Invert the rotation of a moving object

Questions & Answers
1

I need to rotate an object instantly by 180 degrees at the press of a button. The object is moving, I can rotate it on its Z axis using the joypad. Then, if I press a key I need my object to immediately invert its direction (ie: if it’s moving left, it flips and starts moving right).

I tried using Quaternion.Inverse, but it’s not working :confused:

Can you explain to me why not and point me to the right way to do it? (Sorry I’m kinda a newbie with Quaternions)

var craftSpeed:Vector3 = Vector3 (20,0,0);
var eulerAngleVelocity:Vector3=Vector3 (0,0,200);
var controlAxis:String ="HorizontalP1";

function Start () {
	rigidbody.velocity =  craftSpeed;
}

function FixedUpdate () {
	// this aligns the velocity with the right vector, it makes the plane move towards its nose
	rigidbody.velocity = Vector3.zero;
	rigidbody.velocity = transform.right * craftSpeed.magnitude;

	//this one just rotates my plane on input
	var deltaRotation : Quaternion = Quaternion.Euler(eulerAngleVelocity * Time.deltaTime* Input.GetAxis(controlAxis));
    rigidbody.MoveRotation(rigidbody.rotation * deltaRotation);

    //and this one SHOULD make the plane invert direction on input
    if (Input.GetKeyDown ("q"))
    {
    	rigidbody.MoveRotation(Quaternion.Inverse(rigidbody.rotation));
    }
}
2

transform.rotation = Quaternion.Inverse(target.rotation);

3

You can also do this:

transform.forward = transform.forward * -1;