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angelah
January 13th, 2008, 02:54 PM
I am having problems with the swing and bascule bridges not turning or dropping soon enought for the approaching train which inevitably goes flying off into mid air. It does follow the invisible paths though and doesn't go crashing in the river. But it looks very odd.
Anybody got any ideas?

Angela

Ferrous
January 13th, 2008, 03:00 PM
Perhaps Ben Dorsey could tell you how to expand the trigger distance--my guess is the trains are going too fast to allow the bridge to lower in time (anything over about 45 mph would do that).

Ron_Smith
January 13th, 2008, 04:42 PM
I have used several of this type of bridge over the years and usually find slowing the approach speed to about 30Klms solves this problem. If you don't want to have speed signs showing - suggest using invisible ones.

Ron

bendorsey
January 13th, 2008, 05:18 PM
Hi ya'll:

The speed at which my interactive bridges open and close is determined when I setup the animation in Gmax. Its done in keyframes at 30 keyframes per second. Generally speaking the larger the bridge the more keyframes I use (300 kf = 10 seconds for small ones, 600 kf = 20 seconds for medium ones, and 900 kf = 30 seconds for large ones). As far as I know it can not be changed other then from within Gmax.

In the real world bridges do not open and close quickly. The stresses on the parts mandate slow movement. The larger the structure, the more it will resist a change in motion (inertia). Any attempt to change its motion too quickly will almost certainly strip the gears (or worse) and these aren't dinky little gears. Many are special order items.

So to all the speed demons, hot rodders, and potential Casey Joneses out there, your just gonna have to do a better job at resisting the urge to put the pedal to the metal, lol.

Ben:hehe:

TSwenson
January 13th, 2008, 05:52 PM
It would be highly prototypical to hare a slow order on a drawbridge of any sort. A reduction in speed when aproaching a draw or swing bridge is just plain safe. If for any reason there is a problem in aligning the bridge one would want to be able to stop before reaching the bridge. I recall a story about the draw bridge over the Cape Cod Canal, that the bridge failed to close corectly because someone had left a pair of workgloves in the way. Most safety rules for railroads are there because something bad happened, be it personal injury, property damage, or both.

bendorsey
January 13th, 2008, 06:10 PM
As far as I know all moveable bridges are wired to show when they are not fully closed and signal a train to stop. The problem is this is done through the rails so if the rails aren't broken the signal says everything is ok even though the rails may be bent and cause a disaster (which happened a few years ago over a bayou in Louisianna). Major train wreck.

My moveable bridges are done as mocrossings to take advantage of the built in triggering and script in Trainz. The disadvantage is the trigger radius is fixed at about 250 meters (I think) and can't be changed.

Ya'll just gonna have to slow down (or play Evel Kinevel and jump the open span on the invisible track), lol.

Ben

gfisher
January 13th, 2008, 07:08 PM
The question though, Ben, is not the speed with which your bridges open or close, which looks quite good, or even a tad fast to me. The question is whether there is a way to extend the trigger radius so that the bridge begins to move when the train is further away from it.

Ferrous
January 13th, 2008, 07:18 PM
As far as I know all moveable bridges are wired to show when they are not fully closed and signal a train to stop. The problem is this is done through the rails so if the rails aren't broken the signal says everything is ok even though the rails may be bent and cause a disaster (which happened a few years ago over a bayou in Louisianna). Major train wreck.

I think you're thinking of the Big Bayou Canot Disaster (http://en.wikipedia.org/wiki/Big_Bayou_Canot_train_disaster), which was a little closer to home.

martinvk
January 13th, 2008, 09:28 PM
The question though, Ben, is not the speed with which your bridges open or close, which looks quite good, or even a tad fast to me. The question is whether there is a way to extend the trigger radius so that the bridge begins to move when the train is further away from it.

For that I think you would have to work with scripts. Using the mocrossing like I also did means you have to live with a fixed trigger radius. So everyone will just have to slow down and give the bridge time to close. :wave:

angelah
January 14th, 2008, 05:59 AM
The question though, Ben, is not the speed with which your bridges open or close, which looks quite good, or even a tad fast to me. The question is whether there is a way to extend the trigger radius so that the bridge begins to move when the train is further away from it.

I agree, the movement speed is excellent, the problem is with distances. I know from watching level crossings work on the real railways that they close long before a train is due.
The speed at which I tested this on a new route is from 75 down to 40 at 1000 feet from the bridge.
The span starts its turn when the from of the train is only 328 feet from the bridge, now that's blinking close in anybody's book....

So the train is NOT doing an excessive speed as everybody seems to assume and the speed of operation of the bridge is NOT an issue, as some have also assumed.

At under 40 mph (the train is set to that but as we all know they run under speed so actual speed is 37) the bridge barely makes it closed as the train enters. In reality that is cutting it very fine - too fine.
In MHO it's the activation trigger that needs extending out to about 1000 feet. This is a double track main line so I don't want to drop the speed too much if at all possible, 40mph would be ideal.

The whole thing revolves around the distance from the bridge and when it start to operate. 328 feet is damned close...

Angela

martinvk
January 14th, 2008, 07:40 AM
At this point, unless someone knows how to change the built-in trigger distance, you wait for the "next" version :'( or start work on a script. :cool:

bendorsey
January 14th, 2008, 08:17 AM
Hi All:

I agree the trigger is too close but as far as I know the trigger radius is built into Trainz and can only be changed by Auran.

If some kind and benevolent scripting guru would like to write one that would allow variable trigger radius I'd be glad to use it (as would others I'm certain).

Ben

angelah
January 14th, 2008, 09:13 AM
Hi All:

I agree the trigger is too close but as far as I know the trigger radius is built into Trainz and can only be changed by Auran.

If some kind and benevolent scripting guru would like to write one that would allow variable trigger radius I'd be glad to use it (as would others I'm certain).

Ben

Thanks Ben,
Your post clears the matter up. If somebody had said (in plain English that a mere blonde can understand!) I would have understood.
At 1000 feet and at 40 mph the swing bridge just abouts makes it...

Cheers,

Angela

bendorsey
January 14th, 2008, 09:39 AM
Hi Angelah:

If you think about it we are lucky they work at all. We are using something built into Trainz that was originally designed to raise and lower 20 or 30 ft long crossing gate arms in 5 seconds - - - not animate 600 ft long bridges in 30 seconds. The trigger radius they set is fine for a real mocrossing (motorcar crossing). You might say we are pushing the limit by using it for gigantic bridges so I guess we just have to accept the short-comings.

On the happier side, the method could be used for almost any animation one would like triggered by an approaching train. Rearing horses that don't like the loco, kids running toward the train because they want to watch it go by, folks waving, etc.

Ben

angelah
January 14th, 2008, 02:30 PM
Hi Angelah:

If you think about it we are lucky they work at all. We are using something built into Trainz that was originally designed to raise and lower 20 or 30 ft long crossing gate arms in 5 seconds - - - not animate 600 ft long bridges in 30 seconds. The trigger radius they set is fine for a real mocrossing (motorcar crossing). You might say we are pushing the limit by using it for gigantic bridges so I guess we just have to accept the short-comings.

On the happier side, the method could be used for almost any animation one would like triggered by an approaching train. Rearing horses that don't like the loco, kids running toward the train because they want to watch it go by, folks waving, etc.

Ben

I never meant to intimate it might be your fault, I just wondered if it was possible, that's all. I think creators do an amazing job so keepup the good work.
I got around it (just) by slowing the train to 40mph, it just makes it....

Things are running okay now.

Cheers,

Angela