Here's a long needed update about the whole project!
The HeliShield is working and the design is now human friendly too. PCBs will be available shortly, email me if you'd like to buy one and I'll take your details and let you know when they're ready.
There will be a few ways in which you can buy the boards, bare single sided boards will be available in the next week without silkscreen. This option is not for the faint of heart, there are four leadless packages to solder on. The first PCBs sell for £15 each and will be supplied with documentation. The features on this board are as follows:
Radio baseband signal is captured on one pin.
Servo output headers for all channels
3 axis accelerometer
Single axis gyro for yaw
Dual axis gyro for roll and pitch
3 axis magnetometer for heading hold and dead-reckoning
Lots of smoothing caps
Draws power for everything directly from the speed controller
Serial header for connection to a wireless serial modem
Socket for IR rangefinder to enable gentle landings
A bit further in the future a double sided shield will be available, with silkscreen and the same spec as above. This will be the same footprint as the arduino.
Using the stock duemilanove with this board is testing it a bit, it runs stably doing all the inertial measurement, radio, serial comms bi-directionally and so on but there is very little room to expand either hardware or software. If you intend to just use a standard duemilanove I would suggest leaving out the magnetometer.
Having played with a Mega the other day, I've decided to stop the development around the Sanguino and move to the mega chip for the all-in-one system. This is on the drawing board at the moment, I will push for getting a test one done very soon, my current prototype is very hard to fit to a 450. The all in one system will be narrow enough to fit into the bodywork of a 450 size heli.
Come and have a look at the shiny new prototype at www.eclipseaudioservices.co.uk/extras/helicopter.html
Code is available for this board on the site now, and all the documentation will be appearing soon.
If you want to purchase a board in any state of completion, please email me with details of what you want and I'll get building.