Is negative 2 G's reasonable?

[Goku1910]

I created a coaster in Newton, but as usual, the speed between the Netwon program and the Simulator is slightly different....meaning that my negative G's get over a 2. Think that's reasonable or do I need to rebuild the track?

http://www.reviewjournal.com/lvrj_home/ ... 13554.html

^Some in the article I found are even higher.

Rebuild the track... Also, that study isn't accurate. Look at the last one:

1. Desperado, Buffalo Bill's

Overall G-Rating: 24.06

Front/back Gs: +3.42/-3.94

Left/right Gs: +4.55/-5.25

Up/down Gs: +2.8/-4.1

That's not right...

[Turbo]

I have a feeling that the G's described in the article are inaccurate.

[Goku1910]

I'll see if I can trim in somewhere, the track is a layout I'd like to keep. I know how we all hate trim brakes but....

I think -2 is probably a bit much. What type of coaster are you building, anyway?

Those readings were probably measured, but I'd guess they were peak/noise. Sustain is more important than the number. You pull hundreds of Gs jumping on a trampoline but it isn't sustained. That said, the realistic approach to NL is to keep the number low but the attack quick. In real life, most of what is considered ejector is usually close to 0, but you are going from positive to negative so quickly that it feels much stronger.

[Goku1910]

That I'm not revealing yet, but now that I got Turbos input, I'm sure it's way too much for the type.

This isn't a Vekoma [^]

[Goku1910]

I trimmed the two fastest hills. Now the G's don't exceed -1.4 which is n't perfect but it's not 2.1 like it was before.

-1.4 seems reasonable for certain manufacturers. *cough*Intamin*cough cough*

Skyrush hit -2.0 before the trims, but even with the trims its still way out there

How is there such a drastic discrepancy between Newton and NL? You could first start off by revealing your intended force; what you plugged into Newton. And then account for differences appropriately. For instance, next time, keep in mind that the train's front and back ends will probably pull more than what you plugged into Newton. You say that you dip under -2.0 g's because of the Newton/NL speed difference? I can't imagine that there would be a very severe deviation which leads me to believe you shot for -1.6 or -1.7 perhaps? Plan ahead!

[Goku1910]

I looked into newton again and I see what might have caused the problem....I found no negative G input at all on the first hill and the second had a slight negative but nothing big (-0.5).

But I think I know what's causing it. The curved geometry at the top of the lift is set to manual until it's over the crest of the hill, so Newton thinks the train is going slower as it leaves the lift than it really is. Unfortunately it will be very difficult to fix without redoing the entire ride.

The worker must be smarter than the tool.

What ^he's^ trying to say is, when you plug a value into Newton, that is the approximate value of the g's that the MIDDLE car will experience. The front and back will have stronger forces because they're traveling at a slightly different speed at that point in the track compared to what the middle car will be traveling once it reaches that point. So instead of putting in -1.5, put in -0.8 to -1.0ish.

Originally posted by tiepilot35

when you plug a value into Newton, that is the approximate value of the g's that the MIDDLE car will experience.

Actually, Newton calculates the forces and speed based on only one car. If you have more than one car in your train, the forces will be slightly different because there's more momentum coming from the back of the train.

[Goku1910]

Again, the problem was that I used a curved geometry That ends with a manual speed.

See:



I also know that the friction value counts too, I made a slight adjustment and now the speed between the Sim and newton is near the same....but that's only if I turn off the improved friction.

If anyone knows to calculate the friction value, please PM me. The one I'm using now isn't accurate for the # of cars I have,

This is a simple fix. Make the top of that lift segment into more parts. The chain releases around -15 degrees. So, back that curved part up to -15 with the lift speed as your exit speed. Then just put another curved piece in for the rest of that crest into the single/multi segment.

[Goku1910]

I've already done that but it's impossible to fix my other version of the ride. Right now I'm on the third iteration of the said ride.

The only way to fix the second iteration is by trimming it because editing the lift in any way causes Newton to throw a fit in the other section(s) after it. As for the first version of the ride, you don't want to know.

Well, that's the simplest solution for you. Either fix the lift and fix the rest of the ride, or put a trim in there.

-2 is of course a lot, but as long it doesn't last for too long it's no problem. When I jumped from verzasca dam, I think the g force must've been close to 2 for more than 1 second.