BeagleBoard.org has just released a new product called the BeagleBone Blue. It has the same processor as a BeagleBone Black, but is designed specifically for robotics and includes built-in Wi-Fi/Bluetooth, an accelerometer and motor controllers (and more). I was fortunate enough to get my hands on a pre-release Blue when I met the BeagleBoard gang recently at the 2017 Embedded Linux Conference in Portland, OR. So, of course I had to hook it up to my LEGO Mindstorms stuff to see if it would work.
The first thing to do, of course, if figure out a way to attach the Blue to LEGO technic parts somehow. Fortunately, the BeagleBone mounting holes come close enough to lining up with LEGO stud/pin spacing that we can make something without having to resort to using a 3D printer. Here is what I came up with:
It is actually the same width as the NXT and EV3 bricks but is a bit smaller in the other dimensions.
To attach the Blue, I picked up some nylon M3 screws and matching standoffs. I went with nylon so that it wouldn’t tear up the plastic on the LEGO parts and because it would flex a bit since the holes don’t line up exactly. I used 8mm standoffs because that is very roughly the same as the width of a LEGO technic beam. 10mm or 12mm screws will work for passing through the LEGO technic beams. 4mm screws would be ideal for the BeagleBone side, but I couldn’t find any that short, so I cut off some longer ones. Tip: since the holes don’t line up, get the screws started on both sides of the standoff before tightening them all the way.