AddRelativeTorque doesn't work

Unity Engine
1

I have this script:

ball.transform.LookAt(ball.transform.position + ballvelocity);
ball.GetComponent.().AddRelativeTorque(Vector3(5000,0,0));

why the ball rotates on all axis?

2

I wouldn’t expect any of that to work properly:

  • rigidbody has a configurable angular velocity limitation
  • you’re assigning a transform rotation and fighting the physics engine
  • goodness knows what else you’re doing around that little snippet

Perhaps you could consider decoupling mesh transform from physics?

3

function Start () {
ball.GetComponent.().maxAngularVelocity = 200;
ball.transform.LookAt(ball.transform.position + ballvelocity);
ball.GetComponent.().AddRelativeTorque(Vector3(5000,0,0));
}

I want that ball rotates on the direction of its velocity.

4

But this is in Start() so it is only executed once. Please use Code Tags.

This chart can help visualise issues:

5

I noticed that if ball rotation = (0,0,0) the relativetorque works correctly and rotates the ball on x axis. But when i change the ball rotation the relativetorque rotates the ball on all axis.

6

If i put a “Constant Force” element on the ball, the relativetorque works well even if the ball rotation is not = (0,0,0). So, how can i have the same result with the script? Thanks

7

Why it rotates the ball in all axis and not only on x axis? I should have (x,10,0) but it isn’t so. It’s so strange…

8

Ok, this is the key:

GetComponent<Rigidbody>().rotation = Quaternion.Euler (0,10,0);

I have transfom.rotation in my script, that’s why it doesn’t work. I have to rotate the rigidbody and not the transform before adding the force.

9

Rotations use Quaternions! You are trying o use Vector3 to do rotation. Follow the example that Eron82 shows.