Building the device

Arduino-Radar-Cardboard-Stand

Arduino-Radar-Pin-Hearder

Arduino-Radar-Complete

Circuit Schematics

I connected the Ultrasonic Sensor HC-SR04 to the pins number 10 and 11 and the servo motor to the pin number 12 on the Arduino Board.

Arduino-Radar-Circuit-Schematics

Source codes

Now we need to make a code and upload it to the Arduino Board that will enable the interaction between the Arduino and the Processing IDE. For understanding how the connection works click here to visit my Arduino and Processing Tutorial.

Arduino-and-Processing-IDE

Here’s the Arduino Source Code with description of each line of the code:
  1. // Includes the Servo library
    #include <Servo.h>.
    // Defines Tirg and Echo pins of the Ultrasonic Sensor
    const int trigPin = 10;
    const int echoPin = 11;
    // Variables for the duration and the distance
    long duration;
    int distance;
    Servo myServo; // Creates a servo object for controlling the servo motor
    void setup() {
    pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
    pinMode(echoPin, INPUT); // Sets the echoPin as an Input
    Serial.begin(9600);
    myServo.attach(12); // Defines on which pin is the servo motor attached
    }
    void loop() {
    // rotates the servo motor from 15 to 165 degrees
    for(int i=15;i<=165;i++){
    myServo.write(i);
    delay(30);
    distance = calculateDistance();// Calls a function for calculating the distance measured by the Ultrasonic sensor for each degree
    Serial.print(i); // Sends the current degree into the Serial Port
    Serial.print(","); // Sends addition character right next to the previous value needed later in the Processing IDE for indexing
    Serial.print(distance); // Sends the distance value into the Serial Port
    Serial.print("."); // Sends addition character right next to the previous value needed later in the Processing IDE for indexing
    }
    // Repeats the previous lines from 165 to 15 degrees
    for(int i=165;i>15;i--){
    myServo.write(i);
    delay(30);
    distance = calculateDistance();
    Serial.print(i);
    Serial.print(",");
    Serial.print(distance);
    Serial.print(".");
    }
    }
    // Function for calculating the distance measured by the Ultrasonic sensor
    int calculateDistance(){
    digitalWrite(trigPin, LOW);
    delayMicroseconds(2);
    // Sets the trigPin on HIGH state for 10 micro seconds
    digitalWrite(trigPin, HIGH);
    delayMicroseconds(10);
    digitalWrite(trigPin, LOW);
    duration = pulseIn(echoPin, HIGH); // Reads the echoPin, returns the sound wave travel time in microseconds
    distance= duration*0.034/2;
    return distance;
    }

Now we will receive the values for the angle and the distance measured by the sensor from the Arduino Board into the Processing IDE using the SerialEvent() function which reads the data from the Serial Port and we will put the values of the angle and the distance into the variables iAngle and iDistance. These variable will be used for drawing the radar, the lines, the detected objects and some of the text.

Radar-Print-Screen-02

For drawing the radar I made this function drawRadar() which consist of arc() and line() functions.

  1. void drawRadar() {
    pushMatrix();
    translate(960,1000); // moves the starting coordinats to new location
    noFill();
    strokeWeight(2);
    stroke(98,245,31);
    // draws the arc lines
    arc(0,0,1800,1800,PI,TWO_PI);
    arc(0,0,1400,1400,PI,TWO_PI);
    arc(0,0,1000,1000,PI,TWO_PI);
    arc(0,0,600,600,PI,TWO_PI);
    // draws the angle lines
    line(-960,0,960,0);
    line(0,0,-960*cos(radians(30)),-960*sin(radians(30)));
    line(0,0,-960*cos(radians(60)),-960*sin(radians(60)));
    line(0,0,-960*cos(radians(90)),-960*sin(radians(90)));
    line(0,0,-960*cos(radians(120)),-960*sin(radians(120)));
    line(0,0,-960*cos(radians(150)),-960*sin(radians(150)));
    line(-960*cos(radians(30)),0,960,0);
    popMatrix();
    }

Radar-Print-Screen-03

For drawing the line that is moving along the radar I made this function drawLine(). Its center of rotation is set with the translate() function and using the line() function in which the iAngle variable is used the line is redrawn for each degree.

void drawLine() {
pushMatrix();
strokeWeight(9);
stroke(30,250,60);
translate(960,1000); // moves the starting coordinats to new location
line(0,0,950*cos(radians(iAngle)),-950*sin(radians(iAngle))); // draws the line according to the angle
popMatrix();
}

