Floating rigid bodies on Flip fluids.. possible?

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I was playing around with some rigid bodies and threw em in a flip container, I was expecting them to float but they all sink unfortunatley..

Is there any way for them to float?

I found a weird workaround and thats by using a wire spring constraint and keyframe it at the correct time.. but I wonder if there's another way to do so without any constraints..
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Try to increase the feedback value on the flip solver.

Hope that helps.

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Aah thanks!

Was one of the only buttons left I did not use.. ops:
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The feedback value usually has to be pretty high. Impulse force to counteract the mass of the object that you wish to float. Try values between 50-2000 if the sim fits on the default Houdini grid.
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jeff
The feedback value usually has to be pretty high. Impulse force to counteract the mass of the object that you wish to float. Try values between 50-2000 if the sim fits on the default Houdini grid.

This has actually changed for H12, since the FLIP Solver now takes into account fluid density (which defaults to water = 1000) when solving for pressure, which in turn scales the feedback force. The H11 solver was equivalent to treating fluid density as 1.

From the Feedback Scale parameter doc:

A scale factor used in applying feedback forces to other objects. A value of zero prevents any feedback from occurring.

The default RBD object has the same density as water, so to balance with the default fluid density a value of 1 should be used.


Also, the “DensityViscosity” FLIP example shows a combination of variable density, variable viscosity, and a floating RBD object.
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Thats where I got confused.. I was looking for impulse force.. but this has changed in H12..
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So the DensityViscosity example looks to work as expected in 12.1 (the rbd torus of equal density to fliptank fluid returns to the surface, less density floats more) but not in 12.5.469 RHEL64 (torus just falls through the fliptank, does not respond to density)

Wondering if anyone else has noticed this, and perhaps discovered how to get the functionality back? Toggle moved someplace? Docs i missed? Fix in higher 12.5 ver?

thanks.
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ah n/m. examples Feedback scale < 1, default =0. setting to 1 restores normality.
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Hi,
I am trying to control the soft body vellum object (which is pomegranate peels) and I need it to float on the surface of the water sim. The issue is that the everything works except that the fruit sinks to the bottom of the tank.

Do you know how I could approach this?

Thank you

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