Overlapping

eyore · Post by **eyore** » Mon Nov 28, 2005 10:37 pm

The buffers of the wagon I'm working on, overlap under braking.

I've used BBoxedit to check parameters and tried adjusting various values in the wag file coupling settings(stiffness, r0 values), without success.

Could someone point me in the right direction for which parameter I need to adjust to resolve the problem?

Phil

supergoods · Post by **supergoods** » Tue Nov 29, 2005 12:02 am

Try adjusting the length of the vehicle, the correct length I have found is the length over the body, not including the buffers.

The buffers of an unfitted waggon are 18" from the bufferbeam, for a fitted waggon the distance is 21"

After you have done this, try in a train and see the result.

The following is the .wag file for an unfitted 24.5T mineral waggon

Wagon ( BR_Diag_115_L
Id ( ? )
Type ( Freight )
comment( BR 24.5 Ton Mineral Wagon unfitted to Diagram No 1/115. 2,150 built 1953-56. Loaded)
WagonShape ( BR_Diag_115_L.s )
Size ( 2.64m 2.76m 7.71m )
CentreOfGravity ( 0m 1.6m 0m )
Mass ( 31.78t )
InertiaTensor ( Box (2.64m 2.76m 7.21m) )
Coupling (
Type ( Chain )
Spring (
Stiffness ( 1e1N/m 2e6N/m )
Damping ( 1e6N/m/s 1e6N/m/s )
Break ( 3.2e7N 3.2e7N )
r0 ( 10cm 15cm )
)
Velocity ( 0.1m/s )
)
Coupling (
Type ( Chain )
Spring (
Stiffness ( 1e1N/m 2e6N/m )
Damping ( 1e6N/m/s 1e6N/m/s )
Break ( 3.2e7N 3.2e7N )
r0 ( 15cm 10cm )
)
Velocity ( -0.1m/s )
)
Buffers (
Spring (
Stiffness ( 5.6e6N/m 5.6e6N/m )
Damping ( 1.1e6N/m/s 1.1e6N/m/s )
r0 ( 0m 1e9 )
)
Centre ( 1.5 )
Radius ( 1 )
Angle ( 2.5 )
)
BrakeEquipmentType( "Handbrake, vacuum_brake" )
BrakeSystemType ( "Vacuum_piped" )
MaxBrakeForce ( 0N )
MaxHandbrakeForce( 31780N )
NumberOfHandbrakeLeverSteps( 100 )

Adheasion ( 0.2 0.4 2 0 )
DerailRailHeight ( 4cm )
DerailRailForce ( 85.806kN )
DerailBufferForce ( 90.89kN )
WheelRadius ( 0.476m )
NumWheels ( 1 )
Friction (
469.4N/m/s -0.11 5mph 2.787N/m/s 1.744
5.1N/rad/s 1 -1rad/s 0 1
)

Sound ("..\\..\\common.sound\\unfittedwagon\\unfittedwagon.sms" )
)

This works well and has the correct run in and out as the train stretches and compresses

Ian

eyore · Post by **eyore** » Tue Nov 29, 2005 8:21 pm

Thanks for your help.

I'll give it a try and let you know the results.

Phil

eyore · Post by **eyore** » Wed Nov 30, 2005 8:12 am

Sorry, that didnt solve it!

Back to the drawing board.

Phil

ianmacmillan · Post by **ianmacmillan** » Wed Nov 30, 2005 12:49 pm

The amount of space given to a wagon is set by the Size line in the wag file.

The numbers are width, hight, length.

Increase the last number in 0.1 steps until the buffer heads are slightly apart.

You will the have to adjust the bounding box length. Make the 3rd and 6th number slightly less than half the size length. Remember to add the minus - to the 3rd number.

eyore · Post by **eyore** » Wed Nov 30, 2005 6:48 pm

Ian

Thanks for trying to help.

As mentioned I am using BBoxedit to check the size etc, however, I thought I'd try your suggestion of incrementing length to see what would happen.

I now have a length parameter > actual size(including buffers) and still getting overlap of the buffers under braking

Phil

jbilton · Post by **jbilton** » Wed Nov 30, 2005 7:02 pm

Hi
I'm afraid to say I've found similar....unless the couplings are made ridged...is it an msts bug I wonder?
Cheers
Jon

dforrest · Post by **dforrest** » Wed Nov 30, 2005 9:41 pm

eyore wrote:Sorry, that didnt solve it!

Back to the drawing board.

Phil

e-mail me the .wag file(s) and let me try something.

