Originally posted by Tyler
What are these ASTM standards your're quoting?
What are these ASTM standards your're quoting?
The following measurements are from ASTM amusement ride standards. I can't find any mention of coaster types just yet, but there is a general overview of allowable G-forces.
The "at # sec" means for that amount of time, like "at 2 sec" means a certain level of G's sustained for 2 seconds.
Lateral: Under 1 sec +/- 3.0 G's
At 1.5 sec +/- 2.5 G's
2.0 sec + +/- 2.0 G's
Looks like we have been overly strict on that front. Again, I am not sure how each coaster type relates to these numbers and how they are restricted, but this is raw data.
Airtime: At 0.2 sec -2.0 G's
0.5 to 4.0 sec -1.5 G's
7.0 sec + -1.1 G's
Pretty impressive. However, wooden coasters are capped at -1.3... I couldn't find it in these standards (there may be more standards as well that I haven't found yet) but since PTC said -1.3, we can assume that -1.3 is a cap on wooden coaster airtime.
Now, it starts to get complicated.
The following are G-force rules that apply to transitions from lateral or other positive vertical G's, or less than three seconds of negative vertical G's.
Positive G's: Under 1 sec +6.0 G's
At 1.5 sec +5.0 G's
2.0 to 4.0 sec +4.0 G's
5.0 to 11.8 sec +3.0 G's
12.0 sec + + 2.0 G's
The following are G-force rules that apply to transitions from 3 seconds or more of negative vertical G's
Positive G's: Under 1.5 sec +5.0 G's
At 2.0 sec +4.0 G's
2.5 to 6.0 sec +2.0 G's
So transitions from airtime to vertical G's have to be done carefully.
The maximum allowable G's in a coaster is 6.0 G's by the standards.
The G's get tweaked a bunch (usually lessened) depending on the ride type - wooden coasters have one set of rules, suspended coasters another, looping coasters another.... these have to be found out by asking manufacturers, which I don't have time to do right now. But the standards above are a good starting point.
Quoted directly from: http://coasters2k.com/forums/viewtopic.php?t=3087