I have tried, since my last question, to set physics attributes to a car accident. Being one who wants to figure these things out myself, I have practically ignored the wealth of info available here.
Has anyone here re-created a medium speed auto accident using physics? I'm looking for a T-bone situation at 25 to 40 mph without a rollover, or, as I have found, the impacted car flies away while the suspect car stops dead.
What I'm asking for are starting attributes to keep the situation realistic. ie: both vehicles stay on the ground, skid to a stop, and no one dies. I've tried various combinations of gravity, density, velocity, bounce, and friction. What am I missing?

If I remember right from Eovia's past tech partners, the Havok physics engine that Carrara uses is from ca. 1998.

Half-Life 2 uses an updated Havok physics engine. I haven't played the game, so I don't know how it handles car wrecks (the newest version 3 of Havok does handle vehicle physics). I've seen it do some good ragdoll physics for human figures. Maybe Carrara 5 will get a license to use the new physics engine?

Message edited on: 08/24/2005 23:32

Actually, Carrara no longer uses the Havok physics engine. Something to do with licensing. Not sure what version of Carrara physics got replaced. But the current physics engine was written from scratch. That said. I'm not sure I completely understand what you mean wellspunweb by a t-bone situation. But the physics engine in Carrara does have limits. Its difficult to get an animation like vehicles rolling on the ground, you'll tend to get bouncing or as you said rolling. Is there a reason you are using physics? A specific result you are looking for? Brian

The game Car Wars had some decent rules for T-bone collisions. I'm guessing Carrara will have to be told how to move (decelerate) the vehicles manually and how to apply damage to them using similar rules.

Message edited on: 08/25/2005 01:38

Depending on the purpose of your experiment. You could create the necessary models in Carrara. And export to either of these: (game engines) http://www.otee.dk/index.html http://www.candointeractive.com/gamedesign/car/

I was under the incorrect assumption that physics generators followed natural physics laws. But then, I'm no programmer. Thank you everyone for the education. The only reason, Brian, for trying to use physics, is in predicting a result rather than creating one. But, creating a result is o.k. for most situations. Dean

Carrara (right now) has bouncing and spinning physics for hard objects. It doesn't do stress, fluid, or heat physics as far as I've seen. You can apply modifiers to your objects to fake any damage being done. Some modifiers are less cartoon-ish than others.

Message edited on: 08/25/2005 12:54

Attached Link: http://www.shonner.com/drafts/images/t_bone_crash_divx.avi

Message edited on: 08/26/2005 02:31

I got this far a while ago, the client was happy with it. Personally, I think I can do better. http://www.wellspunweb.com/crashtest.html I'll appreciate any feedback from anyone.