Radar-Print-Screen-04

For drawing the detected objects I made this drawObject() function. It gets the distance from ultrasonic sensor, transforms it into pixels and in combination with the angle of the sensor draws the object on the radar.

void drawObject() {
pushMatrix();
translate(960,1000); // moves the starting coordinats to new location
strokeWeight(9);
stroke(255,10,10); // red color
pixsDistance = iDistance*22.5; // covers the distance from the sensor from cm to pixels
// limiting the range to 40 cms
if(iDistance<40){
// draws the object according to the angle and the distance
line(pixsDistance*cos(radians(iAngle)),-pixsDistance*sin(radians(iAngle)),950*cos(radians(iAngle)),-950*sin(radians(iAngle)));
}
popMatrix();
}

For the text on the screen I made the drawText() function which draws texts on particular locations.

All of these functions are called in the main draw() function which repeats all the time and draws the screen. Also here I am using this fill() function with 2 parameters for simulating motion blur and slow fade of the moving line.

void draw() {
fill(98,245,31);
textFont(orcFont);
// simulating motion blur and slow fade of the moving line
noStroke();
fill(0,4);
rect(0, 0, width, 1010);
fill(98,245,31); // green color
// calls the functions for drawing the radar
drawRadar();
drawLine();
drawObject();
drawText();
}

Here’s the final appearance of the radar:

Arduino Radar Final Appearance

Here’s the complete Processing Source Code of the Arduino Radar:

  1. import processing.serial.*; // imports library for serial communication
    import java.awt.event.KeyEvent; // imports library for reading the data from the serial port
    import java.io.IOException;
    Serial myPort; // defines Object Serial
    // defubes variables
    String angle="";
    String distance="";
    String data="";
    String noObject;
    float pixsDistance;
    int iAngle, iDistance;
    int index1=0;
    int index2=0;
    PFont orcFont;
    void setup() {
    size (1920, 1080);
    smooth();
    myPort = new Serial(this,"COM4", 9600); // starts the serial communication
    myPort.bufferUntil('.'); // reads the data from the serial port up to the character '.'. So actually it reads this: angle,distance.
    orcFont = loadFont("OCRAExtended-30.vlw");
    }
    void draw() {
    fill(98,245,31);
    textFont(orcFont);
    // simulating motion blur and slow fade of the moving line
    noStroke();
    fill(0,4);
    rect(0, 0, width, 1010);
    fill(98,245,31); // green color
    // calls the functions for drawing the radar
    drawRadar();
    drawLine();
    drawObject();
    drawText();
    }
    void serialEvent (Serial myPort) { // starts reading data from the Serial Port
    // reads the data from the Serial Port up to the character '.' and puts it into the String variable "data".
    data = myPort.readStringUntil('.');
    data = data.substring(0,data.length()-1);
    index1 = data.indexOf(","); // find the character ',' and puts it into the variable "index1"
    angle= data.substring(0, index1); // read the data from position "0" to position of the variable index1 or thats the value of the angle the Arduino Board sent into the Serial Port
