应该是unity 2018.3中加入的功能，对象可以放置于不同的物理场景中。

一个Scene对应一个物理场景(PhysicsScene)，若想放入独立的物理场景测试创建一个Scene即可。见下图gif。

 

若测试模拟功能，须在Physics中关闭自动模拟。脚本如下：

using System.Collections;using System.Collections.Generic;using UnityEngine;using UnityEngine.SceneManagement;public class PhysicsSceneDemo : MonoBehaviour{    public GameObject[] simulationObjects;    public float physicsSceneTime;    float mLastPhysicsSceneTime;    Scene mPhysicsTestScene;    PhysicsScene mPhysicsScene;    void Start()    {        mPhysicsTestScene = SceneManager.CreateScene("PhysicsTestScene");        mPhysicsScene = mPhysicsTestScene.GetPhysicsScene();        for (int i = 0; i < simulationObjects.Length; i++)            SceneManager.MoveGameObjectToScene(simulationObjects[i], mPhysicsTestScene);        Physics.autoSimulation = false;    }    void Update()    {        if (physicsSceneTime != mLastPhysicsSceneTime)        {            mPhysicsScene.Simulate(physicsSceneTime);            mLastPhysicsSceneTime = physicsSceneTime;        }    }    void OnDestroy()    {        SceneManager.UnloadSceneAsync(mPhysicsTestScene);        Physics.autoSimulation = true;    }}

 

测试仓库：