UAV/UAS sense and avoid

[John Pritchard]

Hi,

I've learned that one of the primary systems on UAS's to be permitted into regulated airspace around here will be a 360 degree (meaning complete sphere) "sense and avoid" detection for all weather conditions (including rain!).  

Any comments on how to do this in an ultra light way (budget counting in milligrams and milliamps) would be interesting..  My own thought is radar -- although I don't know too much about it, especially in rain & clouds.

For the moment, I'm working on getting my model helicopter to fly (project "libra") -- in a way that develops tools and skills for very variable projects.  That is, I'm working in gEDA to develop a flight control computer to interoperate via wifi with something like an android phone -- in a table driven design & development process intended to permit the rapid application of changes on the requirements level.  So parts and board sets are defined in tables, and symbols and schematics are generated from these tables.  (Making common tasks easy & repeatable).  In this way it's easy to iterate development over requirements.  These tools are in https://github.com/syntelos/geda-libra

Best,

John

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http://www.google.com/profiles/jdp.ulsf.net

[jeyram jadenthradevan]

how about SAR?
http://en.wikipedia.org/wiki/Synthetic_aperture_radar
(just a thought - may be wrong )

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http://groups.google.com/group/ultra-light-space-flight?hl=en

[Tobias Krieger]

I'm not sure if I understand the question right, but if you meant to "sense and avoid" contact with other air vehicles, you should head for MODE-S Transponder (best with a TCAS system). There are some very small ones for ultralights.

See ya,

Tobias

 

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http://groups.google.com/group/ultra-light-space-flight?hl=en

[John Pritchard]

I'm not sure if I understand the question right, but if you meant to "sense and avoid" contact with other air vehicles, you should head for MODE-S Transponder (best with a TCAS system). There are some very small ones for ultralights.

See ya,

Tobias

Yes, I would think that aviation transponders apply.  However the "sense and avoid" function is more basic.  

An alternative in development elsewhere employs a number of video cameras with object recognition processing -- and plan to add something (presumably RF based) for cases where the visual mode is not applicable.  I think the RF solution is more "ultra light", skipping the visual set altogether.

[John Pritchard]

how about SAR?
http://en.wikipedia.org/wiki/Synthetic_aperture_radar
(just a thought - may be wrong )

Yes, a more particular kind of radar.. I don't know enough to comment..  Maybe an application analysis begins with craft velocity (relative to possible objective targets)?

 

[Joshua]

Yeah,
This is the old idea of PicoRover, it is to use a SAR of few hundred
of meter range but for UAS, as Tobias said, it is better to use
transponder (Secondary radar)
Best,
Joshua
BTW: This saturday at 12:00 UTC Balloon launch in Zaragoza

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> http://groups.google.com/group/ultra-light-space-flight?hl=en
>

[John Pritchard]

BTW: This saturday at 12:00 UTC Balloon launch in Zaragoza

Yeah,
This is the old idea of PicoRover, it is to use a SAR of few hundred
of meter range but for UAS, as Tobias said, it is better to use
transponder (Secondary radar)
Best,
Joshua

 

oh, i thought a transponder was just an automated RF rx/tx for tail number.

[Joshua]

There are few modes about transponder. Mode-C gives information about
altitude and Mode-S gives traffic trend.
Best,
Joshua

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> http://groups.google.com/group/ultra-light-space-flight?hl=en
>

[Tobias Krieger]

No, a transponder, depending on mode, can report also altitude, position, speed, direction, aircraft type, max speed...back to ATC. Mode S Transponder can also be used to communicate between A/C for Traffic Collision and Avoidance System (TCAS).

.tobias

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http://groups.google.com/group/ultra-light-space-flight?hl=en

[John Pritchard]

No, a transponder, depending on mode, can report also altitude, position, speed, direction, aircraft type, max speed...back to ATC. Mode S Transponder can also be used to communicate between A/C for Traffic Collision and Avoidance System (TCAS).

.tobias

Mode-S is interesting.. thanks