deformable solids attached to rigid bodies

[soldierofhell]

Hi, I wonder if we can simulate deformable solids attached to rigid bodies (attraction force of boundary particles toward rigid body?), something similar to this example from Corotated SPH for deformable solids

Regards,

[janbender]

Hi,

you can fix particles. This you can define by defining a bounding box in the scene file (just recognized that these fields are missing in the current documentation):

• fixedBoxMin (vec3): Minimum point of box of which contains the fixed particles.
• fixedBoxMax (vec3): Maximum point of box of which contains the fixed particles.

All particles which are initially in this box are then fixed and cannot move.

Hope that helps!

[soldierofhell]

Thank you for your answer, but actually I'd like to achieve a bit more, I'd like to attach deformable object to rigid body, so I could actuate rigid body and thus steer the deformable.. in the water. Even if this is currently not possible, could you guide me what has to be potentially added? Regards,

[janbender]

This is not supported at the moment. You could achieve this by defining a constraint:
C = a - b = 0,
where a is a connector point in the rigid body and b is the position of a particle in the deformable solid. Typically, a = R * a_local + t, where R and t are rotation and translation of the rigid body, and a_local defines the position of the connector point in local coordinates.

With this constraint you could either attach the solid by penalty forces or use a position-based approach (PBD). In both cases you could compute additional forces which you consider in the time integration.