A question: "Lateral force"

[gerstlaueringvar]

It's the same thing, but I bet you want to experience -1G on a roller coaster instead of hanging yourself upside down, right?

[MFJorts]

I think how you enter the element is an important factor. Sure, at a snapshot in time, hanging upside down is -1G, same as how you are at -1G at the apex of a strong airtime hill. But there is a huge difference between rotating along a near-horizontal to reach the -1G point versus the upward acceleration and deceleration upon cresting the hill to reach the -1G point.

[rcjp]

It's the same thing, but I bet you want to experience -1G on a roller coaster instead of hanging yourself upside down, right?

True. That's also why I'm generally not a big fan of hangtime but love airtime. Even though they're both negative Gs there's nothing special about being suspended upside down while going over a hill and being pulled up feels way cooler.

[KingRCT3]

This discussion is actually very exciting, and I'll try to contribute. Sorry in advance for my english.

 

A first simplification you're all doing there that is misleading for understanding all of that, is considering that the heartline is perfectly centered on our body. It's not, because you either seat on the right or left seat (except if you're riding Thunderbolt at Luna Pak ). Which is why in a transition à la Maverick from right bank to left bank, you'll either feel airtime and laterals to the left on the left seat, or positive and laterals to the right on the right seat.

 

Then for the difference between -1g on a camel back and -1g hanging upside-down, well I'd say it's due to our inner ear and our knowledge on which way is up, which way it's down that makes us feel those two in a different manner.

It's the same thing as 1g lateral is painful on a wild-mouse (or at least noticeable), while it's not bothering in a heartline-roll. You do have 1g lateral when you're at 90°. But it's more natural, since it's toward the ground, than the laterals on a wild-mouse.

 

Same things apply for very strong positives. I find them enjoying while being in a valley -I'd expect that- than where it's at the top of a tight loop where it feels very unnatural.

 

As for the question of a sideway loop, AKA can we lean a track to 90° and feel only positives forces? No, no and no! No because the gravity is still there. And if your turn is flat, it's still pulling you down with a force of 1g.

So you can have 5g horizontal thanks to the radius of the curve and the speed of the train, you'll still have 1g vertical. When you sum up the forces, it makes a square triangle where the resulting force is the hypotenuse -> It's angled!

 

The only way to counter that is either to reduce the banking, so it's kinda like creating a lateral force that will counterbalance with the gravity, or you apply a vertical translation to your track that will follow a parabola.

Edited May 31, 2015 by KingRCT3

[RMC_Hoodie]

^Negative or Zero Gs.

 

The momentum is moving vertical, against the force of gravity. It only seems lateral due to it being 90* banked; therefore pushing riders to their side instead of the usual upwards "out of your seat" sensation.

 

By that logic, wouldn't being pushed into your seat at the top of a tight loop be negative g's? And going through a sideways helix be lateral g's? We're talking about forces exerted on the rider.

[buck funny]

By that logic, wouldn't being pushed into your seat at the top of a tight loop be negative g's?

 

depends on frame of reference. from the point of the rider, you are being pulled down towards the track because the centrifugal forces from the loop are greater than the force of gravity (trying to pull you away from the track when you are at the top of the loop) so it is a net pull towards the track.

 

Your friend on the ground watching sees you being pulled up away from the ground as he has a different frame of reference (assuming he is standing upright still).

 

the clothoid loop enters with a gentler curve (larger radius) and therefore lower normal g forces pulling you towards the track because at the bottom it is adding to the earth's gravity. once your train goes beyond vertical the centrifugal forces are now working against gravity. the radius tightens to make more g forces to compensate for earth's gravity trying to pull you out of your seat away from the track.

 

on top of that, you go faster at the bottom and slow down as you go higher at the top. centrifugal forces are proportional to velocity and radius of curve.

 

With a bit of math you can make the normal forces on the rider constant throughout the loop by altering the radius from large at the bottom to small and then going large again as you pull out. Loops tend to look like cursive 'l's We have mr stengel to thank for working that out.