    distance= data.substring(index1+1, data.length()); // read the data from position "index1" to the end of the data pr thats the value of the distance
    // converts the String variables into Integer
    iAngle = int(angle);
    iDistance = int(distance);
    }
    void drawRadar() {
    pushMatrix();
    translate(960,1000); // moves the starting coordinats to new location
    noFill();
    strokeWeight(2);
    stroke(98,245,31);
    // draws the arc lines
    arc(0,0,1800,1800,PI,TWO_PI);
    arc(0,0,1400,1400,PI,TWO_PI);
    arc(0,0,1000,1000,PI,TWO_PI);
    arc(0,0,600,600,PI,TWO_PI);
    // draws the angle lines
    line(-960,0,960,0);
    line(0,0,-960*cos(radians(30)),-960*sin(radians(30)));
    line(0,0,-960*cos(radians(60)),-960*sin(radians(60)));
    line(0,0,-960*cos(radians(90)),-960*sin(radians(90)));
    line(0,0,-960*cos(radians(120)),-960*sin(radians(120)));
    line(0,0,-960*cos(radians(150)),-960*sin(radians(150)));
    line(-960*cos(radians(30)),0,960,0);
    popMatrix();
    }
    void drawObject() {
    pushMatrix();
    translate(960,1000); // moves the starting coordinats to new location
    strokeWeight(9);
    stroke(255,10,10); // red color
    pixsDistance = iDistance*22.5; // covers the distance from the sensor from cm to pixels
    // limiting the range to 40 cms
    if(iDistance<40){
    // draws the object according to the angle and the distance
    line(pixsDistance*cos(radians(iAngle)),-pixsDistance*sin(radians(iAngle)),950*cos(radians(iAngle)),-950*sin(radians(iAngle)));
    }
    popMatrix();
    }
    void drawLine() {
    pushMatrix();
    strokeWeight(9);
    stroke(30,250,60);
    translate(960,1000); // moves the starting coordinats to new location
    line(0,0,950*cos(radians(iAngle)),-950*sin(radians(iAngle))); // draws the line according to the angle
    popMatrix();
    }
    void drawText() { // draws the texts on the screen
    pushMatrix();
    if(iDistance>40) {
    noObject = "Out of Range";
    }
    else {
    noObject = "In Range";
    }
    fill(0,0,0);
    noStroke();
    rect(0, 1010, width, 1080);
    fill(98,245,31);
    textSize(25);
    text("10cm",1180,990);
    text("20cm",1380,990);
    text("30cm",1580,990);
    text("40cm",1780,990);
    textSize(40);
    text("Object: " + noObject, 240, 1050);
    text("Angle: " + iAngle +" °", 1050, 1050);
    text("Distance: ", 1380, 1050);
    if(iDistance<40) {
    text(" " + iDistance +" cm", 1400, 1050);
    }
    textSize(25);
    fill(98,245,60);
    translate(961+960*cos(radians(30)),982-960*sin(radians(30)));
    rotate(-radians(-60));
    text("30°",0,0);
    resetMatrix();
    translate(954+960*cos(radians(60)),984-960*sin(radians(60)));
    rotate(-radians(-30));
    text("60°",0,0);
    resetMatrix();
    translate(945+960*cos(radians(90)),990-960*sin(radians(90)));
    rotate(radians(0));
    text("90°",0,0);
    resetMatrix();
    translate(935+960*cos(radians(120)),1003-960*sin(radians(120)));
    rotate(radians(-30));
    text("120°",0,0);
    resetMatrix();
    translate(940+960*cos(radians(150)),1018-960*sin(radians(150)));
    rotate(radians(-60));
    text("150°",0,0);
    popMatrix();
    }

