pick + pdcontrol

pick & place

by Rebecca Chen

HTML

<div id="info">Pick & Place</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/84/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js">


</script>

CSS

#info {
  position: absolute;
  top: 0px;
  width: 100%;
  padding: 10px;
  text-align: center;
  color: #ffff00
}

body {
  overflow: hidden
}

JavaScript

class PDController {
	constructor (x=0, xref=0) {
  	this.x = x;
    this.xref = xref;
    this.v = 0;
    this.KP = 150;   // 'spring constant'
    this.KD = 20;   // 'damping'
  }
  
  update (dt) {
  	let f = -this.KP * (this.x-this.xref) - this.KD*this.v;
    this.v += f*dt;
    this.x += this.v*dt
    return this.x
  }
  setRef (ref) {
  	this.xref = ref;
  }
}

var camera, scene, renderer, controls;
var mark;

var raycaster;
var mouse = new THREE.Vector2();
var pickables = [];
var clock, pdcontrol;

init();
animate();

function init() {
  scene = new THREE.Scene();

  camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 1000);
  camera.position.z = 500;

  var gridXZ = new THREE.GridHelper(200, 20, 'red', 'white');
  scene.add(gridXZ);

  renderer = new THREE.WebGLRenderer();
  renderer.setSize(window.innerWidth, window.innerHeight);
  renderer.setClearColor(0x888888);

  controls = new THREE.OrbitControls(camera, renderer.domElement);

  document.body.appendChild(renderer.domElement);

  /////////////////////////////////////////////////////////////////////
  plane = new THREE.Mesh(new THREE.PlaneGeometry(200, 200), new THREE.MeshBasicMaterial({
    transparent: true,
    opacity: 0.1,
    visible: true
  }));
  scene.add(plane);
  plane.rotation.x = -Math.PI / 2;
  pickables = [plane];

  mark = new THREE.Mesh(new THREE.BoxGeometry(3, 2, 20), new THREE.MeshNormalMaterial());
  scene.add(mark);
  mark.position.set (-80, 0, -50)

  raycaster = new THREE.Raycaster();
  document.addEventListener('mousedown', onDocumentMouseDown, false);

	/////////////
  let geometry = new THREE.Geometry();  // [-80,80]
  geometry.vertices.push (new THREE.Vector3(-80, 0, -50));
  geometry.vertices.push (new THREE.Vector3(80, 0, -50));  
  let line = new THREE.Line (geometry, new THREE.LineBasicMaterial ({color:0xff00ff}))
  scene.add (line)
  
  pdcontrol = new PDController();
  clock = new THREE.Clock()

	puck = new THREE.Mesh(new...