SB-XC based balloon launched HA UAV

[HALE_UAV]

Hey Guys,

I am currently doing a thesis as part of the University of Sydney's UAV project of a balloon launched low-cost High Altitude (20km-->65000ft) UAV based on the RnR SB-XC glider. I have been tasked with the non-navigation Integrated Sensor Suite.


The current plan is:
* Microchip PIC18f452
* 16bit or 24bit ADC (Any suggestions?)
* Motorola MPX5010 (airspeed)
* Motorola MPVZ5150 or All Sensors 15PSI-A-4V (Barometric/altitude)
* Texas Instruments TMP100 or National Semiconductor LM134 (internal, external, chip temperatures)
* Aiptek Pencam 1.3 SD (Digital imaging)
* Licor LI-200X-L (UV intensity)
* Apogee IRTS-P (Surface temperature when in low-level flight)

Currently in research stage but need to know payload capacity and payload dimensions for the SB-XC (can't find it anywhere including in the docs sent with the glider).

Your help would be greatly appreciated.

What do you guys think? any suggestions?

[zik]

I'd recommend the SCP1000 for the barometric altimeter. It's a little easier to work with than the Motorola ones.

[danstrider]

I have several images in the gallery of the web link below to give you a size scale. I'll have to measure when I get a chance (hopefully today). For reference, you can get a 2liter soda bottle in pretty easily.

I weighed my aircraft yesterday at just over 5kg, so you can weigh the empty airframe and figure out how much more weight can go in. I have also seen the plane fly over 7.71kg though, so there is certainly more potential. A really quick payload weight build up of my autopilot and batteries is 642g. I do have 100g of nose ballast too.

See: http://soaring.goosetechnologies.com

Keep us updated!
Dan

[Magician]

HALE UAV,

Sounds like a great research project. You might want to check out this press release (http://arcturus-uav.com/newsitem_01.php) from Arcturus. They dropped their electric T-15 from 65,000 feet using a Piccolo autopilot. Looks like all went well. And if you look close, you'll see a Piccolo autopilot in Dan's SBXC. Might be a good way to go.

Best of luck!

Chris

[HALE_UAV]

Hey guys thanks for the replies and advice.

Zik, I saw the SCP1000 and liked it because it was digital and didn't require A/D but looking at the specs it only goes to 30kPa and I need down to 5.5kPa. If you know a version that does that please let me know.

Dan, Thanks heaps for that. Thats a lotta room (2 liter bottle). Problem is that the project is fitting a motor and using an autopilot so it doen't leave much room/ weight for me. Cheers for the pics and weight info!

Chris, had a look at the Arcturus and yeah really interesting. I think the guy in charge of Nav is looking into the Piccolo Autos so I'll point him to there. If you're interested in this stuff, have a look at:
- the ARES mars scout mission (balloon launched flight trials)
- BIG BLUE (A university of Kentuckey project)
- Vanden Berg's High Altitude Glider Project (awesome Canadian hobbyist project)

Will keep this post updated with progress and pics (and no doubt questions) as time goes on.

Cheers
Matt

[zik]

Hi Matt,

Take a look at the Intersema MS5540B - it goes down to 10mBar and has a digital interface. You can also get similar gage pressure sensors for your airspeed which have a digital interface. This might allow you to do away with the high resolution A->D altogether and just use the PIC's internal 10-bit A->D for your other inputs.

Cheers,
Zik

[dmgoedde]

I'd recommend the SCP1000 for the barometric altimeter. It's a little easier to work with than the Motorola ones.

Be careful - the SCP1000 has lower limit pressure of 30kPa, which covers only up to about 30,000 feet ASL.

Dean

[danstrider]

Okie dokie, here's one with a motor and a Piccolo ...

So after searching through pictures, I don't have a terrific shot showing both the Piccolo and the motor at once. Suffice to say, it's definitely possible to get a full electric power system and battery inside with *plenty of room left for a Piccolo and servos.

Weight-wise, the NASA plane was carrying a 6s3p of 2000mah cells if I recall correctly. The motor was something hacker, like an A30 with a 6:1 gearbox. I have the specs somewhere if you reallllllly need them. Point was, the SBXC will fly heavy. If you have to skimp weight on the autopilot with that plane, you might should pick a different airframe; autopilot work is 10x harder than finding a lighter plane!

Also to note, the Piccolo II has extra A/D channels open for extra sensors that can be logged with the telemetry data (i.e. timestamped with the other data!). I somewhat get the feeling you're looking for some extra functionallity beyond the Piccolo...

Dan

[HALE_UAV]

Hey,

Dan, thanks for the info and the pics. Caught up with the autopilot/engine Engineer this week and yeah similar to what you're saying:

-Piccolo 2
-Hacker C50
-two 5s batteries

Yeah, I know the Piccolo has A/D channels, in fact a PC-104 is likely for mission comp. Atm though the plan is to keep things as modular as possible and integrate.

Hey I read in a thread you were looking into piccolo II as well. Any idea on the altitude limit on the barometric altimeter?

Hey anyone out there used the Hi-Cam aerial video system like Aerosonde? any good?
www.hicam.com.au

Cheers,
Matt

[danstrider]

I just got a Piccolo II to replace the Piccolo Plus. I don't have a good idea on the limits, but I know the Arcturus guys would have already asked that question. I'm pretty sure they're headed to 100k, but not sure if they had to do hardware mods to get there.

Aerosonde is using a TASE Gimbal from CCT last version I saw at AUVSI Conference in August.

Dan