Static equilibrium analysis has not been successful with parabolic road

M Mueller over 3 years ago

I get this error

“Static equilibrium analysis has not been successful.

The maximum number of iterations 25, has been reached”

when using parabolic road profile.

I have adjusted the car wheels exactly to the road, however with no improvement.

When I modify the initial part of the road to be flat the simulation runs without problem.

Can somebody advise me, what could help?

0 Rishikesh Mokashi over 3 years ago

Hi ,

Can you try running the simulation by first setting the environmental variable called "MSC_ADAMS_TIRE_GHOSTS=1" as described in this article:

https://simcompanion.mscsoftware.com/infocenter/index?page=content&id=KB8024774

This variable helps avoid unexpected static solutions on uneven road surfaces i.e. when the road surface is not flat beneath the vehicle (sloped or banked ramps or uneven roads).

You should also try and set the value of MAXIT under the solver settings ( settings>>solver>>equilibrium) and set its value to 250.

Please check if setting this variable solves the problem. The article above described how to set this variable.

I hope this helps.

Regards,

Rishi
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0 Alexis Del Rio over 3 years ago

in paralell to Rishikesh advice getting all tyres penetrating through the road is good practice, a few cm is sufficient
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0 jpatterson over 3 years ago

"a few cm"? Do you mean "mm"?
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0 Alexis Del Rio over 3 years ago

yup, I meant cm. I guess saying "few" is misleading. What I'm after is to actually see the tyres through the road. eg: the attached image penetration is a bit too far although it does the trick nicely
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0 M Mueller over 3 years ago

I modified the number of static iteration but it has not helped, however the MSC_ADAMS_TIRE_GHOSTS=1 helped so far, the simulation started. The problem now is that the car lost the road (it submerges into the road) when passing the curve. Could you advise me what to do with this problem?
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0 jpatterson over 3 years ago

Interesting. I'm in the habit/tradition of having them just touching. I'll give this a try.

Do the "Ghost Forces" help on flat roads, too? I'm currently wrestling with a full vehicle that refuse to solve statically.
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0 M Mueller over 3 years ago

I tested the solution on the flat road and it started without any problems. So, it was not necessary to switch the Ghost Forces on. But I have the same problem with the flat and parabolic road that the car submerges the road when passing the curve.
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0 M Mueller over 3 years ago

I also set a small tire intersection in both the cases.
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0 Alexis Del Rio over 3 years ago

with crg files I noticed a few times, thatrepositioning the vehicle in x or y helps achieving equil.
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