Longitudinal slip exceeds the validity range

Question

Hi,

I had tried to model two-wheelers for a month, and I have made the model which is quite interesting, and Adams's view has no problems to simulate it and works fine. I have used tire model 'pac_mc_120_70R17_cross.tir' for both front and rear wheel where road profile is '3d_bump.rdf'. But the problem that I am currently facing is a warning message in the message window. It says, Long. slip exceeds validity range. And also the front wheel has no rotation motion at all. But If I remove the motorcycle chain, the front wheel will begin to rotate as the bike moves forward. Is there something that I missed because I don't have much experience in ADAMS.

Jesper Slattengren · Accepted Answer

Those are mass properties. The ONLY thing where ADAMS cares about area is for beam elements.

Now open your tire property file "pac_mc_120_70R17_cross.tir" in a text editor (well, make a copy of it first to your working or private cdb). Then locate the [DIMENSION] block and look at the parameters in that block.

[DIMENSION]

UNLOADED_RADIUS = 0.306 $Free tyre radius

WIDTH = 0.120 $Nominal section width of the tyre

ASPECT_RATIO = 0.70 $Nominal aspect ratio

RIM_RADIUS = 0.216 $Nominal rim radius

RIM_WIDTH = 0.15 $Rim width ??

Change those, sav the file and point the tire to it. As long as there is no imported geometry for the tire, it should update now.