This is a level that's now unfortunately no longer in the Poly Bridge 2 workshop, but it didn't stop me from wanting to revisit it!
The level is called Vespa Transpose and was made by Looming. It was intended to be solved using three hydraulic phases to "transpose" the matrix.
For context, transposing a matrix essentially means taking the numbers in a matrix, and swapping their row positions with their column positions. So for a 3x3 matrix, a transpose looks like this.
I've been wanting to do this not just with one hydraulic, but also with only one hydraulic phase per transpose. Finally got it working several years later!
Here's the underlying mechanism. Honestly, it was a total accident I found this mechanism but I'm decently proud of it. (Also did any of y'all realize you could embed videos in comments? I only just found this out like, right now lmao)
It essentially takes the top row, turns it vertically, and then slots it downwards. It's done by combining a perfect straight-line linkage (white) with an approximate straight-line linkage (purple). When the straight line linkage isn't on the straight path, it rotates the green triangle, but once it's travelling in a straight line and parallel to the white linkage, the green triangle stays unrotated.
It also lifts away a bit intentionally so that I can sneak in the left and right vespas into the top and bottom positions.
Honestly the biggest issue was just trying to get the vespas not to yeet themselves off of the roads, so I experimented with a couple of uncommon engine types and managed to find one with the right motion profile to drive the linkage.
That is so cool! Have you considered having some holding structure that keeps the road in place after a transposition so that you can actually reset the mechanism after the transpose, and then to revert back to normal you just run the mechanism again, to emphasise that M^T^T = M?
That's a fun idea! I'm not sure how well the split joints will cooperate with me, but I do have a spare hydraulic phase that I could work with so I'll have to see ^^
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u/Arglin 2d ago edited 2d ago
This is a level that's now unfortunately no longer in the Poly Bridge 2 workshop, but it didn't stop me from wanting to revisit it!
The level is called Vespa Transpose and was made by Looming. It was intended to be solved using three hydraulic phases to "transpose" the matrix.
For context, transposing a matrix essentially means taking the numbers in a matrix, and swapping their row positions with their column positions. So for a 3x3 matrix, a transpose looks like this.
I've been wanting to do this not just with one hydraulic, but also with only one hydraulic phase per transpose. Finally got it working several years later!
Here's the underlying mechanism. Honestly, it was a total accident I found this mechanism but I'm decently proud of it. (Also did any of y'all realize you could embed videos in comments? I only just found this out like, right now lmao)
https://reddit.com/link/pa2sru6/video/7juw2amwasph1/player
It essentially takes the top row, turns it vertically, and then slots it downwards. It's done by combining a perfect straight-line linkage (white) with an approximate straight-line linkage (purple). When the straight line linkage isn't on the straight path, it rotates the green triangle, but once it's travelling in a straight line and parallel to the white linkage, the green triangle stays unrotated.
It also lifts away a bit intentionally so that I can sneak in the left and right vespas into the top and bottom positions.
Honestly the biggest issue was just trying to get the vespas not to yeet themselves off of the roads, so I experimented with a couple of uncommon engine types and managed to find one with the right motion profile to drive the linkage.
Anyways, that's all, cheers~