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Flexible monocopter drone can be completely rolled up

spectrum.ieee.org

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Re: Flexible monocopter drone can be completely rolled up

#41

Post by dotancohen »

aclatuts wrote: post #22

I wonder if it could be even better and lighter with carbon fiber instead of basla wood.

Probably not by much. Balsa wood is extremely light, cheap, and easy to form into a wing. It is also easily repairable.

The real weight savings would probably come from the motor - and a carbon fiber casing might work here instead of the presumably steel casing currently in use. And though shaving weight off the wing would almost certainly move the center of mass further outwards, shaving the mass off the motor would move it further in. That might be detrimental, though, as the motor needs some leverage on the COM for this design.

This is a terrific project that invalidates many traditional ideas that we have about flying machines.

Re: Flexible monocopter drone can be completely rolled up

#42

Post by alexvoda »

tromp wrote: post #21

If you added a vertically oriented 1-dimensional camera, i.e. a single column of pixel sensors, then it could automatically extend that into 360 degree video.

Don't these cameras require to be stabilized? You only have one column of pixels so you can not correctly align the columns through stitching (as in panorama mode on phones).

As impressive as the stabilization used is that these dromes manage to hover in roughy the same spot (instead of drifting everywhere), I do not believe it will be sufficient for a rotating line camera.

Re: Flexible monocopter drone can be completely rolled up

#44

Post by michaelmior »

alexvoda wrote: post #42
tromp wrote: post #21

If you added a vertically oriented 1-dimensional camera, i.e. a single column of pixel sensors, then it could automatically extend that into 360 degree video.

Don't these cameras require to be stabilized? You only have one column of pixels so you can not correctly align the columns through stitching (as in panorama mode on phones). As impressive as the stabilization used is that these dromes manage to hover in roughy the same spot (instead of drifting everywhere), I do not believe it will be sufficient for a rotating line camera.

I don't know how well it would work, but I think you could still perform alignment using a single column assuming that you would expect to see patches with the same color connected together more often than not. Especially if you're trying to do video since then you can also exploit temporal coherency (meaning that you expect many objects to be stable over time). I'm sure in my head it's much simpler than practice, but it seems like it is achievable at least in theory.

Sounds like a very fun problem for computer vision researcher to work on. Probably not terribly difficult to generate a bunch of test data from existing 360 cameras by downsampling.

Re: Flexible monocopter drone can be completely rolled up

#45

Post by cutemonster »

BasilPH wrote: post #25
moffkalast wrote: post #7

That does not fly in the way I initially presumed it does.

I would never have thought of something flying like that. It's a nice reminder for me that we don't know what we don't know.

I also thought the small propeller would point upwards (rather than to the side).

Now afterwards it feels so obvious.

First i thought, but the propeller, it's so small

Turns out the whole thing was the propeller :-)

Re: Flexible monocopter drone can be completely rolled up

#46

Post by jcun4128 »

phire wrote: post #38
thenewwazoo wrote: post #35

Earlier quoted context omitted.

It spins at ~5 Hz. 5 fps isn't great, but this is a cool idea.

Use 6 of them, each facing at 60 degree angles. That would give you 6 updates per spin, for ~30hz video.

that would be cool, then you could do your visual inertial odometry stuff with that data, even if low quality might be like working with IR

Re: Flexible monocopter drone can be completely rolled up

#47

Post by ncmncm »

alexvoda wrote: post #42
tromp wrote: post #21

If you added a vertically oriented 1-dimensional camera, i.e. a single column of pixel sensors, then it could automatically extend that into 360 degree video.

Don't these cameras require to be stabilized? You only have one column of pixels so you can not correctly align the columns through stitching (as in panorama mode on phones). As impressive as the stabilization used is that these dromes manage to hover in roughy the same spot (instead of drifting everywhere), I do not believe it will be sufficient for a rotating line camera.

The column images can be tagged with samples from an onboard gyro and compass. The stitcher does not need to rely only on the pixels themselves. Normally the next pass will be pointing a little higher or lower, so such annotations will be essential.

Re: Flexible monocopter drone can be completely rolled up

#48

Post by adfm »

14 wrote: post #14
fvdessen wrote: post #10

It folds into a small storage tube, is lightweight, has good autonomy, makes little noise, and safely autogyrates to the ground on failure. If you could somehow add a camera and stabilise it, it could make an excellent search drone for search / rescue / military ops.

What would be the advantage over existing drone technologies? Look at these autonomous drones [0]that can fly through the forest at high speeds. High speed, highly maneuverable and can hold other equipment like a camera. [0] https://electronics360.globalspec.com/article/17357/video-fl...

Since it folds into a cylindrical shape, it's easier to transport and could potentially be fired off from something like a grenade launcher. It's the computer vision and shaped charge that I'd worry about.

Re: Flexible monocopter drone can be completely rolled up

#49

Post by snovv_crash »

londons_explore wrote: post #9

I tried to do a similar thing with a single actuator frisbee. The goal would be a frisbee with a single fin could fly anywhere when launched out of some high power launcher. The goal was to make a single-use aircraft which could go anywhere in a city for under $1. By making the aircraft unpowered and under 250g, lots of regulations no longer apply, and it becomes practical to use them to deliver small items. The fin…

To counteract the gyroscopic effect you'd need 2 frisbees with attached axes spinning in opposite directions. Lots of choices for which way to arrange them - side-by-side, forward-back, vertically, some staggered formation...

Re: Flexible monocopter drone can be completely rolled up

#50

Post by moffkalast »

cutemonster wrote: post #45
BasilPH wrote: post #25

Earlier quoted context omitted.

I would never have thought of something flying like that. It's a nice reminder for me that we don't know what we don't know.

I also thought the small propeller would point upwards (rather than to the side). Now afterwards it feels so obvious. First i thought, but the propeller, it's so small Turns out the whole thing was the propeller :-)

The real propeller was the friends we made along the way
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