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(OP)
Hello,
I´m new here, so i try to describe my problem as good as possible. My problem is that i have to simulate RC car chassis on my school project. I only have adams/view and i´m using PAC2002 tire model. On each wheel i get rotational joint motion with velocity formula using STEP5 function: STEP5(TIME, 1,10/0.03, 4,5/0.03).
The initial conditions have to be 10 m/s. Unloaded radius is 0.03 m. I don´t know how to make a bigger friction cause everytime there is a big longitudial slip and velocity for example of baterry is in 5 sec only about 9,1 m/s.
Could someone tell me what i´m doing bad? Is there any other solution have to brake the car using Adams/view?
Thanks for all help, cause i´m starting to be hopeless.
Sorry for my english.

Do you understand what you have written in the STEP5 statement? I assume that is for the rotational velocity of the wheel?

That's not really a very good way of braking a wheel, real brakes apply torques.

However, more likely you haven't switched friction on between the wheels and the ground.

Click contact, select a wheel, select the ground. Then switch friction on and set it to 1.

There are many other problems with what you are trying to do, I suspect.

Incidentally I strongly suggest you do the Latch tutorial in the getting started guide.

Cheers

Greg Locock

New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies  http://eng-tips.com/market.cfm?

(OP)
I think that when I use tire and road i don´t need applying contact on it. So I´ll try it when i get to the work PC.

Also I try the Latch tutorial as you say. How can I apply torque when the step function is not the best way to do it. Sorry for my question.
Thank you for help

(OP)
When I try to apply contact (Solid 2 Solid) between the wheel and road i get this error when I start simulation.

WARNING: The shell file 'C:/Users/Home/AppData/Local/Temp/avw10.shl' could not be opened for input.
Using a temporary exported version of the file.
ERROR:   The CM marker for Graphic External  ID = 149 is undefined.
Marker ID = 254.
ERROR:   Model did not pass verification phase.

(OP)
that works well :( so there is a problem in my model..but i´m still not sure if I have to apply contact between Tire a Road. I think that its included in this function already.

(OP)
So now everything I need is to find something where I can apply bigger friction between this two parts (tire & road). But I cant find the friction parameter in tir file of pac2002

You can either read up on how a pacejka model works, in the tire manual, or perhaps more likely is find out what else is wrong with your model.

If the tir file is from  a real tire it probably has enough friction already.

Cheers

Greg Locock

New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies  http://eng-tips.com/market.cfm?

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