[sib]

The issue is not acceleration front/back, which can be dealt with in design and is fairly stable and consistent, but acceleration as much as 0.5G side/side, which is also more intermittent and against which it's difficult to build seats that would protect customers.

[Retric]

Really it's just a question of track design as these are 100% predictable G forces. If you really need to turn you can just roll the cabin and keep these g's directly under you and or slow down apraoching it. Elevators can also quickly have a fairly wide range (0.8 to 1.2) g's and people don't really get sick in them.

Highways for example have fairly wide banks which people rarely notice. https://sterlingpearce.files.wordpress.com/2015/02/img_0054....

[toomanybeersies]

Aeroplanes are probably a more accurate approximation of what you'd feel. You get hardly any G force from banked highways, your speed is just too low. Now I don't really get plane sick, I will quite happily sit through a few barrel rolls (which is far more extreme than the hyperloop (although that would be fun)), but there's plenty of people who would get sick from a few 1.5 G banked turns.

Elevators are different because you don't spend more than about 1 minute in an elevator.

[Retric]

High end cars can pull up to 1g lateral forces and many cars can pull up to 1g breaking on a good road surface. Relatively low top speed just means you don't accelerate very long. I have hit weightlessness over a hill at high speeds followed by 1.x g on the other side, so 0.5 g does not seem bad.

Remember 1g * 1 second is only ~22mph.

[toomanybeersies]

For sure, my car is a pile of junk and can hit 1g braking.

The problem is when it's sustained. That's why people get sick on roller coasters and when doing aerobatics (extreme examples, I know).

[Lazare]

That doesn't really solve it; there's limits on how much you can rotate the cabin, and how quickly you can rotate it. Lots of math here: https://pedestrianobservations.wordpress.com/2013/08/13/loop...