Using the simulation....

I started playing around with it the other day, you know something simple...ball dropping and rolling down a hill. Worked fine. Now when i changed the hill from just a stright line to one with say little bumps for the ball to roll over....well lets just say that it was a no go.
Does SW not use inertia in its calculations for simulation? If not, is that something for CosmosMotion or some other add-in?
And if I need to show a spring compress and expand because of weight, is that an add-in as well?
T.I.A.

"Arthur Y-S" wrote:
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that
SW uses inertia, but it does simulation in a very simplified way (and often gives surprising results) CosmosMotion and other "real" motion simulation packages do such things much better. However, models involving changing contacts, such as a part rolling on another, or gears are always difficult, if not impossible to simulate correctly because the contact forces are computed in a simplified way (i.e do not consider material deformation)
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motion simulation packages (and SW2004) let you insert linear springs in your model/simulation. If you need to compute the deformation of a part subject to its own weight or to external forces, you'll need a finite elements analysis (FEA) add-in such as CosmosWorks, or MSC/VisualNastran or one of the many others.