This powerhouse of a circuit board will knock your socks off! In fact, one might assume that Mighty Mouse is manning the cockpit of your UAV (Unmanned Aerial Vehicle). Here comes ArduPilot Mega to save the day! Designed by Chris Anderson (Wired Magazine's Editor-in-Chief) and Jordi Muñoz of DIY Drones, this product is so awesome it deserves its very own homepage post.
Check out the insane amount of IOs - booya!
First off, this beast uses the new ATMega1280, giving you tons of additional processing power and 54 pins of IO madness. This means you can connect many more sensors and control up to eight servos. Like its smaller cousin, it still has a failsafe feature controlled by the onboard ATMega328. This allows you to manually override the autopilot, maintaining control via your RC transmitter. The ATMega328 comes pre-programmed with the failsafe firmware. The ATMega1280 comes with the Arduino Mega bootloader, allowing you to tweak the code to your liking using the free Arduino software and our FTDI basic.
Jordi and his DIY Drones UAV at the 2010 Autonomous Vehicle Competition. This plane was running the previous version of the ArduPilot. Look Ma...no hands!
The autopilot handles both stabilization and navigation, eliminating the need for a separate stabilization system. It also supports a "fly-by-wire" mode that can stabilize an aircraft when flying manually under RC control, making it easier and safer to fly. The hardware and software are all open source. The board comes with all the surface-mount parts already soldered, but requires the user to solder on connectors. Other necessary elements, including aircraft recommendations, can be found at the project's home page.
This is an exciting product for anyone interested in steppin up their autonomous vehicle game. ArduPilot Mega is the greatest wingman you could ask for...think Goose in IC form.
"tons of additional processing power"
Really? Who's maths was that :-p
If anything, this has less processing power than the older one, since the ATMega1280 is a 16MHz AVR and the ATMega328 is a 20MHz AVR...
Bigger != faster
I was going more for speed != power. The ATMega1280 can handle a heavy load. It's like...a Porsche can out race a semi-truck, but I'd like to see that Porsche haul 15 tons of lumber! :)
Much (if not all) of the Ardupilot's functionality depends on GPS. I'm going to bet that the water will block the GPS signal, so I doubt that it will be usable as-is for undersea navigation.
If I flew a UAV automatically to the competition from California would I win? =)
You'd have my vote!
"125kHz can work under water"
Quoted from http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=128
I'm just talking theory, but I KNOW that it can be done, just a matter of choosing the right frequency, antenna length, distance required.
Actually that is a apx. attenuation value at 10kHz, not 44-90 MHz as for the tv signal. But regardless it was apx, and related to frequency. And my local station it broadcast from 10.2 miles from me on top of a mountain at 20.6 kW. That's alot of power to reach the town 10 miles away. But we get it, even though the attenuation.
It can be done, it is done daily, and we can all do it too, some math and research and BAM.
In a nutshell, I'm trying to promote experimentation and not just believing someone that says no when they only say no because of their own closed mindedness.
I've suffered from too many people saying no, and then me proving them wrong.
Research, test, try. And never say never.
Okay, that's just cool.
Has anyone tried a controller like this for undersea navigation? One major drawback to ROV control is the need for an umbilical because RF signals just don't work well underwater. I wonder if this could be adapted to allow autonomous control of underwater vehicles?
Think about it - you could put some obstacles in that lake everyone keeps driving their cars into and next year SparkFun could attack the AVC by air, land AND sea!
RF works great underwater, I'm just not too sure about the frequencies. But as long as you broadcast/receive into the water, it should work.
Think about subs, and the great distances they communicate. Low bitrates I expect but.
Basically it can work and work well underwater. But probably at lower than 2.4GHz. Maybe the 320MHz chips would work nice.
Damn, now I want to try it out. I don't need another project.
But a UUV would be awesome. Sneaky sneaky. =)
unfortunately, i don't think so =( the underwater military subs use VLF (very low frequency) for more than 30 ft underwater. they get VERY low bandwidth (on the order of hertz). Typically they send over this band when there's something important the sub needs to receive, and then it goes closer to the surface and launches an antenna to receive the full high bandwidth coded message. Unfortunately, transmitting at these low frequencies is not trivial at all (wavelength is ENORMOUS, and most transmitters are very low efficiency)
However, I'd imagine some other mhz-range frequencies might get a couple of feet out of the water. 2.4ghz is very clearly not going to work--think about how your microwave works (water absorbs 2.4ghz and heats up)
Actually the real answer is that it depends. I build and design RC subs, and I can tell you that you can get a great signal into water that is not too full of minerals and other things to make it conductive. As soon as the conductivity of water increases, the signal gets attenuated significantly more. We run using 75mhz with no problem. I also know that there are systems for divers that have radio communications, and I have seen them used in salt water, I am assuming that the transmission distance is relatively small, though I do not have too much experience with them, nor do I know what frequency they use. One problem is that using an antenna that has been "optimized" (I use that term loosely) for air is far from being optimized for water. I have read a few papers that suggest that ideal antennas for water are actually much smaller than those for air due to the fact that the EM waved travel much slower in water changing the wavelength (though not the frequency).
Adam
Oh, I gotcha, I wasn't meaning 2.4GHz, I was meaning somewhere in the low-mid kHz or High Hz range.
I know the Elf is used for extreme long distance (5000+ miles).
"it is necessary to use very low frequencies (10 to 30 kHz) where attenuation is in the order of 3.5 to 5 dB per metre."
"The potential for operation in fresh water is much better. Using the Adelaide water sample, attenuation at 10 kHz is only 0.4 dB per metre rising to 5.4 dB per metre at 1.8 MHz"
source:
http://www.qsl.net/vk5br/UwaterComms.htm
Air has an attenuation of about .15 dB per meter on avg(I think). So at 10khz, maybe 1/3 total distance vs. air.
Seems possible. I gotta do some tests in the tub now.
NewsparkFunCusty: _
Air has an attenuation of about .15 dB per meter on avg(I think). So at 10khz, maybe 1/3 total distance vs. air.
Seems possible. I gotta do some tests in the tub now._
So when you receive a TV broadcast from a transmitter 10 miles away the loss is around 2500 dB? Do satcom links overcome tens of thousands of dB??
negative. This is not how RF energy propagates.
"125kHz can work under water"
Quoted from http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=128
I'm just talking theory, but I KNOW that it can be done, just a matter of choosing the right frequency, antenna length, distance required.
Actually that is a apx. attenuation value at 10kHz, not 44-90 MHz as for the tv signal. But regardless it was apx, and related to frequency.
It can be done, it is done daily, and we can all do it too, some math and research and BAM.
In a nutshell, I'm trying to promote experimentation and not just believing someone that says no when they only say no because of their own closed mindedness.
I've suffered from too many people saying no, and then me proving them wrong.
Research, test, try. And never say never.
Why not use us sonic or ultrasonic frequencies? Audio travels great underwater at 3x the speed it does through air. It works great for whales so why not an ROV? You could always make a repeater that takes rf frequencies from your radio and converts them to audio and send that to an underwater transducer. Just a thought.
We sell some acoustic modems that work great for underwater comms at desertstar.com. They're something like 2k though so you might be better off getting some ceramic elements and trying to build your own and using ours/other acoustic modems as a reference.
that would be a little bit of awesome!
YES!!! I would most definitely take part in a AUV competition!