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Comment by namibj | Hacker News Reader

Notably the system works for substantially larger swinging angles (the structure gets somewhat heavier to leave that much more free space), and one could bank the track in turns, too. Together some impressive g forces could be archived; 1 horizontal g for a total of sqrt(2) would be barely beyond the wuppertal geometry's capabilities; 2 horizontal g for sqrt(3) total are still fairly realistic if the passengers/cargo tolerate.

You basically save having to go through mountains to keep speed, as you can go through a curvy valley.

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Passengers have fairly low tolerance for forces on a daily traveling mode of transport. Your average commuter wants to be able to hold a hot coffee without scalding themselves.

Genuine question: wouldn’t we still be able to do that? Im imagining similar behavior to swinging cup of water around on a string. The liquid experiences the same acceleration and “settles” within the new orientation of the container.

Yes the same as an airplane turning, you don’t spill your coffee on a banked turn

so long as the turn is coordinated! https://pilotinstitute.com/turn-coordinator/

yeah, one major problem with rail based transport, including monorails, is that you can't bank that heavily because there will be normal situations where the train goes into a curve slower than the max design speed.

Self-tilting trains exist, but are expensive, and hard to maintain.

2 g horizontal results in sqrt(2^2+1^2)g = sqrt(5)g swinging out at tan^(-1)(2) = 63.5 degrees from the perpendicular direction (probably overswinging a bit depending on track design and speed). Would be good fun on a commute. Hopefully the inner part of the superstructure doesn’t come out of the ground.

Not on that rail, though. That's one of the most boring rides ever, regarding swinging, or g-forces. They don't go more than 50kph ever, the highest I've ever seen was 45. Of course there is the novelty of hanging monorail and views, but otherwise? Meh...

That rail initially had a concession for 15 km/h. And I was pretty sure it ran up to 60 these days?

Also, boring is good. Though do not be fooled by the hidden g-forces: the tilting behavior turns the side ways forces into just you being a little heavier. The prototype track back then had a run with a wheel setup that had twice as much tilt angle as the current deployment, and to my understanding the current deployment does not bank the track. That's where (almost) 4x gains in allowed operational bank angle would be hidden.

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