[Canberrauav] Keeping on track.
Jack Pittar jpittar at bigpond.net.au 
Fri Jan 21 22:38:01 EST 2011 

Hi team.

Have a look at this website. It looks like we are to be presented with a
Mugin.
http://www.fpvflying.com/categories/FPV-UAV-RC-modelplanes/

Our aircraft will be more like the Hugin, also on this site. It will have a
moderate wing loading, and be reasonably fast. It will be quite steady, and
not be affected very much by wind or turbulence.  It will handle minor
tumbles and heavy landings with minimal damage. It will be designed around
our equipment, including antennas and odd shaped electronic equipment. It
will never hover.

Whatever we go with, we need two, with interchangeable parts.

The rascal is a nice aircraft. It is very light, and quite fast.  This
design is typically subject to turbulence. It is an expensive ready built
aircraft. I am guessing our load will be in the order of 10KG. At this
weight, it will not stand up to many bad takeoffs or even good landings.

I have purchased all the items for the latest ardupilot mega (APM),
including the ublox GPS.  I have loaded ArdupilotMega Version 1.0, and tried
a few of the servo driving tests on it. Right now, I am concentrating on
building another aircraft. Then I will get the APM working on it.  I
considered playing with the simulator, but really, I think it may lead us up
a blind alley and have us worrying about all sorts of things that may not
turn out to be a problem.

Maybe we need a meeting earlier than Thursday to get us on track, bring the
recent members into the picture, and who would like to concentrate on what.

I will be meeting a prospective new member to the Model Aircraft club on
Saturday afternoon, 3:30. He wants to know if he can use video and play with
telemetry at the field! I will also be there Sunday morning with a new plane
or an old one patched up.

Jack.

[Canberrauav] Keeping on track.
tridge at samba.org tridge at samba.org 
Sat Jan 22 11:48:02 EST 2011 

Hi Jack,

 > Our aircraft will be more like the Hugin, also on this site.

Do you know what the limits on size and weight of onboard electronics
will be?

If we want the possibility of automatically finding the target then
we'll need a lot more CPU power than we can get with a Arduino. There
are lots of possible on-board computers we could use. Here are a few
likely choices:

gumstix: 
	 http://www.gumstix.com/store/catalog/product_info.php?products_id=256
	 weight: 43g 
	 size: 17mm x 58mm x 4.2mm
	 cpu: 600MHz ARM A8 + a DSP core
	 memory: 256M
	 cost: $229
	 has a USB host adapter for a camera

beagleboard-xM:
	http://beagleboard.org/hardware-xM
	weight: 37g
	size: 76mm x 76mm x ??mm
	cpu: 1GHz ARM A8 + a DSP core
	memory: 512M
	has a 4 port USB hub
	cost: $139

pandaboard:
	http://pandaboard.org/
	size: 102mm x 114mm x ??mm
	weight: 74g
	cpu: dual core 1GHz ARM A9
	cost $174
	has 2 USB host ports plus a OTG USB port
	memory: 1GB

If the pandaboard will fit in the cargo bays of the Hugin then I think
we should go for it as the extra CPU power will make a huge difference
for image processing.

All of them have low power usage. It looks like the pandaboard uses
around 4W when both CPU cores are running and about 2W when idling
(using a 5V DC source - see
http://www.omappedia.org/wiki/Panda_Test_Data)

If you think the pandaboard will fit in the Hugin OK and nobody else
has a better suggestion (Matt?) then I'll order one for us to
experiment with.

I know that we may end up deciding to do the target finding manually
using a groundstation and a human, but I think we should get the
equipment needed to have the possibility of finding the target
automatically.  If we don't end up using it then it just means I have
another little embedded system to play with at home.

Cheers, Tridge

[Canberrauav] Keeping on track.
Jack Pittar jpittar at bigpond.net.au 
Sat Jan 22 14:04:13 EST 2011 

Hi Trige,
The aircraft will be designed around the equipment, even if it turns out to
be a funny looking aircraft.
I would prefer the computer to be mounted in a plug-in module up to 150 by
150 so you can take it home and play with it by yourself, but if the
computer becomes a structural part of the aircraft, so be it.
Power will come from batteries and an onboard generator. Keep your power
requirement down, but don't waste time by trying to skimp too much either.
Jack.

-----Original Message-----
From: tridge at samba.org [mailto:tridge at samba.org]
Sent: Saturday, 22 January 2011 11:48 AM
To: Jack Pittar
Cc: canberrauav at canberrauav.com
Subject: Re: [Canberrauav] Keeping on track.


Hi Jack,

 > Our aircraft will be more like the Hugin, also on this site.

Do you know what the limits on size and weight of onboard electronics
will be?

If we want the possibility of automatically finding the target then
we'll need a lot more CPU power than we can get with a Arduino. There
are lots of possible on-board computers we could use. Here are a few
likely choices:

gumstix:
	 http://www.gumstix.com/store/catalog/product_info.php?products_id=256
	 weight: 43g
	 size: 17mm x 58mm x 4.2mm
	 cpu: 600MHz ARM A8 + a DSP core
	 memory: 256M
	 cost: $229
	 has a USB host adapter for a camera

beagleboard-xM:
	http://beagleboard.org/hardware-xM
	weight: 37g
	size: 76mm x 76mm x ??mm
	cpu: 1GHz ARM A8 + a DSP core
	memory: 512M
	has a 4 port USB hub
	cost: $139

pandaboard:
	http://pandaboard.org/
	size: 102mm x 114mm x ??mm
	weight: 74g
	cpu: dual core 1GHz ARM A9
	cost $174
	has 2 USB host ports plus a OTG USB port
	memory: 1GB

If the pandaboard will fit in the cargo bays of the Hugin then I think
we should go for it as the extra CPU power will make a huge difference
for image processing.

All of them have low power usage. It looks like the pandaboard uses
around 4W when both CPU cores are running and about 2W when idling
(using a 5V DC source - see
http://www.omappedia.org/wiki/Panda_Test_Data)

If you think the pandaboard will fit in the Hugin OK and nobody else
has a better suggestion (Matt?) then I'll order one for us to
experiment with.

I know that we may end up deciding to do the target finding manually
using a groundstation and a human, but I think we should get the
equipment needed to have the possibility of finding the target
automatically.  If we don't end up using it then it just means I have
another little embedded system to play with at home.

Cheers, Tridge

[Canberrauav] Keeping on track.
tridge at samba.org tridge at samba.org 
Sat Jan 22 14:46:09 EST 2011 

Hi Jack,

 > I would prefer the computer to be mounted in a plug-in module up to 150 by
 > 150 so you can take it home and play with it by yourself, but if the
 > computer becomes a structural part of the aircraft, so be it.

ok, the pandaboard fits in that space requirement (102mmx114mm), so
I'll order one. 

 > Power will come from batteries and an onboard generator. Keep your power
 > requirement down, but don't waste time by trying to skimp too much
 > either.

The pandaboard will draw about 2W continuous, rising to 4W when under
heavy load. eg. if using both CPUs doing image processing.

We could get away with a smaller onboard computer, but having a
dual-core 1GHz A9 will give us heaps of power for some quite
sophisticated algorithms. 

The pandaboard doesn't have firewire, but I can't find a suitable
board that does have firewire. That limits our camera choices a but,
although I've noticed that some of the fly cameras from pointgrey have
USB2.0 as well, which we can use on the pandaboard.

Cheers, Tridge

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