How to edit parameters of auto tire entity?

Sudip_Chavan

Hello Everyone,

I'm getting warnings during full vehicle simulation as mentioned below,

1. Vertical load is below tire file parameter FZMIN. It is capped at (100)

2. Inclination angle is above tire file maximum parameter CAMMAX. It is capped at (0.2)

3. Inclination angle is below tire file parameter CAMMIN. It is capped at (-0.2)

After these 3 warnings analysis fails saying, ERROR: Statics analysis failed at time = 0

Before ending overall file it gives following errors,

ERROR: Simulation failed due to error encountered in analysis!

Forced termination from API_SendOffCommandSimulate!

ALTAIR DRIVER : : Error running STATICS/Static

ERROR: Error encountered in processing xml input file!

 

I'm thinking about changing values of auto tire to get rid of warnings but it may not be the main concern causing failure in the simulation.

Please let me know if anybody can decode any specific issue in the model.

 

Thanks & Regards,

Sudip Chavan

 

GTT Adam

Sudip Chavan_20509 said:

Please find the attached log file below. 

 

Hi Sudip,

The LOG file unfortunately does not show what I expected. Does the message window show any information about errors?

You could also try a different simulation type to see if new errors are produced that may help you figure out what is wrong with the static setup.

 

Hope this helps!

Adam Reid

GTT Adam

Hi Sudip,

The auto tire warnings you are seeing are just warnings, as the validity range specified in the tire property file is being exceeded. For example, the following ranges are set in the property file:

$-------------------------------------------------vertical_force_range
[VERTICAL_FORCE_RANGE]
FZMIN                    = 100               $Minimum allowed wheel load         
FZMAX                    = 10000             $Maximum allowed wheel load         
$------------------------------------------------------long_slip_range
[LONG_SLIP_RANGE]
KPUMIN                   = -1.5              $Minimum valid wheel slip         
KPUMAX                   = 1.5               $Maximum valid wheel slip         
$-----------------------------------------------------slip_angle_range
[SLIP_ANGLE_RANGE]
ALPMIN                   = -1.5              $Minimum valid slip angle         
ALPMAX                   = 1.5               $Maximum valid slip angle         
$-----------------------------------------------inclination_slip_range
[INCLINATION_ANGLE_RANGE]
CAMMIN                   = -0.175            $Minimum valid camber angle         
CAMMAX                   = 0.175             $Maximum valid camber angle         

Therefore, if the vertical force on a tire ever goes below 100 N, it will trigger that warning.

 

The error message you are seeing is independent of the tire warnings.

The Static simulation you are trying to run fails due to an error found in the XML file. 

Please check the LOG file for more information by searching for ERROR.

It will likely show that there is an expression that is not being evaluated properly, or something along those lines.

If you upload the LOG file, we can likely help you find out what went wrong.

 

 

Hope this helps!

Adam Reid

Sudip_Chavan

Please find the attached log file below. 

 

GTT Adam

Sudip Chavan_20509 said:

Please find the attached log file below. 

 

Hi Sudip,

The LOG file unfortunately does not show what I expected. Does the message window show any information about errors?

You could also try a different simulation type to see if new errors are produced that may help you figure out what is wrong with the static setup.

 

Hope this helps!

Adam Reid

Sudip_Chavan

Adam Reid_21142 said:

Hi Sudip,

The LOG file unfortunately does not show what I expected. Does the message window show any information about errors?

You could also try a different simulation type to see if new errors are produced that may help you figure out what is wrong with the static setup.

 

Hope this helps!

Adam Reid

Hi Adam,

As of now message window doesn't show any errors.

I will try in different simulation types for new errors to figure out what is wrong with static setup and will let you know.

 

Thanks & Regards

Sudip Chavan

Angus

Hi,

I have a very similar error and I can not find any solutions. Did you manage to find one Supid ? I also tried different simulation scenarios but the errors stay the same. 

 

Best regards,

Angus Duff. 

GTT Adam

Angus said:

Hi,

I have a very similar error and I can not find any solutions. Did you manage to find one Supid ? I also tried different simulation scenarios but the errors stay the same. 

 

Best regards,

Angus Duff. 

Hi Angus,

Sudip had 2 separate issues earlier in this post:

1. Warnings were reported based on the valid ranges set in his tire file, which are just try alert the User that the tire files are operating outside of the valid range set by the User.
2. The static portion of his simulation was failing due to initialization issues with his vehicle model

If you are encountering failures within your driving events, I recommend that you isolate your vehicle from the driver model and event analyses to find any construction issues. Please try the following:

1. Make a copy of your MDL for this debugging process
2. In the copy, delete the Altair Driver and any events you had previously created.
3. Add a fixed joint from the vehicle chassis to ground
4. Run the Default Analysis as Transient for a few seconds with default global simulation settings.

Ideally, the vehicle will be held in place and the suspension will sag. Since there is no Static portion of the simulation, it should initialize and if there is anything significant happening that is causing the Static failure, you will likely see the issue. Make the correction in your full model, and then try the driving event again.

Please give that a try and let me know how it turns out.

 

Hope this helps!

Adam Reid