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curve-entry speed of AI traffic
Posted: Wed Mar 12, 2003 5:27 pm
by gooneebird
Please help me!
I notice that my AI traffic slow down to approximately 70MPH to enter either 1500r or 2000r curves, within a 20-mile section of track I’ve laid that has no pointwork and where the speed limit is set to 125MPH. James Hunt's brilliant, speedy HST is one such train-type of my AI traffic. Might I have somehow mislaid track such that AIs slow so much? Does everybody’s AIs slow this much? Lastly, can AI-traffic curve-entry speeds be raised?
Thanks

Posted: Wed Mar 12, 2003 7:08 pm
by JohnEyres
Strangly enough I have noticed this. I was suprised when I set up my first AI train a while back that it slowed over pointwork. Although this is prototypical I was suprised it slowed when the speed limit was 100mph. Also some tighter curves also definatly slow down AI trains for some reason. Like above, its probably prototypical in most cases that a train would slow down for pointwork or tight curves instead of clattering over them at top speed. Don't know how the limit is set to different pieces of track though.
Posted: Wed Mar 12, 2003 7:53 pm
by gooneebird
JohnEyres wrote:...it slowed over pointwork. ..//.. Also some tighter curves also definatly slow down AI trains for some reason. Like above, its probably prototypical in most cases that a train would slow down for pointwork or tight curves instead of clattering over them at top speed.
Hmm, I can understand AIs being programmed to slow just a
little for broad-enough curves, but to 70MPH seems overkill to me. I wonder if AIs slow even more for 2_5r points. Do you/Does anybody know if AIs slow just as much to enter 4000r and 15000r curves of X Tracks, coz maybe it's altogether a 'curve tag' in MSTS that causes AIs to slow so much?
Thanks
Posted: Wed Mar 12, 2003 9:40 pm
by jashton
The intrepid Stuart Williamson found a discussion on this item...
http://forums.atomic-systems.com/viewtopic.php?t=12868
Jeff
Posted: Wed Mar 12, 2003 9:58 pm
by gooneebird
Thank you! big time. Very useful info in that second, hyperlinked post (msg #15).
Posted: Thu Mar 13, 2003 9:16 pm
by kevarc
Light bulb just went on on this. MSTS does not have superelevation on curves. Therefore to make the curves it has to slow down further.
Posted: Fri Mar 14, 2003 6:02 pm
by gooneebird
kevarc wrote:Light bulb just went on on this. MSTS does not have superelevation on curves. Therefore to make the curves it has to slow down further.
A message sub-hyperlinked in either of the two messages above discusses augmenting:
* the "DerailRailForce" amounts found in the wagon files and wagon portion of the engine file(s) to all the units comprising the consist;
* the maximum velocity portion of the tag -- which I can't quote here right now -- found toward the top of the consist file; and
* the value of the 'something-something CriticalLevel' tag ought to reflect the 'maximum velocity' tag within the engine portion of the engine file, but I've a hunch doing so with this one isn't necessary.
Well, it seems I bumped up the "DerailRailForce" too high, coz my AI consist both accelerated and decelerated too rapid (respectively from and to zero MPH), although the train didn't slow much for either curves or points. So I returned the maximum-velocity portion of that consist tag to its original value without altering the new "DerailRailForce" value, and my AI consist still took on curves and points at just as high speeds, plus it still accelerated and decelerated too swift on curves and pointsto.
Maybe the values of the 'MaxTilt' tag in the wagon files and wagon portion of the engine file(s) are the attributes that ought to be fiddled with to avoid causing too rapid an acceleration/deceleration from/to 0MPH?
I'll post another message should I get any closer to making the AI perform more realistically.
Thanks
Posted: Mon Jan 05, 2004 6:18 pm
by gooneebird
Well, I haven't gotten any closer to improving AI performance on curves and hills.
kevarc wrote:MSTS does not have superelevation on curves.
I was trying to tackle this matter of trains slowing down for curves, etc., over the holidays, because (in ITR mode) one of my DerailRailForce-tweaked trains was slowing too much for a
sloping curve.
However, I came across that "MaxTilt" (sp?) parameter again. Do you/does anybody know of a wagon or engine that activates this parameter? I couldn't find such an example from a bunch of my engine/wagon files, and I'd feel more comfortable seeing such an example being activated before trying to induce it myself. For instance, what units does that field/parameter use; can it be higher than one; is it integer in value?
Cheers,
gooneebird
"Prochaine station: Cadillac."
http://www.geocities.com/BourbonStreet/Bayou/4804/ a fictitious network serving London, Weymouth, and points in between.
Posted: Mon Jan 05, 2004 9:47 pm
by baldwin
I dont know of one. There are quite a few parameters laying around that apparently have no function, at least, no-one has got a result when trying them. The only way to find out if this one works is "give 'er a whirl".
Mervyn
AI traffic speed
Posted: Mon Jan 05, 2004 10:11 pm
by lemberg
Hi Lemberg here, tried that mod in the consist files and now have better speeds from different loco's. Don't have class 37's accellerating away faster than 125's, HOORAY!.
