Lego Mindstorm EV3 motors - some performance info under EV3DEV

I'm getting ready to write some nice control software for my Lego motors and have done some initial tests to see how they perform.

This graph shows how rpm varies with duty cycle, no load and powered by a rechargeable battery at 7.4v (the battery was under charge as well)

For real use normally one would use rpm regulated mode of course.

Unless you need the ultimate rpm, the large motor is a more consistent performer.

Mindstorming with Python

The motors that come with the Lego Mindstorms EV3 comes with motors with positional feedback and reasonably sophisticated controls. The 'brick' that interfaces with all the widgets can also easily be hacked to enable use of sensible programming languages rather than the visual language (which has some significant limitations) that Lego have developed.

The ev3dev update is especially good as it can easily be removed to revert back to the original state (it is installed on an SD card and no changes are made to the controller).

So here is a quick blog of what I have done to get up and riunning with python on the EV3. I did fall down a couple of bear pits along the way, so this describes how to get to a working solution.