Roblox constraints issue

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#1

I’ve noticed recently that my vehicles have begun to suddenly suffer from a unique physics issue, and a game-breaking one at that.

I also am unable to post inside of bug reports so this is the next best option.

When regenerating vehicles with wheels, for a few moments they regenerate normally, then suddenly start breaking, errors include flashing in and out of existence, causing physics errors when the player interacts with them, launching the vehicle in the air, shifting the wheels around (the most common), and sometimes outright disappearing.

The only fix I’ve seen is quite literally regenerating the entire marauder series of vehicles several times over until they are all working properly, I do not know what causes this error but it’s only experienced in-game, I cannot replicate it inside of studio at all. It seems to originate from some form of a physics pause, the game does not have streaming enabled active at all so something is causing the physics to bug out.

While this one may be a coincidence, I’ve noticed that when the error occurs my CPU and GPU temps rapidly climb, higher than any other game I’ve played, such as Halo and ArmA 3 with the latter being incredibly demanding.

Another thing I’ve noticed is that sometimes when this bug occurs, the vehicle floats in the air for a few moments, something which doesn’t happen with other vehicles, before nearly tearing itself apart, it looks to be like a physics pause that occurs regardless of what happens.

The wheels utilize a spring constraint for suspension, a hinge constraint for rotation (they freely rotate along the ground), and a prismatic constraint used as a limiter.

Here is the game in question: Game

Here is a video of the error

1 Like
#2

Are the Parts interacting with any of the chassis Parts, causing them to be pushed out of the way? There is a Studio setting that allows you to see Collisions between Parts when testing, showing those collisions as red spheres.
I’ve also had minor issues with suspension going beyond where it should. Have you set the limits for the Prismatic and Spring constraints so they don’t exceed those limits?

#3

The parts don’t interact with the chassis, and any potential parts they could interact with are nowhere near the wheels themselves, most of the model doesn’t have any collisions. The springs and prismatic constraints do have limits set, however, they don’t seem to do anything at all.

And this issue I only experience in-game, I cannot replicate it inside of studio at all.

And even if physics was the issue, how would regenerating the Marauder IFV series miraculously fix the other vehicles?

Also, even setting every part minus the wheels collisions to false still didn’t fix it at all.

#4

Prismatics seem to have had issues with snapping past their limits in some of my games, particularly in my construction site game.
Do you have the Springs limiting the travel as well so the wheels shouldn’t go above the chassis Parts?

#5

Yes, that’s how the constraints and prismatic constraints are set up.

In fact, oftentimes the wheels quite literally extend past their limits

#6

I think Im having this issue as well:
robloxapp-20210726-1325589.wmv (1.6 MB)

I set the constraint so that the limits can be easily seen, the moving part involved is cancollide false so it should not be bumping into anything.

rather than freely sliding up or down it instead begins to bounce out of control.

#7

The Density of the attached Parts can affect the Constraints as well.
If you have Parts set to Massless they seem to strain the Constraints.

#8

Happens in my game too, I use Customphysical property and set the density to 0.001-0.01 and dont use Massless. And keep damping above like 300