AERIAL RECONNAISSANCE DRONE AND METHOD

Abstract

An aerial reconnaissance drone having a dragonfly format (elongate fuselage and flapping wings) with two cameras having respective diagonal fields of view, arranged at respective ends of the fuselage, both pointing forwards, wherein the second camera has a diagonal fielder of view that is at most half that of the first camera. This has the advantage of providing a drone that can capture enhanced imagery when required, by performing a half turn and switching which camera is being used. Since this avoids placing two cameras in the same location both can have a clear view of surroundings yet it helps avoid off balance caused by placing too much mass in any particular off-centre location.

Claims

1. An aerial reconnaissance drone apparatus comprising: an aerial drone comprising an elongate fuselage and four wings arranged to provide lift by flapping, and first and second cameras having respective square/rectangular fields of view and respective diagonal field of view angles, wherein the first camera is arranged at a front end of the fuselage, pointing forwards, and the second camera is arranged at a rearward end of the fuselage, pointing rearwards, and wherein the second camera has a diagonal field of view angle that is at most half of a diagonal field of view angle of the first camera; and a remote control unit configured to wirelessly transmit instructions to the aerial drone and receive imagery therefrom, wherein the aerial drone is configured to move as instructed and to transmit imagery back, and wherein the remote control unit comprises a user interface comprising a display configured to display such imagery, wherein the remote control unit is arranged to provide a user with an option to switch between two imagery modes, wherein the remote control unit and drone are arranged such that upon selection, the drone rotates as to substantially reverse orientations of the cameras and the display switches from displaying imagery from one camera to displaying imagery from the other camera, and, wherein the second camera has a diagonal field of view width that is at most half that of the first camera.

2. The aerial reconnaissance drone of claim 1, wherein the first camera has a diagonal field of view angle of between 80 and 230 degrees, and the second camera has a diagonal field of view angle of between 1 and 80 degrees.

3. The aerial reconnaissance drone of claim 1, wherein the first camera is an illuminator.

4. The aerial reconnaissance drone of claim 1, wherein the second camera comprises a mirror element.

5. A method of using a drone for aerial reconnaissance, the method comprising: providing an aerial drone comprising an elongate fuselage and four wings arranged to provide lift by flapping, and first and second cameras having respective square/rectangular fields of view and respective diagonal field of view angles, wherein the first camera is arranged at a front end of the fuselage, pointing forwards, and the second camera is arranged at the rearward end of the fuselage, pointing rearwards, and wherein the second camera has a diagonal field of view angle that is at most half that of the first camera; and providing a remote control unit configured to wirelessly transmit instructions to the drone and receive imagery therefrom, wherein the drone is configured to move as instructed and to transmit imagery back, and wherein the remote control unit comprises a user interface comprising a display configured to display such imagery, wherein the remote control unit is arranged to provide a user with an option to switch between two imagery modes, wherein the remote control unit and drone are arranged such that upon selection, the drone rotates so as to substantially reverse the orientations of the cameras and the display switches from displaying imagery from one camera to displaying imagery from the other camera, and, wherein the second camera has a diagonal field of view width that is at most half that of the first camera; and selecting the option to switch between two imagery modes, the drone performing a half turn, and the display switching from displaying imagery from one camera, to displaying imagery from the other camera.

Description

[0014] Preferred embodiments will be described by way of example only, with reference to the figures in which:

[0015] FIG. 1 shows a side view of a known dragonfly style drone; and

[0016] FIG. 2 shows a side view of a drone according to an embodiment of the invention, with a remote control unit.

[0017] Referring to FIG. 1 a dragonfly style drone is shown. It has two wings either side of an elongate fuselage, and a single camera at the front.

[0018] FIG. 2 shows an embodiment of the present invention. By comparison with the prior art drone of FIG. 1, it has one camera at either end of the fuselage, each pointing outwards. The cameras have differing fields of view (measured diagonally with respect to a square/rectangular image sensor within each camera). The cameras may not have identical resolutions, but the angular resolution of the second camera is generally smaller than the angular resolution of the larger camera. In general the focal length of the second camera is longer than that of the first camera, typically by a factor of at least two.

[0019] Generally the fields of view are fixed (barring any small changes caused by focal adjustment), as this offers an advantage in terms of weight reduction and/or light collection. However if they are not fixed (e.g. in the case of zoom lenses) the smallest available field of view achievable that can be automatically (rather than manually) adjusted to during use should be taken as the field of view of that camera. For example the first camera preferably has a diagonal field of view of between 80 and 230 degrees, preferably of between 90 and 150 degrees. And the second camera preferably has a diagonal field of view of between 1 and 80 degrees preferably between 2 and 50 degrees, preferably between 3 and 20 degrees.

[0020] Generally speaking there is provided an aerial reconnaissance drone having a dragonfly format (elongate fuselage and flapping wings), with two cameras 4′, 4″ having respective diagonal fields of view 5′, 5″, arranged at respective ends of the fuselage, both pointing forwards, wherein the second camera has a diagonal field 5″ of view that is at most half that 5′ of the first camera 4′.

[0021] In any embodiment preferably one or both cameras is a mirror-lens camera wherein substantially each of the optical elements of the lens is a mirror. A mirror lens is a term of art, and may often contain no lens elements, or may contain one or a small number of lenses, often being small lenses. Preferably the second camera has a mirror lens. The advantage is that a larger amount of light can be collected without increasing the weight of the drone, and this approach particularly suits a drone with two fixed focal length cameras since mirror lenses typically do not adjust focal length or do so only minimally or with severe detrimental tradeoffs.

[0022] In any embodiment preferably at least one of the cameras is also an illuminator. Preferably this is achieved by incorporating a light emitting array (E.g. LED's) as a front layer of the sensor, such that the sensor can direct light via the respective lens so as to be collimated to be directed in one or more controlled (E.g. user-defined via the GUI, or automatically selected) directions. Preferably the light emitting array substantially overlies the whole sensor, such that the camera can illuminate in any direction that it can view. Viewing and illumination may not be possible at the same time, however it is preferably possible to illuminate in pulses of light, between image frames collected by the sensor, so that the illuminator and image recording can occur alternately.