[vox] Ardupilot, UAVs, and linux.

[Alex Mandel]

On 11/11/2012 09:49 PM, Bill Broadley wrote:
> On 11/11/2012 12:18 PM, Alex Mandel wrote:
>> I haven't looked much at the other boards, the arduino has been a target
>> for me for the following reasons:
>>
>> Add-on shells for GPS, Camera, Storage and other sensors (8-16 sensors
>> or add ons depending on device).
> 
> Seems like the same add on sensors work with other boards.  The newer
> boards if anything have more IO.
> 
>> Community size (Plenty of prebaked stuff, good books)
> 
> Heh, well even the Arduino is moving to arm, the arduino Due is a 32 bit
> cortex M3, and most of the UAV folks seem to think that's too little too
> late.  At least the ardu pilot/copter folks are advocating skipping the
> Due and porting to the m4f.
> 

I'll follow whatever is common and obvious.

>> Ease of programming for the purpose
>> Low power consumption (the lower the better if it serves the purpose
>> right because you get longer flights)
>> Inexpensive, I've seen boards for as little as $50 (depending on the model).
> 
> I've not seen anything that cheap with enough sensors/control to do a
> UAV.  Something like this one:
> http://store.diydrones.com/APM_2_5_Kit_p/br-ardupilotmega-06.htm
> 
> $180 no GPS, $200 mediatek gps, $250 uBlox GPS.
> 
> Looks pretty similar to:
> https://store.diydrones.com/ProductDetails.asp?ProductCode=BR-PXFMU
> 
> Once you add the nice uBlox CPU for $75.99.
> 
> I'd be a bit surprised if the power was much different considering how
> much power the motors take.
> 
Ah you assume I'm talking powered flight, I've been looking at a sensor
platform with GPS, 4 Band camera and recording on time intervals that
can be adjusted to be used on any flying device, be it Kite, Balloon,
Zepplin, Plane, Heli or Quad/Octo copter.

The reality is that depending on where you want to fly (how big of an
area) and the quality of images you need, different vehicles are more
appropriate.

>> From a non CS perspective ease of actually getting the device to work
>> without having to delve into hardware drivers, C, etc is really
>> important. 
> 
> Agreed.  Several projects have working (turn key afaict) autopilots for
> the cortex m4f, but I guess the conservative thing to do is wait for the
> ardupilot/arducopter port.
> 

Possibly even cheaper to use a raspberry Pi
http://blog.makezine.com/2012/11/08/raspberry-pi-in-the-sky/

Apparently a 7th grader sent one up to 85,000 ft.
http://www.raspberrypi.org/archives/2386


>> Since the projects I work on have limited budgets we usually
>> have to go with whatever technical ability our Scientists (Geographers,
>> Ecologists, etc) have.
> 
> Sure, I suspect most folks just assemble it and either fly it live or
> use qgroundcontrol or related app to set 3d way points.
> 
>> Side note, right now we often use CHDK on Canon Powershot type cameras
>> to do intervalometers, because you can use cheap off the shelf cameras
>> and you can write the scripts in BASIC of all things.
> 
> Heh, cool.  Looks like the gopro is fairly common, as well.  I suspect
> they just hit record before they launch.  I've been curious is gopro
> supports some kind of API/SDK to allow similar.  They do offer a app
> that can control the camera from a smartphone.
>

No need to hack the GoPro it's one of the only cameras with
Intervalometer as part of it's stock settings. The downside of video
mode on many cameras is that you end up with lower quality images(HD 2 M
vs 10+ M), and then there's the whole thing of auto-focus, and making
sure you turn it off and fly high enough for the lens to simply shoot at
infiniti.


>> If others are interested their has been talk of a local PublicLab group
>> to help each other work on such platforms.
> 
> Sounds interesting to me.

Thanks,
Alex