[chbot] Real Robotics, Lego style...

[Mark Atherton]

Just been given access to a pile of Mindstorms stuff, so thought I would 
take a peek under the hood.

The EV3 controller (ARM9) is a bit old now (2012 vintage) but the entire 
project (HW and SW) appears to be open source; this came as a bit of a 
surprise.

Someone has also created a Debian based release 
(https://www.ev3dev.org/) of the OS. This can be independently booted 
from the micro-SD card without meddling with main processor code.

The hardware has a USB host which supports various tiny USB/WiFi dongles 
so it is quite easy to SSH, and SCP into one of these units.

The motors are actually true servo motors. The motor assembly has motor, 
gear-train, and opto shaft-encoder. The EV3 main unit has power H 
bridge, and optical quadrature decoder to allow position feedback. 
Presumably someone has implemented a PID controller to manage this mess; 
all-in-all it's just like a real servo.

For those of us while like breaking (or at least stressing systems) this 
is quite fun https://www.youtube.com/watch?v=bWgTRHH656Y

And for those of us who still leave a trail of socks around the house 
see https://www.youtube.com/watch?v=28smqHhq4GA at 2:18, this is an 
inspired piece of engineering.

Kids play as it all may be, it certainly opens up some interesting 
opportunities to quick-build mechanical prototypes.

-Mark