New Updated version of the code to fit any screen resolution

Just change the values in size() function, with your screen resolution.

  1. /* Arduino Radar Project
    *
    * Updated version. Fits any screen resolution!
    * Just change the values in the size() function,
    * with your screen resolution.
    *
    * by Dejan Nedelkovski,
    * www.HowToMechatronics.com
    *
    */
    import processing.serial.*; // imports library for serial communication
    import java.awt.event.KeyEvent; // imports library for reading the data from the serial port
    import java.io.IOException;
    Serial myPort; // defines Object Serial
    // defubes variables
    String angle="";
    String distance="";
    String data="";
    String noObject;
    float pixsDistance;
    int iAngle, iDistance;
    int index1=0;
    int index2=0;
    PFont orcFont;
    void setup() {
    size (1920, 1080); // ***CHANGE THIS TO YOUR SCREEN RESOLUTION***
    smooth();
    myPort = new Serial(this,"COM4", 9600); // starts the serial communication
    myPort.bufferUntil('.'); // reads the data from the serial port up to the character '.'. So actually it reads this: angle,distance.
    orcFont = loadFont("OCRAExtended-30.vlw");
    }
    void draw() {
    fill(98,245,31);
    textFont(orcFont);
    // simulating motion blur and slow fade of the moving line
    noStroke();
    fill(0,4);
    rect(0, 0, width, height-height*0.065);
    fill(98,245,31); // green color
    // calls the functions for drawing the radar
    drawRadar();
    drawLine();
    drawObject();
    drawText();
    }
    void serialEvent (Serial myPort) { // starts reading data from the Serial Port
    // reads the data from the Serial Port up to the character '.' and puts it into the String variable "data".
    data = myPort.readStringUntil('.');
    data = data.substring(0,data.length()-1);
    index1 = data.indexOf(","); // find the character ',' and puts it into the variable "index1"
    angle= data.substring(0, index1); // read the data from position "0" to position of the variable index1 or thats the value of the angle the Arduino Board sent into the Serial Port
    distance= data.substring(index1+1, data.length()); // read the data from position "index1" to the end of the data pr thats the value of the distance
    // converts the String variables into Integer
    iAngle = int(angle);
    iDistance = int(distance);
    }
    void drawRadar() {
    pushMatrix();
    translate(width/2,height-height*0.074); // moves the starting coordinats to new location
    noFill();
    strokeWeight(2);
    stroke(98,245,31);
    // draws the arc lines
    arc(0,0,(width-width*0.0625),(width-width*0.0625),PI,TWO_PI);
    arc(0,0,(width-width*0.27),(width-width*0.27),PI,TWO_PI);
    arc(0,0,(width-width*0.479),(width-width*0.479),PI,TWO_PI);
    arc(0,0,(width-width*0.687),(width-width*0.687),PI,TWO_PI);
    // draws the angle lines
    line(-width/2,0,width/2,0);
    line(0,0,(-width/2)*cos(radians(30)),(-width/2)*sin(radians(30)));
    line(0,0,(-width/2)*cos(radians(60)),(-width/2)*sin(radians(60)));
    line(0,0,(-width/2)*cos(radians(90)),(-width/2)*sin(radians(90)));
    line(0,0,(-width/2)*cos(radians(120)),(-width/2)*sin(radians(120)));
    line(0,0,(-width/2)*cos(radians(150)),(-width/2)*sin(radians(150)));
    line((-width/2)*cos(radians(30)),0,width/2,0);
    popMatrix();
    }
    void drawObject() {
    pushMatrix();
    translate(width/2,height-height*0.074); // moves the starting coordinats to new location
    strokeWeight(9);
    stroke(255,10,10); // red color
    pixsDistance = iDistance*((height-height*0.1666)*0.025); // covers the distance from the sensor from cm to pixels
    // limiting the range to 40 cms
    if(iDistance<40){
    // draws the object according to the angle and the distance
    line(pixsDistance*cos(radians(iAngle)),-pixsDistance*sin(radians(iAngle)),(width-width*0.505)*cos(radians(iAngle)),-(width-width*0.505)*sin(radians(iAngle)));
    }
    popMatrix();
    }
    void drawLine() {
    pushMatrix();
    strokeWeight(9);
    stroke(30,250,60);
    translate(width/2,height-height*0.074); // moves the starting coordinats to new location
    line(0,0,(height-height*0.12)*cos(radians(iAngle)),-(height-height*0.12)*sin(radians(iAngle))); // draws the line according to the angle
    popMatrix();
    }
    void drawText() { // draws the texts on the screen
    pushMatrix();
    if(iDistance>40) {
    noObject = "Out of Range";
    }
    else {
    noObject = "In Range";
    }
    fill(0,0,0);
    noStroke();
    rect(0, height-height*0.0648, width, height);
    fill(98,245,31);
    textSize(25);
    text("10cm",width-width*0.3854,height-height*0.0833);
    text("20cm",width-width*0.281,height-height*0.0833);
    text("30cm",width-width*0.177,height-height*0.0833);
    text("40cm",width-width*0.0729,height-height*0.0833);
    textSize(40);
    text("Object: " + noObject, width-width*0.875, height-height*0.0277);
    text("Angle: " + iAngle +" °", width-width*0.48, height-height*0.0277);
    text("Distance: ", width-width*0.26, height-height*0.0277);
    if(iDistance<40) {
    text(" " + iDistance +" cm", width-width*0.225, height-height*0.0277);
    }
    textSize(25);
    fill(98,245,60);
    translate((width-width*0.4994)+width/2*cos(radians(30)),(height-height*0.0907)-width/2*sin(radians(30)));
    rotate(-radians(-60));
    text("30°",0,0);
    resetMatrix();
    translate((width-width*0.503)+width/2*cos(radians(60)),(height-height*0.0888)-width/2*sin(radians(60)));
    rotate(-radians(-30));
    text("60°",0,0);
    resetMatrix();
    translate((width-width*0.507)+width/2*cos(radians(90)),(height-height*0.0833)-width/2*sin(radians(90)));
    rotate(radians(0));
    text("90°",0,0);
    resetMatrix();
    translate(width-width*0.513+width/2*cos(radians(120)),(height-height*0.07129)-width/2*sin(radians(120)));
    rotate(radians(-30));
    text("120°",0,0);
    resetMatrix();
    translate((width-width*0.5104)+width/2*cos(radians(150)),(height-height*0.0574)-width/2*sin(radians(150)));
    rotate(radians(-60));
    text("150°",0,0);
    popMatrix();
    }