三维扫描仪[11]——总结并展望基于Kinect的三维扫描仪

到这里，我相信绝大多数大一的相关专业学生都可以完成这样一台扫描仪了。
让我们全局看一下这个小项目。

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机械方面
可以参考三维扫描仪[8]——如何设计一台云台式扫描仪（机械结构）



我们需要一个支架，支起Kinect和云台，同时我们也需要一套齿轮组，获得精确的角度变化。

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开发环境方面
可以参考：
三维扫描仪[6]——常用软件及开发环境
三维扫描仪[7]——认识Processing和Arduino开发环境
其中

Meshlab

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Arduino

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Processing
和其他的中间件是必须的

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项目代码方面
可以参考：
三维扫描仪[9]——如何设计一台云台式扫描仪（初步软件设计）
三维扫描仪[10]——如何设计一台云台式扫描仪（代码详解）
这里也附上全套代码
Arduino
步进电机代码

int xdir = 13;
int Step = 12;
int xen = 9;

void setup() {
  // put your setup code here, to run once:
  pinMode(xen, OUTPUT);
  pinMode(xdir, OUTPUT);
  pinMode(Step, OUTPUT);
  digitalWrite(xen, LOW);
  digitalWrite(xdir, LOW);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(Step, LOW);
  delay(10);
  digitalWrite(Step, HIGH);
  delay(10);
}

角度传感器代码

int potPin = A0;
int Pos = 0;

void setup() {
  // put your setup code here, to run once:
  pinMode(potPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  Pos = analogRead(potPin);
  delay(250);
  Serial.println(Pos);
}

Processing

import processing.serial.*;
import processing.opengl.*;
import SimpleOpenNI.*;
import kinectOrbit.*;
//Init Orbit and OpenNI Class.
KinectOrbit myOrbit;
SimpleOpenNI kinect;
//Serial data.
Serial myPort;
boolean serial = true;
//!
String turnTableAngle = "0";
int turnAngle = 0;
float Angle = 0;
//!
//Init pointClouds and ArrayList with clolors.
ArrayList scanPoints = new ArrayList();//pointCloud
ArrayList scanColors = new ArrayList();//obj color
ArrayList objectPoints = new ArrayList();//pointCloud
ArrayList objectColors = new ArrayList();//obj color

//Height
float baseHeight  = -180;
float modelWidth  = 1000;
float modelHeight = 1000;
PVector axis = new PVector(0, baseHeight, 1200);

int scanLines = 300;
int scanRes   = 1;  //high ppx
boolean scanning = false;
boolean arrived  = false;
float[] shotNumber = new float[30];
int currentShot = 0;

int dataNum = 1;

public void setup()
{
  size(800, 600, OPENGL);

  //Init orbit
  myOrbit = new KinectOrbit(this, 0, "kinect");
  myOrbit.drawCS(true);
  myOrbit.drawGizmo(true);
  myOrbit.setCSScale(200);
  myOrbit.drawGround(true);

  //Init SimpleOpenNI
  kinect = new SimpleOpenNI(this);
  kinect.setMirror(false);
  kinect.enableDepth();
  kinect.enableRGB();
  kinect.alternativeViewPointDepthToImage();

  //Serial
  if(serial) {
    String portName = Serial.list()[0];
    myPort = new Serial(this, portName, 9600);
    //!
    myPort.bufferUntil('\n');
    //!
  }
}

public void draw()
{
  kinect.update();
  background(0);
  myOrbit.pushOrbit(this);  //Start Orbit
  drawPointCloud(1);
  //!!!!!
  updateObject(scanLines, scanRes);
  //!!!!!
  drawObjects();
  drawBoundingBox();
  kinect.drawCamFrustum();
  myOrbit.popOrbit(this);
}






void drawPointCloud(int steps)
{
  int index;
  PVector realWorldPoint;
  stroke(255);

  for(int y = 0; y < kinect.depthHeight(); y += steps) {
    for(int x = 0; x < kinect.depthWidth(); x += steps) {
      index = x + y * kinect.depthWidth();
      realWorldPoint = kinect.depthMapRealWorld()[index];
      stroke(150);
      point(realWorldPoint.x, realWorldPoint.y, realWorldPoint.z);
    }
  }
}

void drawObjects()
{
  pushStyle();
  strokeWeight(1);

  for(int i = 1; i < objectPoints.size(); i++) {
    stroke(objectColors.get(i).x, objectColors.get(i).y, objectColors.get(i).z);
    point(objectPoints.get(i).x, objectPoints.get(i).y, objectPoints.get(i).z + axis.z);
  }
  for(int i = 1; i < scanPoints.size(); i++) {
    stroke(scanColors.get(i).x, scanColors.get(i).y, scanColors.get(i).z);
    point(scanPoints.get(i).x, scanPoints.get(i).y, scanPoints.get(i).z + axis.z);
  }
  popStyle();  
}

void drawBoundingBox()
{
  stroke(255, 0, 0);
  line(axis.x, axis.y, axis.z, axis.x, axis.y+100, axis.z);
  noFill();
  pushMatrix();
  translate(axis.x, axis.x + baseHeight + (modelHeight / 2), axis.z);
  box(modelWidth, modelHeight, modelWidth);
  popMatrix();
}

