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ADAMS Full car Dynamic analysis error // Steering-controller issue?

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Tanmay_Panchal

Automotive
Nov 13, 2019
5
Hi everyone,

This can be considered as a followup on my last thread : HERE

Big shout-out to GregLocock for patiently helping the forums if you are reading this.

Anyways, apart from last development on templates. I was also able to solve the car pulling issue, apparently it was due to some incompatible tyre models which I changed. It seems newer 2018 ADAMS doesn't like if you just copy and paste old 2014 worked files. In the video below, one can see I was finally able to refine the model and even add graphics.

Link


So now I am able to run all the open loop steering control events. By open loop I mean events which are governed without any feedback from the events itself (like J turn, double lane change with maximum radius path, straight line acceleration, braking, maintain, etc...).

Only two creases are still left. I am not able to run any closed loop events. Events like double lane change with Default controller and 3D road, as well as skidpad holds which also takes feedback from events manipulating the throttle brake and steering demands. Looking at the messages it seems like there is some sort of PID control coded to make this happen, this is what is causing my model to give the error of lockup.

I am enclosing an image of a typical setup of DLC with just default controller (which crashes, crash file messages also enclosed as txt) and same DLC run with Max Radius path controller, running fine as shown in video.


It would be great if you guys can point me where to look, I am looking at DCF and DCD files but they are also not giving me much clues to start with. Besides it works if there is no sort of feedback but crashes immediately with feedback. In-fact if I apply straight line control to steering for maintain, it crashes because again it is taking some sort of feedback to keep the car straight.

I wish to understand the implementation of this control and how it can possible affect my simulation?

Goal is to make a universal FSAE template which can run any 3d course or follow path like the Ferrari model in there.

1_tonmpp.png





 
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Yes, I don't use ADAMS for closed loop, as we have better proprietary driver models available elsewhere -our objective is to have realistic drivers, not ones that follow a given course by whatever means.

So you are saying the Ferrari will run the closed loops sims?


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Hey Greg,

Yeah, I was able to run the inbuilt Testarossa on hold radius maneuver like a skid pad event and give a 180 degree steering as the end criteria. Same maneuver couldn't be handled in my FSAE car.

Now that you have asked, I am curious. I will update if I am able to run the same on a 3D course to see if it can handle full sim.

 
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