private void OnTriggerEnter(Collider other)
 {
     if (!other.CompareTag("Gun"))
     {
         return;
     }
     kinematicCalc           = null;
     transform.parent        = other.transform;
     transform.localPosition = initPosition;
 }
 public void Launch(Vector3 acceleration, Vector3 speed)
 {
     kinematicCalc = new KinematicCalc(transform.position,
                                       speed, acceleration
                                       );
 }