Hello everyone,
I’m trying to implement a mechanic where my character is tied to a wall with a chain or rope, limiting their movement to the object’s length.
My main goal is a realistic physical simulation: the chain should sag when the character is close, and become taut and prevent movement when they reach the radius limit.
I initially tried creating the chain using a series of connected Rigidbody components with Hinge Joints. However, I’m running into problems: the joints frequently break or the entire physical simulation becomes unstable when the character moves quickly or pulls on the chain too hard.
What is the most reliable way to create a physically constrained and visually realistic rope/chain in Unity? Should I be using a different joint type, a specific asset, or perhaps a completely different, non-joint-based approach for the constraint?
Any advice on solving the Hinge Joint instability would be highly appreciated!
Thanks!
You should use a Rope physics asset. Regular Rigidbody physics is terrifyingly difficult to make behave like a chain or rope as a sequence of joints.
If the joints break, you probably set the break limit. It should have a “never break” value, either negative, zero, or infinity (check manual).
If the chain “explodes” ie and flies off in one or more directions, it’s a matter of limiting constraint forces on each joint. You also need to disable collision between jointed bodies ie no chain element must be able to collider with another as this can eventually accumulate tremendous “constraint-resolving” forces.
Hinge joints are probably not the ideal joint type. I’d try fixed joints as they have no angular limits - those angle limits increase chances of explosive behaviour. Fixed joints, contrary to their name, do allow for stretching. Alternatively a configurable joint can be made to work.
oh thank you so much. It was “infinity” yes.. and what you said makes a lot of sense. I will try it. If I succeed, I will share it here.