775
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
アンヴァン ホ
ディン クアング グエン
Original Assignee
国立大学法人北陸先端科学技術大学院大学
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 国立大学法人北陸先端科学技術大学院大学 filed Critical 国立大学法人北陸先端科学技術大学院大学
Priority to JP2021553714A priority Critical patent/JP7236171B2/ja
Publication of WO2021085588A1 publication Critical patent/WO2021085588A1/ja

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H1/00—Propulsive elements directly acting on water
    • B63H1/02—Propulsive elements directly acting on water of rotary type
    • B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
    • B63H1/14—Propellers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H1/00—Propulsive elements directly acting on water
    • B63H1/02—Propulsive elements directly acting on water of rotary type
    • B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
    • B63H1/14—Propellers
    • B63H1/26—Blades
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
    • B64C11/02—Hub construction
    • B64C11/04—Blade mountings
    • B64C11/08—Blade mountings for non-adjustable blades
    • B64C11/12—Blade mountings for non-adjustable blades flexible
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C11/00—Propellers, e.g. of ducted type; Features common to propellers and rotors for rotorcraft
    • B64C11/16—Blades
    • B64C11/20—Constructional features
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C27/00—Rotorcraft; Rotors peculiar thereto
    • B64C27/32—Rotors
    • B64C27/35—Rotors having elastomeric joints
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C27/00—Rotorcraft; Rotors peculiar thereto
    • B64C27/32—Rotors
    • B64C27/46—Blades
    • B64C27/473—Constructional features
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/26—Rotors specially for elastic fluids
    • F04D29/28—Rotors specially for elastic fluids for centrifugal or helico-centrifugal pumps for radial-flow or helico-centrifugal pumps
    • F04D29/30—Vanes

