Emulating Ball Joints

First off, I have a really cool thing going with some simulated trees. The trunk and three leaves have appropriate hinge joints, and you can run into them with your car and knock bananas out of them. :smile: No coding at all. Awesome!

Second off, I'm trying to emulate a ball joint for the base of the tree. I did this by adding a second hinge joint in the appropriate axis. Now I'm thinking this was a very bad idea, as both springs seem to be immovable now, even with ridiculously low spring values.

Will different types of joints be coming in future releases, or is this the extent to what Ageia physics supports?

Cool. Looking forward to your demo.

We will add more joint types in the next release. Let the ragdolls fly.

What types of joints are you expecting to add? From what I understand, Unity used to use ODE for physics, no? I've used ODE, and I can't imagine Novodex is TOO different in terms of what's available... so can we expect things like ball joints (mentioned above), fixed, universal, etc? Could we be so lucky as to get something like ODE's Hinge2 for 'shocks' on vehicles :smile: ?

I've had some trouble trying to simulate some of these other joint types with a Hinge... I assumed "fixed" would be suited by something with a high spring and 0 angle (though of course MUCH more computationall intensive than a fixed) I see some of the docs mention being able to use the Hinge for other things... how exactly are you accomplishing that? Or should I just wait for the new joints in an upcoming release?

Take a look at arkuu's demo:
http://www.tc.umn.edu/~czec0035/unity/unityrobot/

It uses shock absorbers made with the hinge joint.
You create one rigidbody for the absorbers. The hinge axis is along the forward direction of the car.

Then that rigid body has another hinge joint and connects to a wheel rigidbody with spheres as colliders. The hinge axis of it is to the right of the cars moving direction.

Then you have to play around with the spring values etc and give the right anistropic friction values to the wheels. You can use the PhysicMaterial's script interface for that.
An example which uses it is the raycast car in the physics demo folder.

We will be adding more joints. Ball joints will definately be supported.

And 12 years later...

5 Likes

15 years and still counting...

1 Like

16 going on 17....

1 Like

19 years… COME ON UNITY

1 Like