I have a comp where there are walls of text objects. All of the text objects are rigid bodies. The word "TRUTH" has gravity applied which I applied by setting the rigidsolver start time to frame 150. After the collision occurs, I keyframed the magnitude of another instance of a gravity field on the rest of the text objects so they did not fly off into space. When I watch the simulation in Maya, the text objects fall the same way every time. When I render it out, the fall and collisions are different every time. Since the initial states should be the same every time, unlike nature, the system should not be chaotic and behave the same way every time. Is there a parameter that is applying random behavior that can be controlled? I want the camera to fly in tight on one of the words after it collapsed, but because the system is behaving chaotically upon rendering, there doesnt seem to be a way to tell where it's going to land.
I am also getting error messages in Maya that there are rigid body interpenetrations, but there are no interpenetrations before the collapse starts and the error messages don't start until I play through the collapse in Maya.
With dynamic systems like particles or physics, the simulation is always ran unless you bake it. Even if you are getting -mostly- consistent results there is usually some margin of play in the simulation. And at render time you don't even get to see how its simulating.
To bake the animation for rigid bodies - go to Edit -> Keys -> Bake Simulation. This should run the simulation once and create keyframes for the rigid body.
For other kinds of dynamics like particles, there are ways to create a disk cache for the simulation.