Jon's Place

Sunday, February 14, 2016

Roz - Raspberry Pi

Its been a while since I posted here - life has been busy. The first revision of the power board had a couple issues, so we ended up doing a second revision. This second revision works great.

Power Board Revision 2

I 3D printed a mount for Roz so I could fasten both the power board and a raspberry pi 2. I also picked up a 2.8" touchscreen LCD from Adafruit, and also a spy camera (also from Adafruit). You can see the camera in the picture below - it is on the end of a long gold-colored flat cable, just in front of the head.

Roz


The raspberry pi 2 has a wifi module, and an Espruino Pico, which has been re-flashed with MicroPython. The pico is acting as a bus forwarder for the Bioloid bus, which contains the 14 servos, and the power board (which is also a device on the bus).

The screen will allow me to display status, and run debug routines, choose missions, and in general give me visibility into what's happening. The camera (which isn't mounted yet) will allow me to run SimpleCV, and thus add vision-based capabilities to Roz. I'll be designing and printing a new head for Roz to include the camera mount.

The other thing you can see in Roz's head is a LIDAR Lite, which is essentially a laser-based range sensor. I backed the company on their original crowd-funding campaign, and this seemed like a reasonable place to use it.

Having the power board allows me to hot-switch from battery power to wall power and back again, which is essential in my opinion for using an OS-based computer on a robot. I would have liked to incorporate a 3-cell charger into the board as well, but that will have to wait until version 2.