Violent collisions between RigidDistanceGrid and PointCollisionModel

[wgrosche]

Hello All,

I'm using BeamAdapter with RigidDistanceGridCollisionModel.

Most everything is working as expected but the collision response is very violent (when contact is detected the beam is catapulted out of the offending object). Does anyone know what I can change to get a more realistic response?

I have tried changing the contact stiffness (when using DefaultAnimationLoop with PenalityContactForcefield) and mu (when using FreeMotionAnimationLoop with FrictionContactConstraint) but these just allow interpenetration of the object when brought low enough, which is not what I want. Ideally the beam would collide with the object inelastically so that the beam does not bounce back from the object.

Thank you for your help.

I have attached the scene graph below.

[hugtalbot]

Hey @wgrosche

Would you mind sharing the scene file that you have? It would help to test it because I am not using RigidDistanceGridCollisionModel extensively.

The brutal contact force should come from the "contactStiffness" value that you specify in RigidDistanceGridCollisionModel. Let me explain: using response="PenalityContactForcefield" means that you opt for a penality based response. Using the collision detection output (point of contact with its location and interpenetration distance information), a penality spring force will be applied using the "contactStiffness" you specified. This "contactStiffness" must be tuned to provide the desired contact response. This is a draw back of the penality based response. Else you could opt for a constraint based response.

I hope this helps.
Best.

[hugtalbot]

Could you elaborate on what SDF means "the beam collides often and frequently with the SDF" @wgrosche ?

[wgrosche]

The collision model. @hugtalbot

[hugtalbot]

Could you make us a video recording of it @wgrosche ?
(you can make a video with SOFA pressing the "V" key of your keyboard while a simulation is running)

[wgrosche]

Here is a short recording.

video__r60_0001.mp4

[hugtalbot]

thanks a lot @wgrosche
I think this is due to a bug on our side .. we are investigating it 😉

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@wgrosche
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@wgrosche
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@wgrosche
In accordance with our forum management policy, the last reply is more than 4 months old and is therefore closed. Our objective is to keep the forum up to date and offer the best support experience.

Please feel free to reopen it if the topic is still active by providing us with an update. Please feel free to open a new thread at any time - we'll be happy to help where and when we can.