private void OnCollisionEnter2D(Collision2D collision)
    {
        if (health == 0)
        {
            Destroy(gameObject);
        }
        else
        {
            health = health - 1;
            gameObject.layer = 3;
            for(int = 0; i < iFrames; i++)
            {
                gameObject.GetComponentInChildren<Renderer>().enabled = false;
                yield return new WaitForSeconds(.5f);
                gameObject.GetComponentInChildren<Renderer>().enabled = true;
                yield return new WaitForSeconds(.5f);
            }
            gameObject.GetComponentInChildren<Renderer>().enabled = true;
            gameObject.layer = 0;


        }
    }