New to Quads, Interesting question

[wooden]

As Darkwolf mentioned, the 2.1 kit is more suited to additional features, the v1.9 kit really suffers from the lack of code space available on the Atmega328. 2.1 uses an Arduino Mega2560, which has 10x the flash memory and can easily hold all the information necessary for using all the sensors AQ is designed to be compatible with. Had we chosen AQ for our project from the beginning, we would've chosen the 2.1 kit but we had already spent a little money building a KKMultiCopter board and didn't want to spend any more than we had to, plus I already had an Arduino Uno which saved us even more.

For altitude hold, you can either use a barometer or rangefinder. A barometer will work at any altitude while a rangefinder needs to be within range of the ground. The MaxBotix rangefinders AQ is designed for only have a range of about 255 inches, give or take a few. We used a rangefinder for our autolanding code because we needed the altitude relative to the ground, a barometer can't tell you where the ground is.

If you can swing it, get the 2.1 kit. Your school may have a way to get the Arduino Mega2560 cheaper but you won't find a better deal on the sensors/shield anywhere other than AQ. You could save a little money by opting for the SparkFun 6DOF sensor instead of the 9DOF (9DOF just includes a magnetometer that really isn't 100% necessary unless you want absolute heading capabilities as opposed to relative heading capabilities just using the z-axis gyro). 6DOF is $35 cheaper than the 9DOF.

[fb39ca4]

If one was to get the 6DOF board with the Mega 2.1 shield, could they add on a separate magnetometer board in the future?

[wooden]

Yep, you'd just have to change the defines in the code a little bit.

[fb39ca4]

But is there room on the board to attach both?

[wooden]

Physically? I'm not sure, I don't own a 2.1.x shield. The Arduino Mega2560 has plenty of room for the code, though.