Hi IPG Team,
I am working on recreating our FSE AWD car from last season in CarMaker 14.1.1. We previously used versions 10–12, but the model was not fully complete. Because of this, I started rebuilding the car based on the FSE AWD model included in the FS LTS Package provided with CM 14.1.1.
So far, I have entered all of our trim loads, body parameters, and powertrain loads as accurately as possible based on our logged data. For the kinematics, aerodynamics, and powertrain, I reused the latest model we had from previous seasons.
When I started training the IPG Driver, I noticed that the car was driving extremely slowly on the track. I suspected a vehicle dynamics issue, so I tested the car myself using a racing simulator wheel. The car is unstable and becomes unmanageable at corner-entry speeds above 50 km/h, often rolling over. Additionally, the regenerative braking system is not behaving as expected—the car does not slow down properly when the brakes are applied. I have tried adjusting many parameters to compensate for what appears to be an incorrectly modeled car, but nothing has resolved the issue.
At this point, I am unsure what I may be doing wrong in the modeling process. Could you please guide me on which specific parameters or areas I should review or tune to resolve these vehicle dynamics issues in the simulator?
Thank you very much for your help.
Hello @Candrnk_Rennteam ,
this seems like an issue in some parameters. Could you send the question again with the vehicle model (ideally also the project directory so that all the dependencies are taken care of) to our Formula Student Support forum? I have attached the link below. We will get back to you as soon as we can. Thanks!
Hello @ruthik.konnur ,@Candrnk_Rennteam
I am curious to know if you figured out the model problem. If so, could you share which parameters with incorrect values were causing the issue?
Thanks!
Hello @Candrnk_Rennteam ,
is it regarding the same issue, for which we had answered via e-mail ? I assume so.
Anyways, let me again post here the response, so there is any guidance to this thread.
On converting the .kin you sent earlier, I suspect the issue is pointing to the stabilizer. I noticed that with your kinematics file, the length of stabilizer is decreasing with wheel compression, similar to springs or dampers, as :
Actually the length of stabilizers will be expected to change opposite to how springs or dampers change, as:
You can refer the reference manual for the calculation of stabilizer or other force elements.
One quick approach can be carried in skc file itself, by changing the factor for stabilizer length due to kinematics, but make sure to verify the mapping of stabi against wheel compression, because this approach will only change the direction. Or you may want to change the fixing of stabi inside the .kin file before conversion to .skc.
I have used the Model Check tool here to plot the suspension results. It can be found under Main GUI > Simulation.
@moraveji had you faced similar issue, and did this help in improving your vehicle model ?
Let us know if this helps.
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@Parth.Patel Thanks for sharing the information how to debug. My model runs as expected; however, the roll behavior seems to be inaccurate. When I compare my model roll center height (SPMM mode) to the actual measured vehicle, they do not match. I will use your tip to see if that is the bug or not. Thank you very much again.
