I'm releasing Version 0.1.4 of the standard size Pigeon Post Smart Case. This is the version we'll be using to develope the different clamps/hooks/arms which the multi copters can use to pick the cases up.
The top plate and base can be placed next to each other to be printed and the sides of the case can be made very easily with card or thin plastic sheets.
In the new year want to use this or the next version in the competitions and challenges Pigeon Post will be running in the new year to test out some of the basic elements of the system. Here's some more images from Sketch Up: