lvjincheng_smartbowsdkdemo/Assets/Demo/Scripts/Arrow.cs

using System.Collections;
using UnityEngine;

public class Arrow : MonoBehaviour
{
    void Start()
    {
        StartCoroutine(DestroySelf());
    }

    void Update()
    {
        this.transform.position += transform.forward * Time.deltaTime * 10f;
    }

    IEnumerator DestroySelf()
    {
        yield return new WaitForSeconds(3f);
        Destroy(gameObject);
    }
}