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Boxes and elevator problem

Hello!
I’ve created an elevator that moves with acceleration. Player and AI move just fine while staying on it, no jitter or anything. But boxes don’t. I have some default boxes (the ones that go with default FPS project), if elevator moves upwards, boxes just freeze in their positions, while elevator just moves through them, and then they fall down. However, if I touch or move the boxes right before elevator’s departure, they will stay on the elevator’s platform and move with it, so I think it is related to sleep/awake physics state. Anyway, I couldn’t find a way to fix it… Also, I use UE5.

If sleeping is the problem, then you could make a trigger box component in the elevator, and wake up any actors inside of it.

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Thanks, that worked! However, boxes still may jitter or even jump during elevator’s movement. How can this be fixed?

If you don’t need to simulate the boxes while they are inside the elevator, then you can just disable physics, and move the boxes manually with the elevator. If you do need physics, then you might require CCD, or physics substepping. Unfortunately, you will probably need a hacky solution for this, as Unreal Engine’s physics can be…problematic. :slightly_smiling_face:

Or plain sh it. Call it what it is.

@Necronomicron8
Have you tried adjusting the weight of the boxes to something that would make the elevator not work?
Do they still move?
(If they do, that’s just proof of what we both told you already).

Technically speaking though. If they are asleep they should move with the platform like any other box without simulate physics enabled would.
Ergo.
Change the trigger to turn off simulation when the elevator is moving…

Boxes have already had CCD enabled, enabling it for the elevator didn’t change anything, as well as disabling it for boxes. Changing boxes’ mass didn’t change anything either. Boxes jitter and jump with or without trigger.

Which is why disabling physics while the elevator works will be just about the only solution short of increasing the inertia past where anything can move them…