基于网上的方法，但是太灵敏了，修改了一下，如下：

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CellphoneVibrate : MonoBehaviour
{
//记录上一次的重力感应的Y值
private float old_y = 0;
//记录当前的重力感应的Y值
private float new_y;
//当前手机晃动的距离
private float currentDistanceY = 0;
//手机晃动的有效距离
public float distanceY = 0.8f;
//记录上一次的重力感应的x值
private float old_x = 0;
//记录当前的重力感应的x值
private float new_x;
//当前手机晃动的距离
private float currentDistanceX = 0;
//手机晃动的有效距离
public float distanceX = 0.8f;

void Update()
{
    new_y = Input.acceleration.y;
    currentDistanceY = new_y - old_y;
    old_y = new_y;

    new_x = Input.acceleration.x;
    currentDistanceX = new_x - old_x;
    old_x = new_x;

    if (currentDistanceY > distanceY && currentDistanceX > distanceX)
    {
        //实现手机晃动震动效果 
        //Handheld.Vibrate();
        //业务逻辑代码
       
    }
}

}