Discussions

UPDATE: project page available at http://www.varesano.net/projects/hardware/FreeIMU

In the past months I worked a lot on accelerometers, gyroscopes and digital compasses. I'm now pretty intimate with the ADXL345, the ITG3200 and the HMC5843.

I've been able to design and construct homebrew DIY breakout board PCBs for all of them (ADXL345 and ITG3200) and to create a nice library to use them which also implement a great sensor fusion algorithm capable of running on the Arduino without problems.

I'm now making the next step. Let me introduce FreeIMU.

FreeIMU is a 9 DOM/DOF MARG IMU based on the ADXL345, the ITG3200 and the HMC5843. As this is part of my Master of Science Project and that I completely share the openness of projects like Arduino, FreeIMU will be completely open: all the designs will be released under a Creative Commons Attribution-ShareAlike 3.0 Unported while all the software will be release under GNU GPL v3.

As my background is in computer science, I'm quite self-taught in PCB designs and in electronics in general. So, I'm now seeking review for FreeIMU's schematics and PCB designs. If you have experience working with IMUs, designing PCBs or circuits and you would like to contribute to a free project please have a look at the designs and feel free to comment it.

I'm using kicad as schematics and PCB editing software. It's free (as in speech) software and, once you get around its glitches, it works really well. Using non-free software like EAGLE to design a free hardware like FreeIMU would have been simply senseless.

Note: I'm using a nightly updated version of Kicad, so if you have problems opening the files you might need to update your version of Kicad.

So, you'll find the current Kicad based sources of FreeIMU here. You'll also need a library of components which is here. For your convenience there's also a pdf version of the schematics.

I plan to submit FreeIMU to DorkbotPDX PCB Order of the 13th December to have it constructed. I currently don't see this as a commercial project but if someone is interested in FreeIMU I could sell a couple of boards.

Ok, so.. looking forward to hear your comments. Thanks!