Jiggling Camera

Hey i'm trying to create a spaceflight game and have found a camera script that's perfect except it 'jiggles' when following an object.

Script originally from: http://answers.unity3d.com/questions/20172/space-game-camera.html

 var target : Transform;
 var distance = 3.0;
 var height = 3.0;
 var damping = 5.0;
 var smoothRotation = true;
 var rotationDamping = 10.0;
 
 function Update () {
     var wantedPosition = target.TransformPoint(0, height, -distance);
     transform.position = Vector3.Lerp (transform.position, wantedPosition, Time.deltaTime * damping);
 
      if (smoothRotation) {
          var wantedRotation = Quaternion.LookRotation(target.position - transform.position, target.up);
          transform.rotation = Quaternion.Slerp (transform.rotation, wantedRotation, Time.deltaTime * rotationDamping);
      }
      else transform.LookAt (target, target.up);
 
 
 }
 

 

The link suggested above says someone encountered the same issue and fixed it by adding 'time.deltaTime' but my object is controlled by rigidbody forces so I don't know how to do that.

Movement Script:

 function FixedUpdate () {    
     var roll = Input.GetAxis("Horizontal");
     rb.AddTorque(transform.forward * torque * -roll);
     var pitch = Input.GetAxis("Vertical");
     rb.AddTorque(transform.right * torque * pitch);
     rb.AddForce(transform.forward * thrust * 2 * boost );
 }

How would I stop the 'Jiggling' or add time.deltatime to my script?