HingeJoint.spring

Description

The spring attempts to reach a target angle by adding spring and damping forces.

The spring.spring force attempts to reach the target angle. A larger value makes the spring reach the target position faster.

The spring.damper force dampens the angular velocity. A larger value makes the spring reach the goal slower.

The spring reaches for the spring.targetPosition angle in degrees relative to the rest angle. The rest angle between the bodies is always zero at the beginning of the simulation.

function Start() {
	var hinge = GetComponent.<HingeJoint>();
	
	// Make the spring reach shoot for a 70 degree angle.
	// This could be used to fire off a catapult.
	
	var spring = hinge.spring;
	spring.spring = 10;
	spring.damper = 3;
	spring.targetPosition = 70;
	hinge.spring = spring;
}

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    void Start() {
        HingeJoint hinge = GetComponent<HingeJoint>();
        JointSpring spring = hinge.spring;
        spring.spring = 10;
        spring.damper = 3;
        spring.targetPosition = 70;
        hinge.spring = spring;
    }
}

Modifying the spring automatically enables it.