Collision priority and actors going through other objects

Hello everyone!

I’m trying to build a simple object using intensive physics.

It’s a static tube mesh with a key locked in it. the goal is to bring the key to the end of the tube so it can fall on the floor. Then only the player can handle it and use it to unlock something.

The main problem is that when I hit the key with the vive controller, it fall easily through the tube, even on the straight part!

here are the properties of the Key_BP

And here are the properties of the tube:

I tried to play with the settings, damping, mass and gravity, but i cant found any working configuration.

Do you guys went through this problem?

Thank you!

How do the collision meshes look like on the tube and on the key? Are they using complex collisions or simple collisions? In particular for the key, being hollow, you may have to setup a custom collision mesh for it to hold properly on the tube.

I tried multiple approaches for the collision mesh. i tried first the “using complex collision as simple” , i tried making it by hand using multiple boxes and capsules overlapping one another, and then i tried using the “auto convex collision” with the precision settings pushed to the maximum.

The key holds on to the tube but whenever i just push it downard (without grabbing) it goes through the tube.

Thank you !

You hand being tracked and unsimulated doesn’t have any give to it and is effectively infinite force in the game world. Either the hand has to pass through the key or the key has to move out of the way of the hand in the physics simulation.

You can try applying force to the key on overlap instead, basically faking the push instead of directly pushing it around. Or have the key follow the hand manually, or tie a constraint to the two on impact, or have a collision object on the hand that is constrained so that it has some give to it, or a hundred other work around methods.

Regardless of tweaking settings, pushing an effective infinite force / mass object into a physics simulating object isn’t going to be stable, even with continuous collision detection on and high physics precision you will run into issues when people intentionally break it like pushing down into a blocking mesh.

Thank you Mordental, so if i understand well, i need deactivate the key collision with the player pawn. Then i need to make a blueprint for the key that detects the direction from where the player is pushing the key, and apply a force to it?

That is one method yes