Lukich Posted December 1, 2005 Share Posted December 1, 2005 So I have put together this little network where i'm dropping a ball onto a cloth. I wanted the ball to roll on the cloth, but even though they rbd and the cloth react to each other, the ball flies through the cloth. do you guys know what i'm doing wrong? thanks a lot, Luka cloth_collision.rar Quote Link to comment Share on other sites More sharing options...
deecue Posted December 1, 2005 Share Posted December 1, 2005 hey lukich, i didn't check out your file yet but there is an example file in the cloth solver that does just this (balls dropping on constrained cloth).. maybe that might point you in the right direction.. Quote Link to comment Share on other sites More sharing options...
michael Posted December 1, 2005 Share Posted December 1, 2005 your sphere is really really heavy...put the density down to 1 and it will not go through the cloth..... I'm really not liking the defaults in DOPs....if the units are metric - mass of 1 = 1 liter of water...the default RBD object is really massive when doing simple little tests... Quote Link to comment Share on other sites More sharing options...
deecue Posted December 1, 2005 Share Posted December 1, 2005 yea, defaults are really heavy.. they even note this in the dops quickstart or somewhere like that. you kind of need insane forces in order to keep up with the defaults (just try any kind of spring constraint).. don't know where the decision came from but a density of 1000 seems kind of over the top. that's usually the first thing i set before going ahead with anything else. Quote Link to comment Share on other sites More sharing options...
Lukich Posted December 1, 2005 Author Share Posted December 1, 2005 Thank you, guys, I'll see into it. Also, I'd like to add my two centavos about the values in DOPs - on an RBD glue object, if I want the glue to hold for even a little bit, I had to crank the internal glue value all the way to 10000, everything else left at defaults. Or maybe I'm doing something wrong again? Quote Link to comment Share on other sites More sharing options...
michael Posted December 1, 2005 Share Posted December 1, 2005 yeah....it's because everything is so damn heavy...lots of energy whizing around...you'll need very high values to counteract those forces.... Quote Link to comment Share on other sites More sharing options...
Mario Marengo Posted December 2, 2005 Share Posted December 2, 2005 I mentioned the "glue threshold" problem back in beta-testing days, and Jeff Lait gave a nice explanation of *why* it happens, though I still think it should be expressed as a fraction of composite mass. At that point there was an RFE to enable one to fetch the composite mass ( using a dopfield() expression wasn't working back then) and so be able to set up the relationship by hand. Has anyone checked whether we can get an accurate measure of composite mass (the object's total aggregate mass) when the creator object is set to "Calculate Mass" automatically? (I haven't been using DOPs lately so I haven't checked). Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.