void scan()
{
  for(PVector v : scanPoints) {
    objectPoints.add(v.get());
    int index = scanPoints.indexOf(v);
    objectColors.add(scanColors.get(index).get());
  }
  if(currentShot < shotNumber.length-1) {
    currentShot ++;
    println("scan angle = " + Angle);
  }
  else {
    scanning = false;
  }
  arrived = false;
}

void updateObject(int scanWidth, int step)
{
  int index;
  PVector realWorldPoint;
  scanPoints.clear();
  scanColors.clear();
  serialEvent(myPort);
  Angle = radians(map(turnAngle, 0, 1023, 0, 360));
  //println("angle = " + Angle);
  //draw line
  pushMatrix();
  translate(axis.x, axis.y, axis.z);
  rotateY(Angle);
  line(0, 0, 100, 0);
  popMatrix();

  int xMin = (int)(kinect.depthWidth() / 2 - scanWidth / 2);
  int xMax = (int)(kinect.depthWidth() / 2 + scanWidth / 2);
  for(int y = 0; y < kinect.depthHeight(); y += step) {
    for(int x = xMin; x < xMax; x += step) {
      index = x + (y * kinect.depthWidth());
      realWorldPoint = kinect.depthMapRealWorld()[index];
      color pointCol = kinect.rgbImage().pixels[index];

      if(realWorldPoint.y < (modelHeight + baseHeight) && realWorldPoint.y > baseHeight) {
        if(abs(realWorldPoint.x - axis.x) < modelWidth / 2) {
          if(realWorldPoint.z < axis.z + modelWidth / 2 && realWorldPoint.z > axis.z - modelWidth / 2) {
            PVector rotatedPoint;
            realWorldPoint.z -= axis.z;
            realWorldPoint.x -= axis.x;
            rotatedPoint = vecRotY(realWorldPoint, Angle);

            scanPoints.add(rotatedPoint.get());
            scanColors.add(new PVector(red(pointCol), green(pointCol), blue(pointCol)));
          }
        }
      }
    }
  }
}

PVector vecRotY(PVector vecIn, float phi)
{
  PVector rotatedVec = new PVector();
  rotatedVec.x = vecIn.x * cos(phi) - vecIn.z * sin(phi);
  rotatedVec.z = vecIn.x * sin(phi) + vecIn.z * cos(phi);
  rotatedVec.y = vecIn.y;
  return rotatedVec;
}

public void keyPressed()
{
  switch(key) {
    case 'c':
      objectPoints.clear();
      objectColors.clear();
      currentShot = 0;
      break;
    case 'e':
      String stringNum = String.valueOf(dataNum);
      char key = stringNum.charAt(0);
      exportPly(key);
      dataNum ++;
      println("save success!");
      break;
    case 's':
      scan();
      break;
  }
}

public void serialEvent(Serial myPort)
{
  String inString = myPort.readStringUntil('\n');
  if(inString != null) {
    //cut space
    turnTableAngle = trim(inString);
    turnAngle = Integer.parseInt(turnTableAngle);
  }
}

void exportPly(char key)
{
  PrintWriter output;
  String viewPointFileName;
  viewPointFileName = "myPoints" + key + ".ply";
  output = createWriter(dataPath(viewPointFileName));

  //!!!!
  //head file
  output.println("ply");
  output.println("format ascii 1.0");
  output.println("comment This is your Processing ply file");
  output.println("element vertex " + (objectPoints.size()-1));
  output.println("property float x");
  output.println("property float y");
  output.println("property float z");
  output.println("property uchar red");
  output.println("property uchar green");
  output.println("property uchar blue");
  output.println("end_header");
  //!!!!

  for(int i = 0; i < objectPoints.size() - 1; i++) {
    output.println(
      (objectPoints.get(i).x / 1000) + " "
      + (objectPoints.get(i).y / 1000) + " "
      + (objectPoints.get(i).z / 1000) + " "
      + (int) objectColors.get(i).x + " "
      + (int) objectColors.get(i).y + " "
      + (int) objectColors.get(i).z
    );
  }

  output.flush();
  output.close();
}

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三维重建原理方面
可以参考：
三维扫描仪[2]——大恒、微软、还是淘宝一下双目摄像头？
三维扫描仪[3]——标定·理论

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本项目并不涉及、但是接下来会用到的标定方面
可以参考：
三维扫描仪[4]——标定·Matlab单目标定
三维扫描仪[5]——标定·Matlab双目标定

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展望
本来没有这个部分的
然而我昨天（2017.4.21）散步的时候突然想到：
用两个Kinect
KinectA保持不动 KinectB在A的视野下运动 由KinectB扫描
我们需要确定A的空间位置 获得B实时的空间位置和角度
最终！根据多个空间坐标系的转换 实现手持Kinect扫描并叠加
没有实验过，也没考虑过优势。
只是作为一个二本大三的软件工程学生，感觉扫描仪再贴点，再有庞杂的机械结构，挺不好的。
希望廉价的扫描仪能服务更多的普通人吧。
希望我将来去漫展的时候，真的能把你们变成我的手办。

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扫描仪这个部分并没有结束。
这只是一个小例子，用来体会逆向工程的。
接下来我们干个酷炫的
要不这几年真白读了