我怎样才能停止太空中的物体？

问：

Unity，如何停止我的对象？

我是Unity的新手，但我已经在制作一个小游戏了。问题的本质如下： 我有一枚火箭飞向目标，在某些空间间隔内，我需要停止火箭，以便以文本形式显示其他参数 如何以及在何处将代码插入到我的脚本中，或者最好强加一个新代码 更详细地解释，我将不胜感激！

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

public class missileparticles : MonoBehaviour
{
    private Transform target;

    public enum Missile_state
    {
        idle, 
        start, 
        fly, 
        end 
    }
    public Missile_state missile_state_t;

    float timer = 0;

    public float speed_move;
    public float speed_rotate;

    Vector3 start_pos;

    public Transform GetTarget()
    {
        return target;
    }

    public void SetTarget(Transform value)
    {
        target = value;
    }

    
    void Start()
    {
        SetTarget(GameObject.FindGameObjectWithTag("Target").transform);

        start_pos = gameObject.transform.position;
    }

    
    void Update()
    {
        switch (missile_state_t)
        {
            case Missile_state.idle:
                if (timer <= 5) { timer += Time.deltaTime; }
                if (timer > 5)
                {
                    missile_state_t = Missile_state.start;
                }

                break;
            case Missile_state.start:
                float start_dist = Vector3.Distance(gameObject.transform.position, start_pos);
                gameObject.transform.Translate(Vector3.back * speed_move * Time.deltaTime);
                if (start_dist >= 20)
                {
                    missile_state_t = Missile_state.fly;
                }
                break;
            case Missile_state.fly:
                gameObject.transform.Translate(Vector3.up * speed_move * Time.deltaTime);

                Vector3 target_vector = GetTarget().transform.position - gameObject.transform.position;

                gameObject.transform.up = Vector3.Slerp(gameObject.transform.up, target_vector, speed_rotate * Time.deltaTime);

                if (target_vector.magnitude < 1)
                {
                    missile_state_t = Missile_state.end;
                }

                break;


            case Missile_state.end:

                break;
        }
    }
}