Defining where an object rests

Hi!

Does anyone know how i would get a dropped/tumbled object to rest in a pre-defined position/location?

it has to look natural but I can be flexible with the starting position.

Cheers :slight_smile:

It really depends on what you specifically want to do. Does it just fall on a plane or does it interact with anything else in the scene. For just falling on a plane see below

Use the rigid body sim to drop your object onto a plane
Bake your rigid body simulation.
Convert this simulation to keyframes. Select your object, press Spacebar and search for bake. Select '‘Bake to Keyframes’. Select the frame range and press Ok to bake.
Now change these keyframes to Delta keyframes. Select your object, press the Spacebar and search for delta. Select ‘Animated Transforms to Deltas’
Now go to the end of the animation and moved the object to where you want it to finally rest

Thank you very much for replying Richard! That makes perfect sense!

Also though, do you think it would be possible to have, for example, three lines of text as three separate objects colliding with each other and even other objects then landing perfectly aligned to form a sentence. I.e. is there away to define the end positions and have Blender somehow calculate where they start positions should be to achieve that result?

Cheers :slight_smile:

Wow! And I thought the guy wanting to build a quadricopter with rigid bodies and wind was a mad scientist… :smiley: You beat him! :wink:

First, there’s no Inverse Rigid Body feature in Blender, so… The answer to your question is no. However…

I got a really crazy idea. Start from the end and inverse the gravity. You set your text as you want it to land, give a very little impulse to the objects to send them on a trajectory toward a collision. In the end, you should obtain the inverted sequence of your objects colliding and falling in position.

After that, it’s just a matter of reversing the order of the frames to get the effect you want.

Of course, as I said, it’s a crazy idea… and untested. YMMV. :wink:

You can do the trial and error approach using the Motion Paths option as a guide to see the track of your object so you can adjust the initial speed and direction to give the approx final position. When you have real keyframes you can manually correct any final adjustments


This a pretty tricky problem.
There are papers on this but I dobut it would work for anything more than very simple scenes.
Simulations are hard to predict, especially when several dynamic objects are involved, the more there are the more difficult it is.
Even small changes to the initial setup can lead to a drastically different end result.

So your best bet is Richard’s suggestion.

Thank you everyone for your suggestions! I’m so sorry I took so long to reply life got in the way and this project has been put on hold for a while. I’m looking forward to experimenting with these ideas once I return to the project though!

Thanks for your help!