New constraints are live!

Yes use front wheel motors! Much better stability. Even against a 4 WD.

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You want to change the friction on the ground and on your tires. Otherwise you’ll get a boring plastic on plastic. Use “CustomPhysicalProperties” and input a friction value. For tires you wanna use the highest possible 2, and a higher FrictionWeight as well (around 1.5).

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Yeah, I tried that right after posting that. It turned out really great, but I don’t remember if I published it or not. It makes the car track really nicely.

EDIT: I published it, drives great!

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Are there plans for torsion spring constraints?

Similar to regular springs, where F = -kx, but for torque instead of linear force: 𝜏 = -kθ.

It looks like you can almost do this with hinge constraints using restitution, but I can’t quite seem to be able to get the range I’m hoping for out of that. A saloon door is one use case.

The only other way I could think of approximating this is with a hinge and a spring on a lever, but this is only effective for small angle changes.

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Yes we will implement torsion springs. But you can’t use a hinge with restitution for this. Restitution is like in collisions, how much your object responds when it hits the limit, specifically the hinge limits

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You can use a motor or a servo, and write a script controller

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By the way, my buggy is now unlocked, so learn and create:
https://www.roblox.com/games/460776678/Dune-Buggy

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Ah, that makes sense. Thanks for the clarification.

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To the people who worked on the constraints,

you dun good.

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If using PGS, is there a technical difference between using Rotate objects or surface hinges vs using hinge constraints? That is, in the case of a free spinning hinge. Using constraints is proper and all, but man it’s just so easy when you just need a free spinning wheel or whatever to just slap it on with a surface hinge.

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Yes, there is a difference. Hinges will try extremely hard to be in the correct position. If something gets in the way, they respond with unreasonable force. All the warnings about interpenetration and all that.

That’s why things bug out in Lumber Tycoon 2. If you’re in a trailer train going down the mountain with a large log load, and a log stays back for a split second, it forces the trailer wheel to interpenetrate throwing everything into disarray.

Joints/Constraints on the other hand:

They’re pretty cool about not being in the right place, and will spring back. It creates a smoother experience and that’s why I had so little trouble assembling the 70-strong trailer train. (In fact, the only issue I had with the trailer train was one of the wheels getting out of its wheel well. I managed to pop it back into place by dragging the trailer around).

EDIT: to further clarify, I did an experiment with the joints, and here’s what I found: a little phantom energy is applied to the system upon overconstraint, compared to a lot of phantom energy when a hinge is overconstrained.

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Hah, nice! I thought that I was the only one who did this. I only have 25 small trailers though, but I hope to get more. How well are you able to move around the map? I can’t go up hills if too many trailers are pulled up the hill at once, and I almost reached the point where walking was faster than driving.

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My plot was the closest to the mountain, so I was descending the hill when I began. Driving it was much slower than walking: it took half an hour to make a U-turn around the rocks next to Wood R Us, and the footage in the video of me driving is sped up 4x. The best part is, not only did I drive with 70 trailers in tow, I also carried a load in it: at the very end of the video I discover that someone placed a log in the second-to-last trailer.

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Surface hinges and free spinning ConstraintHinge under PGS internally use the same implementation. So yes you can use these surface hinges and expect same results

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You sure can do a lot with the new constraints.

Unfortunately, it is has a high tendency to spaz out when it touches the plane, and parts of it are CanCollide false to prevent further spazzing. Collision filters would help but they aren’t out yet.

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What am I doing wrong? :frowning: I thought the new Hinges were suppose to be stiff and not allow rotation on other axises.

Open view of Joints.
https://i.gyazo.com/387cfc1b912ac3e40b28963f209229c3

If I up the mass of the tires, they just fall off their axis.

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You might wanna increase the mass (density) of the knuckle - the tiny part that you attach the wheel to.

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By the way: Constraint UI is live! Still in testing for few days, so it may be turned off. We’ll make an announcement next week.

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Ran into a bug with the RopeConstaint at Spiderman Simulator.


I think that the constraints go off when you are interacting with something you have physics ownership and something you don’t. The constraints are done locally with FilteringEnabled.

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I read the blog on the new visual improvements to creating the constraints in studio (as opposed to with scripts only)

YESSS, THANK YOU! :smiley:

This will also dramatically increase the amount people will toy with this stuff. With Lua coding you had to be more serious/ determined with the approach, while now it’s a lot more accessible. We’ll be seeing a lot more cool stuff.

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