为什么我导入的模型移动这么小，与 cannon.js 的物理相比较？

Question

我想创建一个车辆，它在 three.js 和 cannon.js 中四处移动。但是当我更新 three.js 模型的位置时，它也向后移动得很少我不知道是什么导致了这个问题？是秤吗？？

我删除了相机、渲染器等不必要的 three.js 部分......所以它更容易阅读。如果你想试试我可以提供整个代码。

import * as THREE from 'three'
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
import * as CANNON from 'cannon-es'
import CannonDebugger from 'cannon-es-debugger'
import {GLTFLoader} from 'three/examples/jsm/loaders/GLTFLoader'

const gltfLoader = new GLTFLoader(loadingManager)
const rover_group = new THREE.Group();
const rover = []

const seda= new THREE.MeshPhongMaterial()
gltfLoader.load('./models/Rover.gltf', function(model) { //VELKEJ
    model.scene.traverse(part => {
        rover.push(part)
        part.receiveShadow = true
        part.castShadow = true 

        if (part.isMesh) {  
            if(part.name == 'Kolo1') {
                part.material = seda
            }
            if(part.name == 'Kolo2') {
                part.material = seda
            }
            if(part.name == 'Kolo3') {
                part.material = seda
            }
            if(part.name == 'Kolo4') {
                part.material = seda
            }
            if(part.name == 'Rover') part.material = seda
        }
        
    });
    rover.forEach(part => {
        rover_group.add(part)
    })
    rover_group.scale.set(0.004,0.004,0.004)
    rover_group.children[1].position.x = -4 
    rover_group.rotation.set(0,Math.PI,0)
    scene.add(rover_group)
    console.log(rover_group)
})


//CANNON WORLD
const physicsWorld = new CANNON.World({
    gravity: new CANNON.Vec3(0, -9.82, 0)
})

//Floor
const groundBody = new CANNON.Body ({ 
    type: CANNON.Body.STATIC, 
    shape: new CANNON.Plane()
});

// rotate ground body by 90 degrees 
groundBody.quaternion.setFromEuler(-Math.PI/2, 0, 0);
//Add to floor to scene
physicsWorld.addBody (groundBody);

//Create a cannon.js car body

//Cannon.js body
const carBody = new CANNON.Body({
    mass: 20,
    position: new CANNON. Vec3(0, 6, 0), 
    shape: new CANNON.Box (new CANNON. Vec3(0.8, 0.1, 0.4)),
})
const vehicle = new CANNON.RigidVehicle({
    chassisBody: carBody
})


const mass = 1;
const axisWidth = 0.2;
const wheelShape = new CANNON.Sphere(0.2);
const wheelMaterial = new CANNON.Material('wheel');
const down = new CANNON.Vec3(0, -1, 0);

//Wheel front left
const wheelBody1 = new CANNON.Body({ mass, material: wheelMaterial });
wheelBody1.addShape(wheelShape);
wheelBody1.angularDamping = 0.4;
vehicle.addWheel({
    body: wheelBody1, 
    position: new CANNON.Vec3(-0.4, 0, axisWidth / 0.4),
    axis: new CANNON.Vec3(0, 0, 1),
    direction: down,
})

//Wheel front right
const wheelBody2 = new CANNON.Body({ mass, material: wheelMaterial });
wheelBody2.addShape(wheelShape);
wheelBody2.angularDamping = 0.4;
vehicle.addWheel({
    body: wheelBody2, 
    position: new CANNON.Vec3(-0.4, 0, -axisWidth / 0.4),
    axis: new CANNON.Vec3(0, 0, 1),
    direction: down,
})
//Wheel back right
const wheelBody3 = new CANNON.Body({ mass, material: wheelMaterial });
wheelBody3.addShape(wheelShape);
wheelBody3.angularDamping = 0.4;
vehicle.addWheel({
    body: wheelBody3, 
    position: new CANNON.Vec3(0.4, 0, -axisWidth / 0.4),
    axis: new CANNON.Vec3(0, 0, 1),
    direction: down,
})

//Wheel back left
const wheelBody4 = new CANNON.Body({ mass, material: wheelMaterial });
wheelBody4.addShape(wheelShape);
wheelBody4.angularDamping = 0.4;
vehicle.addWheel({
    body: wheelBody4, 
    position: new CANNON.Vec3(0.4, 0, axisWidth / 0.4),
    axis: new CANNON.Vec3(0, 0, 1),
    direction: down,
})
vehicle.addToWorld(physicsWorld)


//Debugger


const cannonDebuger = new CannonDebugger(scene, physicsWorld)

const clock = new THREE.Clock()
let oldElapsedTime = 0

//Animate
const Animate = () => {
    const elapsedTime = clock.getElapsedTime()
    const deltaTime = elapsedTime - oldElapsedTime
    oldElapsedTime = elapsedTime

    //Update physics world
    physicsWorld.step(1 / 60, deltaTime, 3)

    rover_group.children[1].position.copy(carBody.position)
    rover_group.children[1].quaternion.copy(carBody.quaternion)
    ///////LEFT FRONT
    rover_group.children[5].position.copy(wheelBody1.position)
    rover_group.children[5].quaternion.copy(wheelBody1.quaternion)
    ///////RIGHT FRONT
    rover_group.children[2].position.copy(wheelBody2.position)
    rover_group.children[2].quaternion.copy(wheelBody2.quaternion)
    ////////LEFT BACK
    rover_group.children[4].position.copy(wheelBody4.position)
    rover_group.children[4].quaternion.copy(wheelBody4.quaternion)
      //////RIGHT BACK
    rover_group.children[3].position.copy(wheelBody4.position)
    rover_group.children[3].position.copy(wheelBody4.quaternion)


    cannonDebuger.update()
    window.requestAnimationFrame(Animate)

     // Update controls
     controls.update()

     // Render
     renderer.render(scene, camera)
}
Animate()