Strange behavior of rigidbody

Unity Engine
1

Hi

I’m trying to make a gun that fires missles according to gun’s direction (nothing new or original), but I met strange problem. I create missle as below:

GameObject m = (GameObject)Instantiate(missle, missleStartPosition.position, transform.rotation);

And now:

  1. When missle doesn’t have rigidbody component and I use on it
 transform.Translate(Vector3.forward * speed);

everything works fine. But when I attach rigidbody to it and do either

GameObject m = (GameObject)Instantiate(missle, missleStartPosition.position, transform.rotation);
m.rigidbody.velocity = m.transform.forward * shootingPower;

or

GameObject m = (GameObject)Instantiate(missle, missleStartPosition.position, transform.rotation);
m.rigidbody.addForce(m.transform.forward * shootingPower);

It almost works only when m.transform.forward.x > 0.2 (then direction is only a bit shifted to the right). If 0 < x < 0.2 then missle flies a bit right (like x = 0.2) and when x < 0 then it flies like x = 0.
Rotation and direction seem to be ok. Checked with:

  • just translate without rigidbody
  • Debug.DrawRay
  • it almost works for x > 0.2

What do I do wrong?

2

I did more tests and conclusion is: only missle ‘cube’ moves like intended. ‘Sphere’ behaves very strange (like described above) and trajectory of ‘capsule’ is similar to ‘cube’ but has small (but visible) deviation.

What is the cause of such behaviour?

3

It seems to be a bug. After restart of Unity everything works as intended.