And it looks quite cool when in motion.
This design is rather open so it is possible to clearly see the lanes, but it might have been better to make the design more compact by removing about every other row and column.
A close up:
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and just in case somebody would like to know how it is done, then I prepared the following:
I start with a grid in 'diamond formation'. Power masts are convenient for this.
Around each mast I then put a crossing. It is crucial that all tunnels are alligned at this stage, in my case EW.
With that done I can remove the masts and finish the crosses:
The next step is then filling out all empty intersections.
It can be done by either placing a straight cross, - this time with the tunnels rotated 90 degrees, i.e. in my case NS.
Or by placing two bends. (I haven't rotated the orientation yet).
If this is done everywhere, then the result will automatically be a knotwork that alternates between tunnels and overpasses, - and with a bit of symmetry, then it can't avoid looking good.
(Some short loops or othewise creative thinking is needed at the edges.)
The final step is to add a temporary filling line, and the sit back and enjoy.
I recommend to play with this algorithm on paper first, as changing the orientation of belt back and forth is a pain if errors are found.
