I have a constraint car with suspension that uses 2 CylindricalConstraints and a SpringConstraint and whatever I try to do to make it work it just keeps on flinging itself or straight up disappearing before I even get to see it fling. Here is the car:
brokensuspension.rbxm (9.5 KB)
I have been losing my mind at this for multiple hours, so any help is greatly appreciated.
Your motors are set to insane values, the physics engine can not handle these.
Lowering them down stops them from disappearing
Also the springs are set to insane values too, when roblox studio starts saying “INF” you need to lower them down.
The motor worked fine on another car I had that had almost the exact same setup when it comes to weight/size, and the same constraints were used
Also I am pretty sure the inf is default when it comes to spring MaxForce
Default doesn’t mean you always need it set to that.
I’ve never used a MaxAcceleration for my Motors higher than about 1000, and that’s only for small items that I need up to speed instantly.
I’ve set my MaxTorque to about a million. After that the vehicle wheels start to move by themselves. I generally set them back to a really low value to keep this from happening when a vehicle is sitting without a driver.
I can’t open your file right now at this computer.
Do you have Parts that are colliding with each other and flinging it?
Do you have some of your Attachment Orientations set up misaligned?
Nope, collision groups and attachment orientations are all good
Here is a video of what happens
So just try reducing all your numbers.
Your car and wheels have very little mass.
Huge forces WILL fling it.
Also put limits on the lengths of your springs.
What do you think is the optimal weight for the car/wheels?
When each physics based Constraint car is built you have to tune the suspension and HingeConstraints to that car so I can’t say for sure.
I start with fairly heavy wheels (Density 1-2) and a fairly light chassis.
The forces on the wheel Hingess depend on the size of the wheels and the mass of the car.
Also don’t fine tune the chassis and wheels too much if you plan on adding other stuff to the car, the handling will probably be affected so you would have wasted your time and effort. Get it close, build your final car setup, then do your final tuning.
I tried different weights/properties and the same problem is still occuring. It’s either the springs don’t have any power at all or they have so much power that the entire car flings itself, with no inbetween.
Try setting all your spring forces to about 500
Set your Hingeconstraint:
MotorMaxTorque 500
MotorMaxAngularAcceleration 10
If it doesn’t make a difference I’ll try having a look at your model in about 12 hours.
It only took me a few minutes to figure this out.
You still had your Spring MaxForce at inf.
I set all 4 springs to MaxForce 10000 and Stiffness 8000, hit test and the body part bounced gently.
The biggest issue is that you had all the Parts set to CustomPhysicalProperties, and the Holders were set to Density .01. That’ll mess stuff up when dealing with physics. All your suspension Parts should have about the same Density. In Roblox you have to match them up.
You also had many of your limits not set for your suspension angles and lengths. This is important to keep springs and suspension from getting bounced outside it’s limits.
Here’s your car ‘fixed’, and a copy of a simple car I made. You’ll see I used a Motor instead of Cylindrical Constraints to actuate the steering. This makes it easy to set up Ackerman steering so that the inside wheel turns more than the outside because it turns a smaller diameter circle than the outside wheel.
brokensuspension.rbxm (16.7 KB)