.

eyore · Post by **eyore** » Thu Dec 01, 2005 12:59 pm

Jon

Following your post I looked at some other chain coupled wagons and found a similar problem.

Perhaps it is a MSTS bug, or do I just have to try harder to find the solution?

Phil

supergoods · Post by **supergoods** » Thu Dec 01, 2005 1:27 pm

I lost the logic behind what I did a couple of years ago and the dia 115 .wag file is all that survives.

I know it was trial & error, but once you find the right combo of parameters the result is very effective.

What I may do is download the original dia 115 file again and see what I can deduce from the original and final versions.

Ian

jascott · Post by **jascott** » Thu Dec 01, 2005 8:45 pm

This might help

http://steam4me.railpage.org.au/trainsi ... ength.html

John

eyore · Post by **eyore** » Sun Dec 04, 2005 3:34 pm

Firstly, thanks to everyone who has tried to help with this problem of overlapping buffers, either on the thread or by direct contact. Regretfully, still not resolved.

Whilst experimenting with some settings on the wagon I happened to have the bounding box displayed and noticed that the buffers would overlap upto the point when the bounding boxes touched!

So I wondered if, contrary to all good advice, I should extend the bounding box to the end of the buffer, or even beyond? With the following strange result...

In SFV bounding box clearly beyond the end of the buffers, but

in MSTS bounding box well short of the end of the buffers.

As a newbie to stock creation I was already confused by the physics, but now I feel I've totally lost the plot.

Is this yet another "known" MSTS bug, and what to do?

Phil

1crick14a · Post by **1crick14a** » Sun Dec 04, 2005 5:12 pm

Below is what I'm using on a tender and passenger cars if I remove
the Rigid line I get overlapping on coupling and braking with it in the
connection is perfect

Coupling (
Type ( Chain )
Spring (
Stiffness ( 1e5N/m 5eN/m )
Damping ( 3e6N/m 5e6N/m/s )
Break ( 2.2e6N 5.2e6N )
r0 ( 0m 0.01m)
)
CouplingHasRigidConnection (1)
Velocity ( 0.1m/s )
)
Coupling (
Type ( Bar )
Spring (
Stiffness ( 1e5N/m 5eN/m )
Damping ( 3e6N/m 5e6N/m/s )
Break ( 2.2e6N 2.2e6N )
r0 ( 0m 0.01m )
CouplingHasRigidConnection (1)
)
Velocity ( -0.1m/s )
)
Buffers (
Spring (
Stiffness ( 1e5N/m 5eN/m )
Damping ( 3e6N/m 5e6N/m/s )
r0 ( 0m 0.01m )
)
Centre ( 1.5 )
Radius ( 1 )
Angle ( 2.5deg )
)

Now this is the settings I'm using for loose coupled trains I want to shunt around there is no overlapping here either but as I have read the couplings must be the same thoughout your stock I think what I'm saying here is much the same as anyone else it's a fiddle but it can be made to work............

Coupling (
Type ( Chain )
Spring (
Stiffness ( 1e1N/m 1e6N/m )
Damping ( 1e12N/m/s 1e7N/m/s )
Break ( 2.2e6N 2.2e6N )
r0 ( 0m 0.60m)
)
Velocity ( 0.1m/s )
)
Coupling (
Type ( Chain )
Spring (
Stiffness ( 1e1N/m 1e6N/m )
Damping ( 1e12N/m/s 1e7N/m/s )
Break ( 2.2e6N 2.2e6N )
r0 ( 0m 0.60m)
)
Velocity ( -0.1m/s )
)

Rick

eyore · Post by **eyore** » Mon Dec 05, 2005 10:48 am

Rick

I tried your settings (With and without rigid coupling) without success.

As before, the buffers overlap until the bounding boxes touch, as I think you can see in this image..

Its almost as if its ignoring the coupling.

Phil

AndiS · Post by **AndiS** » Fri Dec 09, 2005 10:50 pm

Have you made sure the following:
1. The length in Size in the .wag file is exactly the length from buffer to buffer. It is interesting that Shape File Manager shows the box bigger that just around the buffers.
2. The InertiaTensor is exactly the same as Size.
3. r0 (0m 0.05m) (second value not so important, first one very important in your case)

Then you could try:
4. Stiffness ( 1e6N/m 1e7N/m )
5. Damping (3e6N/m/s 9e6N/m/s)

I would also make the bounding box smaller by 10 or 20 cm on each side (only the length dimension of cource). It does not help the buffer overlap but it reduces the chance that they crash.

You could also PM me the .wag file, maybe I find something else there.