如何使一个对象掉落时，离开触发区

我试图使一个对象掉落时退出"触发"区域在我的游戏。当我进入触发区，物体开始漂浮。但是当我离开这个区域时物体不会掉回地面，它只是停在半空中当我再次进入触发区域时它继续漂浮?

这是我的脚本浮动:

using UnityEngine;
using System.Collections;
public class Floatinga : MonoBehaviour {
public float horizontalSpeed;
public float verticalSpeed;
public float amplitude;
 private Vector3 tempPosition;
 void Start () 
 {
 tempPosition = transform.position;
}
 void FixedUpdate () 
 {
 tempPosition.x += horizontalSpeed;
 tempPosition.y += verticalSpeed;
 transform.position = tempPosition;
 }
}

然后当我进入或退出时:

using UnityEngine;
using System.Collections;
public class Floating : MonoBehaviour {
public GameObject otherObject;
// Use this for initialization
void Start () {
    otherObject.GetComponent<Floatinga>().enabled = false;
}
void OnTriggerEnter()
{
    otherObject.GetComponent<Floatinga>().enabled = true;
}
// Update is called once per frame
void OnTriggerExit ()
{
    otherObject.GetComponent<Floatinga>().enabled = false;
}
}

所以我不确定我做错了什么?有人能帮忙吗?由于