Multiple Raspberry Pi 3D scanner

Original project found on Instructables.

Hardware

fabric used for pi management
twisted used for networking
- twisted isn't installed by default on the pi. You can install it on all pis using fabric: fab pi_setup. This requires the pi to be connected to the internet.

Assumed setup

All pis have a camera attached & enabled, are connected to a network and are turned on
All pis have twisted installed
A 'central command' computer to run scripts is also connected to the same network

Steps

Get the IP addresses of all pis, put the last number of each into a file in this directory called picam_ips.txt (one number per line). Eg. If a pi has the address 192.168.1.7, put 7 in the file. This process can be automated once all pis are running the listen script. I guess you could just put the numbers 1-255 in picam_ips.txt to be sure that all pis are accounted for.
Copy config_template.py to config.py, modify it to suit your requirements
Run fab deploy on the central command computer. This will copy necessary files to all connected pis.
Run fab start_listener to tell all pis to start listening for commands. You have to ctrl-c out of this, since I don't know how to start a background process with fabric yet :(. This should still leave listen.py running on the pis.
Run ./rolecall.py to check which pis are running listen.py. Note that this will overwrite picam_ips.txt.
Run ./send.py, enter a name for a photo. All pis should take a photo at this point. If you've configured them to save to a network location, photos should start appearing there. Otherwise, the central computer will start collecting photos from all the pis.
If you update config.py or listen.py, run fab redeploy to push out the changes and restart the listener on all pis.

Fix fab start_listener. Currently need to ctrl-c out of it.
Speed up taking a picture. Currently takes about 7 seconds - maybe use the picamera python module to directly interface with the camera in the listen script.