Definitions

  • the present invention relates to a propeller.
  • An airplane propeller is a device that includes a plurality of rotary blades (blades) attached to a rotating shaft, and obtains thrust or lift by rotating these blades.
  • Propellers are also used in small unmanned aerial vehicles, so-called drones.
  • Patent Document 1 describes a propeller provided with a rotary blade having a shape suitable for hovering a drone.
  • This propeller comprises a rotor with long chords near the axis of rotation and stability suitable for hovering.
  • Patent Document 2 describes a propeller made of a flexible material.
  • the rotating shaft and rotor blades of this propeller are made of a flexible material.
  • the propeller described in Patent Document 1 includes a wing having a shape optimized for maximizing flight time and load.
  • the wings of this propeller are formed into an unchanging shape for maximum flight time and load. Therefore, the rigidity of the propeller described in Patent Document 1 is high, and there is a problem that the wing is permanently deformed when the propeller collides with another object.
  • an object of the present invention is to provide a propeller that easily returns to its original shape even if it is deformed during rotation.
  • the propeller according to one aspect of the present invention is In the center and A blade formed so as to extend outward from the central portion, A bent portion including a flexible member connecting the central portion and the blade, and a bent portion. Fibers arranged inside the bent portion and stretched between the central portion and the blades, and To be equipped.
  • the blade of the propeller according to the present invention includes a front edge portion located on the front side in the rotation direction.
  • the front edge portion may have flexibility.
  • a propeller that easily returns to its original shape even if it is deformed during rotation is provided.
  • FIG. 1A It is a perspective view of the propeller which concerns on 1st Embodiment. It is a top view of the propeller shown in FIG. 1A. It is a front view of the propeller shown in FIG. 1A. It is a side view of the propeller shown in FIG. 1A. It is a flowchart which shows the flow of the manufacturing method of the propeller shown in FIG. 1A. It is a perspective view of the propeller which concerns on a comparative example. It is a graph which shows the measurement result of the experiment which compared the propeller shown in FIG. 1A and the propeller shown in FIG. 3A. It is a figure which shows the image before and after the propeller shown in FIG. 1A comes into contact with an obstacle.
  • FIG. 1A It is a figure which shows the image immediately after the propeller shown in FIG. 1A came into contact with an obstacle. It is another figure which shows the image immediately after the propeller shown in FIG. 1A comes into contact with an obstacle. It is another figure which shows the image immediately after the propeller shown in FIG. 1A comes into contact with an obstacle. It is another figure which shows the image immediately after the propeller shown in FIG. 1A comes into contact with an obstacle. It is another figure which shows the image immediately after the propeller shown in FIG. 1A comes into contact with an obstacle. It is a top view of the propeller which concerns on another comparative example. It is a top view of the propeller which concerns on another comparative example. It is a top view of the propeller which concerns on another comparative example. FIG.
  • FIG. 7B is a diagram showing an image immediately after the propeller shown in FIG. 7B comes into contact with an obstacle. It is a figure which shows the image immediately after the propeller shown in FIG. 7C came into contact with an obstacle. It is a figure which shows the image immediately after the propeller shown in FIG. 7A came into contact with an obstacle. It is a graph which shows the measurement result of another experiment which compares propellers shown in FIG. 7A to FIG. 7C. It is a top view of the propeller which concerns on another comparative example. It is a top view of the propeller which concerns on another comparative example. It is a top view of the propeller which concerns on another comparative example. It is a graph which shows the simulation result which compares propellers shown in FIGS.
  • FIG. 9A to 9C It is a perspective view of the propeller which concerns on another comparative example. It is a figure which shows the position of the tip of the wing part of the propeller shown in FIG. 7B. It is a figure which shows the position of the tip of the wing part of the propeller shown in FIG. 10A. It is another figure which shows the position of the tip of the wing part of the propeller shown in FIG. 7B. It is another figure which shows the position of the tip of the wing part of the propeller shown in FIG. 10A. It is a graph which shows the measurement result of another experiment which compares the propeller shown in FIG. 7B and the propeller shown in FIG. 10A. It is a graph which compares the lift measured by an experiment with the predicted lift.
  • the propeller 1 according to the first embodiment of the present invention is, for example, a two-blade propeller attached to a drone.
  • the propeller 1 bends a hub 11 which is a central portion capable of rotating, a wing portion 12 including a pair of blades extending outward from the hub 11, and the hub 11 and the wing portion 12.
  • a flexion portion 13 that is possibly connected, a deformable edge 14 provided at the edge of the wing portion 12, and a plurality of fibrous tendons 15 that are embedded in the flexion portion 13 and connect the hub 11 and the wing portion 12 To be equipped.
  • the extending direction of the wing portion 12 shown in FIG. 1A will be described as the + Y direction
  • the direction in which lift is generated will be described as the + Z direction
  • the directions perpendicular to the Y and Z directions will be described as the + X direction.
  • the hub 11 is arranged at the center of the propeller 1.
  • the hub 11 is a central portion that connects the rotation axis of the propeller 1 with other members of the propeller 1.
  • a hole H for connecting to the rotation shaft of the motor M (not shown) is threaded in the Z direction.
  • the hub 11 includes an annulus R and a transition portion T formed so as to continuously and smoothly project radially outward from the annulus R. At one end of the transition portion T, the hub 11 is connected to the bent portion 13.
  • the hub 11 contains a rigid plastic material having high rigidity, for example, ABS resin or PLA (polylactic acid) resin.
  • the wing portion 12 contains a highly rigid hard plastic material.
  • the blade portion 12 is formed in a shape that functions as a rotary blade (blade) of the propeller 1 integrally with the deformable edge 14 described later.
