I’m making a car racing game and I’m working on a car with suspension. I’m aware that having many constraints and updating them constantly with Run Service could get pretty laggy for mobile players/non-gaming laptop users, so I’m only using constraints on the client side. (The server will just update the car position with maths)
I’ve taken some inspo for the constraints of the car from Roblox’s racing template, however my car seems to be bugged. Although there’s a bounce, the wheels are off(they spawn tilted), and generally the entire model is acting up. I even double-checked all the properties, attachments and constraints, they’re exactly like Roblox’s car. Any idea why it might be acting this way?
I’m not very experienced with constraints to I’m a bit lost. Here’s what the car looks like bellow(sorry for the low quality btw):
You have to get the SteeringRack RodConstraint right and the wheels need to be true to start with.
Don’t give up on deconstructing that car.. Once you get it down to just a frame, it can be any car you wish.
Go into your model tab and in the Constraints section click the Show Constraints tool. It’ll show you exactly how your Constraints are set up.
Click on the rear wheel HingeConstraint, I’ll bet it shows you 90° misalignment of the wheel. Either that or you have a weld between parts of the wheel that’s set to 90° from where it should be.
As @2112Jay said, look at the lengths of the steering rod links since the geometry of your steering and suspension is different than the Roblox car.
Also experiment with the properties of the SpringConstraints. You’ll have to tune them to the weight of the vehicle which is likely different than the Roblox car.
Actually, just clicking on the RodConstraint highlights them.. If they are red, they are set incorrectly for length. @Phoebe, if you look at my picture, you can see the orb-shaped wheels. All the frames to the right of them and on the car are using those orb wheels. The ones you see are fakes. My frame works perfect.. everything else is welded to it.
I know this may seem odd, but it works well. Those wheels align no matter what.. they are orbs. Welding a different looking tire to them is easy. This was a major issue until I tried this.
I’ve taken a look inside the rod as @2112Jay said, they’re red and there’s a warning popping up: ‘Distance between attachments is not equal to the lenght of the road. The constraint will sharply move the two parts until the distance between attachments becomes equal to the rod’s lenght. This can cause instabilities in complex mechanisms.’ I fixed it but it didn’t really make a difference
I’ve already tried this since Roblox’s car also uses sphere-shaped wheels to move (it’s also the most convenient way to go since you can just switch up the wheel models)
This is more why I did it this way than anything. You can see your rods are off. Adjust the RodConstraint number. Find the lowest number that isn’t red and then find the highest number that isn’t red. Pick the number right in-between that.
Yes, but you’re setting the rod length in Edit mode, then when you test the suspension is pushing up. Depending on where your alignment for steering is that will affect the position your wheels end up.
Try fixing the suspension SpringConstraint settings first to get the car sitting properly height wise. THEN adjust your Rod length. If the steering changes too much while the suspension pushes up and down while driving you may want to look at where your ‘steering box’ is located. Drop it down to the height your steering ‘arms’ are at so it’ll be more of a straight run.
I’ve done a ton of posts about steering and suspension on the forums, many with sample cars you can look at for things exactly like this. Have a search for Suspension and use my name in the ‘posted by’ search tool. You’ll probably find them pretty easily.
I looked into it, the issue was both in the spring and rod constraints, and the wheels on the back weren’t working bc I set them up like the front when they’re supposed to work a bit differently.
