Vehicle motors accelerate and decelerate slowly along the X axis

I’ve been reworking my trucks and cars to be PSG physics compatible. I’ve run into an odd physics glitch with both my cars and trucks where the motor acceleration/deceleration varies depending on the axis I am driving along. Along the Z axis, acceleration behaves normally but as I turn towards the X axis, the acceleration slows down. My cars lose handling and skid out of control very easily along the X axis. When I suspend the vehicle in the air (anchor the base) along the X axis, the motors accelerate normally when not in contact with the ground.

Here is a demo of the glitch. Just place the local script into PlayerScripts https://www.roblox.com/library/1158590874/Truck-Glitch-Demo

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Make your wheels heavier: change their density from 0.7 to 5. The issue is that you have a heavy vehicle body sitting on light wheels causing stress and unpredictable behavior in the engine. Let me know if this helps.

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Thanks! That helped significantly though the truck still accelerates roughly twice as fast on Z axis.

Hmmm that’s weird, I can’t seem to reproduce that. Could you send me your place?

I’ve noticed for a while since PGS that when using a properly designed constraint system on Aircraft or Land Vehicle that when turning there seems to be some drag force that quickly slows the vehicle down especially when turing on to the x axis and no matter what force you use you can’t pick up speed in that turn till its an absurd amount which is unrealistic. Video of issue: https://www.youtube.com/watch?v=350zvA5Jefs To avoid this you have to be traveling pretty fast into the turn which isnt nearly as realistic for vehicles like aircraft and tug tractors as these operate into turns usually at low speeds. The vehicles definately have enough torque but there seems to be an overpowered force that negates this in turns. Ive messed with friction, elasticity, friction weight, changed the weight of vehicles and planes, It definately isnt an issue with any of those. Dued1 mentioned a very similar issue back in 2017 without solution, I assume this is the issue he hadn’t managed to get a solution for

Can you explain exactly what is going on that could potentially be causing this issue (or perhaps describe it more clearly because i don’t really understand)? Have you also verified that it does not have to do with the chassis itself? I have made several vehicle chassis before and I don’t ever remember turning behaving any differently depending on the axis I steer on. You could try it in this demo game I made where the car doesn’t have much torque and I cannot seem to reproduce it. It moves through the use of modern physics constraints and engine simulation.

The issue has also been mentioned which is direct slow down going into turns even with high torque(engine power) towards X axis. If the issue is Chassis base(I doubt so as ive tested numerous times) then the next issue would be is their some documentation on know chassis rights and wrongs of which may lead to slowdowns in turns even with power. PGS isn’t fully covered yet especially if you want to use proper weighting for vehicles id like to know if it isnt an engine bug then what exactly causes this slowdown so I can avoid it, would also be a great start to a PGS troubleshooting guide.