  • the specific shape of the propeller 1 may be calculated theoretically or by simulation, and is not limited to the shapes shown in FIGS. 1A to 1D.
  • the bent portion 13 contains a material having higher flexibility than the hub 11 and the wing portion 12, for example, silicone rubber. Further, the rigidity of the bent portion 13 is lower than the rigidity of the hub 11 and the wing portion 12.
  • the bent portion 13 is arranged between the hub 11 and the wing portion 12, and is formed in a continuously changing shape that smoothly connects the transition portion T located on the outside of the hub 11 and the inside of the wing portion 12. Has been done. By bending the bent portion 13, the wing portion 12 can be displaced in the vertical direction and the rotational direction.
  • the deformable edge 14 is a front edge portion provided on the edge of the wing portion 12 in the rotation direction D.
  • the rotation direction D is counterclockwise in the propeller 1.
  • the deformable edge 14, like the bent portion 13, contains a material that is more flexible than the hub 11 and the wing portion 12, such as silicone rubber.
  • the rigidity of the deformable edge 14 is lower than the rigidity of the hub 11 and the wing portion 12.
  • the wing portion 12 is an example of the rear wing portion in the claim
  • the deformable edge 14 is an example of the front edge portion in the claim.
  • the tendon 15 is a thread-like member containing a flexible and high-strength fiber material, for example, nylon fiber. As shown by the broken line in FIGS. 1A to 1C, a plurality of tendons 15 are stretched between the hub 11 and the wing portion 12, and the periphery thereof is covered with the flexion portion 13. The rigidity of the tendon 15 is lower than the rigidity of the flexion portion 13, and the flexibility of the tendon 15 is higher than the flexibility of the flexion portion 13.
  • the hub 11 and the wing portion 12 have low flexibility, while the bent portion 13 has high flexibility and the tendon 15 having high strength connects the wing portion 12 to the hub 11. There is. Therefore, when the propeller 1 receives an external force, the wing portion 12 and the deformable edge 14 are displaced by the external force, but when the external force disappears, the wing portion 12 and the deformable edge 14 are quickly returned to their original positions. Further, since the propeller 1 contains only a partially flexible material, twisting and vibration due to rotation are reduced as compared with the case where the propeller 1 is entirely composed of the flexible material.
  • step S1 the shape of the propeller 1 is designed (step S1). Specifically, for example, using numerical calculation software, a simulator, CAD (Computer Aided Design) software, etc., each component of the propeller 1, that is, a hub 11, a wing portion 12, a bending portion 13, a deformable edge 14, and the like can be used. Design the shape.
  • CAD Computer Aided Design
  • a hard part may be formed by molding using a mold as in the method in the molding step described later without using a 3D printer.
  • the hard part and the tendon 15 are adhered to form a frame which is the skeleton of the propeller 1 (step S3). Specifically, since small holes are formed on the surfaces of the hub 11 and the wing portion 12 facing each other, the tendon 15 coated with the adhesive is inserted into these small holes and fixed. For adhesion, an adhesive suitable for both the hard part and the tendon 15 is used.
  • step S3 The frame formed in step S3 is placed on the mold and positioned (step S4).
  • the mold used in this step is formed in advance by a method such as 3D printing from the data of the space occupied by the hub 11, the wing portion 12, the bending portion 13, and the deformable edge 14 generated in the design step.
  • step S5 For example, a mixture of the main material and the curing agent is poured into a mold and gently held until it hardens.
  • step S6 Separate the molded product from the mold (step S6). In this step, excess parts, so-called burrs, are removed from the molded product.
  • Fine adjustment is performed by applying an adhesive to the mutually contacting portions of the hub 11, the wing portion 12, the bent portion 13, and the deformable edge 14 (step S7). As a result, the hard part and the soft part of the propeller 1 are more firmly connected. Propeller 1 is completed through the above steps.
  • the propeller was connected to the rotation shaft of the motor M, and the rotation speed of the motor M could be set arbitrarily by changing the current supplied to the motor M.
  • the rotation speed of the propeller is equal to the rotation speed of the motor M.
  • FIG. 3B shows the relationship of lift (N) with respect to the rotational speed (rpm) of the motor M.
  • the lift generated by the propeller 1 is linearly increased as in the lift generated by the conventional propeller 101.
  • the lift obtained by using the propeller 1 is about 22.6% smaller than the lift obtained by using the conventional propeller 101.
  • the rotation speed it was obtained that the lift force of the propeller 1 can be obtained to the same level as that of the conventional propeller 101.
  • the lift produced by the flexible propeller 1 is smaller than the lift produced by the conventional propeller 101 having the same shape.
  • the flexible propeller 1 can generate lift equivalent to that of the conventional propeller 101. Therefore, even if the conventional propeller 101 is replaced with the flexible propeller 1, it is considered that the flight of the drone will not be hindered.
  • 4A-4D and 5A-5D are high-speed camera images taken before and after the moment when the propeller 1 and the propeller 101 touch the ribbon, respectively.
  • 4A to 4D and 5A to 5D are all arranged in the order in which time has passed.
  • FIGS. 6A to 6E are high-speed camera images taken after the propeller 1 comes into contact with an obstacle, respectively. 6A to 6E are arranged in the order in which time has passed.
  • the images shown in FIGS. 6A and 6B are an image immediately after one of the wing portions 12 of the propeller 1 comes into contact with an obstacle, and an image immediately after the other comes into contact with an obstacle. From these images, it is understood that when the wing portion 12 comes into contact with an obstacle, the propeller 1 bends significantly at the bent portion 13.
  • the image shown in FIG. 6C is an image in the process of pulling out an obstacle upward while rotating the propeller 1. From this image, it is understood that the wing portion 12 twists downward to avoid obstacles.
  • the images shown in FIGS. 6D and 6E are images immediately after the obstacle is removed. From these images, it is understood that when the obstacle is removed, the shapes of the wing portion 12 and the bent portion 13 are restored.
  • the propeller 1 collides with an obstacle and is deformed.
