Due the high demand to built this awesome differential mechanism we decided to open source it even in this early stage.
Note that this is test fixture that we designed to test the mechanism for our future robots! 
You can find more info about it on GitHub:   https://github.com/PCrnjak/Differential-robot-wrist

How to make it?

Step 1 - Source all the parts from the BOM
Step 2 - print all the parts in STL folder (Note that some parts need to be printed twice)
Step 3 - Assemble the differential and calibrate the drivers
Step 4 - Program and test it! Example code!
Step 5 - Enjoy your differential mechanism!