【Unity】キャラクターを自動で左右に移動させるスクリプト

// 移動速度
public float speed = 2.0f;

// Rigidbody
private Rigidbody2D rb;

// Use this for initialization
void Start () {

    rb = GetComponent<Rigidbody2D>();
       
}
	
// Update is called once per frame
void Update () {

    // 移動
    move();

}

private void move()
{
    rb.velocity = new Vector2(speed, rb.velocity.y);
}

private void OnCollisionEnter2D(Collision2D collision)
{

    if ("Side" == collision.gameObject.tag)
    {
        speed = speed * -1;

    }
}