  • the time required to return to the original shape is also about 0.4 seconds.
  • the bent portion 13 bends, twists, and returns to an obstacle in a relatively short time of less than 1 second. It is understood that the impact force due to contact with is absorbed.
  • the bent portions 213 to 413 include a flexible material like the bent portion 13, but are molded using a material that is harder than the bent portion 13.
  • FIGS. 8A-8C show changes in shape immediately after the propellers 301, 401, and 201 collide with a resin prism imitating a human finger, respectively.
  • “Frame n” represents an image at the moment of collision
  • “Frame n + 1” represents an image one frame after the moment of collision.
  • the temporal intervals between adjacent frames are equal, about 1 millisecond.
  • only representative frames are shown in FIGS. 8A-8C.
  • the bent portions 213 to 413 are shortened, the time required to return to the original shape after colliding with the obstacle can be shortened, and if the bent portions 213 to 413 are shortened too much, the obstacles can be shortened. It is understood that it becomes vulnerable to.
  • FIG. 8D measures the lift generated by the propellers 201 to 401 by changing the rotation speed of the motor M. At almost all motor M speeds, propellers 201, 301, and 401 produced the largest lift in that order.
  • propellers 501-701 differ in that they do not have a deformable edge 14.
  • the bent portion 813 of the propeller 801 according to the comparative example does not include a tendon.
  • the bent portion 813 is arranged so as to overlap the hub 11 and the wing portion 12, and the bent portion 813 and the hub 11 and the bent portion 813 and the wing portion 12 are joined to each other.
  • the pin 816 is driven in the direction indicated by the arrow in each of the portion of the bent portion 813 that overlaps with the hub 11 and the portion that overlaps with the wing portion 12.
  • the propeller 301 according to the comparative example is formed in the same shape as the propeller 801.
  • the propeller 301 includes a tendon 15 at the flexion portion 313 as well as the flexion portion 13.
  • the tip of the wing portion 12 of the propeller 301 is a scale of a ruler arranged parallel to the rotation axis and points to 43.5 mm.
  • the tip of the wing portion 12 of the propeller 801 is a scale of a ruler arranged parallel to the rotation axis and points to 35.5 mm.
  • the tip of the wing portion 12 of the propeller 801 is 8.0 mm lower than that of the propeller 301.
  • 11A and 11B are measurements of the magnitude of the force required to deform the tips of the blades 12 of the propellers 801 and 301 until they reach the same position in a stationary state.
  • the tip of the wing portion 12 of the propeller 301 was a scale of a ruler arranged parallel to the rotation axis and pointed to 67.0 mm.
  • the magnitude of the force required to push down the tip of the wing portion 12 of the propeller 301 to the reference position by 23.0 mm was 0.120 N.
  • the tip of the wing portion 12 of the propeller 801 was a scale of a ruler arranged parallel to the rotation axis and pointed to 58.5 mm.
  • the magnitude of the force required to push down the tip of the wing portion 12 of the propeller 801 to the reference position by 16.5 mm was 0.039 N.
  • the magnitude of the force required to deform the propeller 301 with the tendon 15 to the reference position is about 3 the magnitude of the force required to deform the propeller 801 without the tendon to the same reference position. It is understood to be double. Therefore, it is understood that the tendon 15 contributes to improving the rigidity of the propeller 1. Further, it is presumed that the material of the bent portion 13, the material and diameter of the tendon 15, the number of tendons 15, and the like affect the rigidity of the propeller 1.
  • the propeller 801 generated a smaller lift than the propeller 301 in the rotating state. Further, it was obtained that the difference in the magnitude of the lift generated by the propeller 801 and the propeller 301 increases as the rotation speed of the motor M increases. Further, at a rotation speed of the motor M exceeding 2000 rpm, the flexion portion 813 of the propeller 801 without the tendon 15 is damaged, so that the measurement itself cannot be performed. It is considered that these results were obtained because the propeller 801 without the tendon 15 is more strongly affected by the centrifugal force as the rotation speed of the motor M increases as compared with the propeller 301 with the tendon 15. Be done. Therefore, it is understood that the tendon 15 maintains the shape of the entire propeller 1 at a high rotation speed and contributes to improving the lift of the propeller 1.
  • 11D and 11E compare the magnitude of lift generated by the propellers 801 and 301 with the simulation. In the simulation, it was expected that the lift will increase as the rotation speed of the motor M increases. The experimental results are almost in line with the simulation, and as the rotation speed of the motor M increases, the lift generated by the propellers 801 and 301 also increases.
  • a hard obstacle RO is connected to the tip of the force sensor FS, and propellers 1 and 101 are attached to the drone DR.
  • the propellers 1 and 101 were rotated to fly the drone DR and collide with the collision area CA of the obstacle RO, and the impact force applied to the obstacle by the propellers 1 and 101 was read through the force sensor FS.
  • both propellers 1 and 101 applied the maximum impact force to the hard obstacle RO about 3 ms after the moment of collision.
  • the maximum impact force given to the hard obstacle RO by the propeller 1 was about 10 N
  • the maximum impact force given to the hard obstacle RO by the propeller 101 was about 67 N.
  • the magnitude of the impact force applied to the hard obstacle RO by the propeller 1 did not exceed the magnitude of the impact force applied to the hard obstacle RO by the propeller 101.
  • Propeller 1 has been described as having two blades, but the number of blades is not limited to this.
  • the propeller 21 according to the second embodiment of the present invention has two pairs of four blades in total.
  • the shape of each of these four blades is the same as the blades of the propeller 1, that is, the blade portion 12, the bending portion 13, and the deformable edge 14.
  • the four blades are arranged at 90 ° intervals about the rotation axis. According to the propeller 21, since the area of the blades is larger, vibration during flight can be reduced as compared with the propeller 1 having two blades.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structures Of Non-Positive Displacement Pumps (AREA)
  • Toys (AREA)
PCT/JP2020/040775 2019-10-31 2020-10-30 プロペラ WO2021085588A1 (ja)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2021553714A JP7236171B2 (ja) 2019-10-31 2020-10-30 プロペラ

