That's an awesome construction, works almost like the real thing, except for the manual way you insert a bridge segment in the machine.

WOW that ended up being a lot more complicated than I was expecting! Fantastic work 😅

This is basically LEGO transport safety training gone wrong.

i would love to see this beefed up with knowledge of how this first version went to create a much better second version that is able to do everything without assistance. it would also be neat to see it have the ability to load train tracks in without having to lift up the entire train to put a new track section in

The main issue I can see, is that the screws moving your mobile lifter is too flexible.
something you could do to fix that is add a static slot on the sides of train that the lifter slides in, this would help combat the flexing as the lifter would be pushing against the train directly instead of via the screws.

I was literally looking for Lego vids to watch then this came up in my notifications

Successful! I can’t think of how you could have eliminated the sections where you lent a hand

The little crane that could

Successful, however, one thing I would change is for the bridge crane loader thing to have more room so it would have more bridge segments and load faster rather than manual labor. Otherwise, awesome job!

And then a smart person found out that they could just use a claw.

Unsuccessful ❌

Overcomplicated ✅

Still really impressive tho

This, is absolutely extraordinary. Fantastic!

When you mentioned about the lead screws being flimsy, it immediately reminded me of something I experienced in my childhood with K’nex; their largest standard rods were grey, and they could flex if needed. But they also had rods the same size that were black, and they didn’t flex at all.

If you showed Lego this video and told them about the K’nex thing, maybe they’ll eventually make a strong, non-flexing lead screw. I’m sure they’d take that feedback better from you than from me.

If you’re wondering about the bridge sections being unsecured, the bridge-building train is heavy enough to press the section down

Really nicely done. Some tips (from an engineer):
I think putting all the batteries at the rear section and, if possible, also some more of the motors. And it would be more stable.
Also, the rear motorised wheels and the big moving support legs need to be synched in moving speed. Then it would work without attaching the pillars together.

Nice work! Most I’d change is maybe trying to see it can be possible get it to where it can to rest on one adjusting foot and have the structure held down with more weight, it’d be interesting to see if it’s a scalable idea that can be specialized to do far lighter or different track gauges.
You could use a separate unit to be responsible for moving the bridge layer, but I think that’d require a second controller for that unit.

Makes me think of a LEGO Von Neumann machine - a LEGO machine that builds identical copies of itself, which are then in turn able to build more copies, ad infinitum, as long as it has a supply of resource bricks. Or even a LEGO machine that is able to build simple things out of LEGO.

7:16
Ideas. Motorise the wheels and have it lift up and move back rather then trying to life the whole thing with the foot. But that is an additional 3 motors.

I think it would be insanely cool if you could set the stud intervals between each beam and the machine could do it fully automatically

The second moveable foot needs more structural rigidity than just the two long lead screws. Perhaps this second foot should be more outboard than the first foot such that the first nests in between the second - this should help support the device when transferring the load from the first foot to the second foot. The lengths of each of the functional sections should be equal - it seemed that some sections were shorter than others. The technic structural truss beams should run the whole length of the horizontal crane.

I kept wanting you to put the battery boxes on a follow car and just run longer wires. But, great job. Just watched it with my son and he wants to build one now. Ugh. 😮😅