Hello.
The original model (Mk. I. on video) has for over a year. And about its modernization, I began to think almost immediately after its creation.
But proceed to the practical part decided just a couple of months ago.
And in the holidays, I finished it - NanoWalker Mk. II.
The model was slightly longer and slightly higher - the price paid for new transmission.
I've tried, probably, a dozen variants, while receive a workable.
The main feature of the new version - the ability to move in different directions.
LDD-file (both versions)