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2019198143 2019-10-31
JP2019-198143 2019-10-31

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WO2021085588A1 true WO2021085588A1 (ja) 2021-05-06

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WO (1) WO2021085588A1 (enrdf_load_stackoverflow)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2022189652A (ja) * 2021-06-11 2022-12-22 株式会社石井鐵工所 ドローン用プロペラのブレード
JP2023040693A (ja) * 2021-09-10 2023-03-23 国立大学法人北陸先端科学技術大学院大学 ドローン及びドローンの制御装置
CN119568383A (zh) * 2024-09-29 2025-03-07 中国船舶集团有限公司第七一九研究所 一种可展开的环形螺旋桨及跨域航行器

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JPS5424200B1 (enrdf_load_stackoverflow) * 1969-05-20 1979-08-18
JP2003247342A (ja) * 2002-02-01 2003-09-05 Weyerhaeuser Co 木製厚板、木製厚板に使用する端部キャップ、及び木製厚板を損傷から保護する方法
US20160347441A1 (en) * 2015-06-01 2016-12-01 Northrop Grumman Systems Corporation Deployable propeller
US20190135419A1 (en) * 2017-11-03 2019-05-09 Vantage Robotics Llc Foldable unmaned aerial vehicle (uav)

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US4627791A (en) 1982-11-10 1986-12-09 Marshall Andrew C Aeroelastically responsive composite propeller
US5108262A (en) * 1990-03-23 1992-04-28 The United States Of America As Represented By The Secretary Of The Navy High damping flexible propeller/impleller
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JPS5424200B1 (enrdf_load_stackoverflow) * 1969-05-20 1979-08-18
JP2003247342A (ja) * 2002-02-01 2003-09-05 Weyerhaeuser Co 木製厚板、木製厚板に使用する端部キャップ、及び木製厚板を損傷から保護する方法
US20160347441A1 (en) * 2015-06-01 2016-12-01 Northrop Grumman Systems Corporation Deployable propeller
US20190135419A1 (en) * 2017-11-03 2019-05-09 Vantage Robotics Llc Foldable unmaned aerial vehicle (uav)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2022189652A (ja) * 2021-06-11 2022-12-22 株式会社石井鐵工所 ドローン用プロペラのブレード
JP7664616B2 (ja) 2021-06-11 2025-04-18 株式会社石井鐵工所 ドローン用プロペラのブレード
JP2023040693A (ja) * 2021-09-10 2023-03-23 国立大学法人北陸先端科学技術大学院大学 ドローン及びドローンの制御装置
JP7713227B2 (ja) 2021-09-10 2025-07-25 国立大学法人北陸先端科学技術大学院大学 ドローン及びドローンの制御装置
CN119568383A (zh) * 2024-09-29 2025-03-07 中国船舶集团有限公司第七一九研究所 一种可展开的环形螺旋桨及跨域航行器

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JPWO2021085588A1 (enrdf_load_stackoverflow) 2021-05-06

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