Intel Edison: Distance Bug - HC-SR04

Say hello to the distance bug!

The basic idea in this project is that it measures distance with ultrasound and displays it in centimeters to the LCD display. Bonus feature is that if the button is pushed the LCD will turn green and it will save the current distance to the SD card. On the screen it will say "Saved to SD card".

There is also a feature if the measurement is too close or too far it will display "Out of range".

The measurements are also recorded by serial monitor or if you want use it with 9 V battery and it will become portable.

Project is fairly easy to do.

Basic Components.

This project is done with Intel Edison board.

This can be done with any Arduino board available.

I'm using a connector shield over the board.

You will also need two basic cables to the shield and one modified cable.

Then you will need a push button, RGB-LCD screen, A micro SD card and a distance sensor (HC-SR04)

Modding the Cable.

This is very simple to do.

Just solder 4 wires to a connector that you can connect to the HC-SR04.

Just make sure that the wires are in right order. That means basicly that the Vcc and the GND must be in the right place. The Trigger and Echo can be coded on the board so that is not very critical how they are in the connector.

Connecting and Coding.

Connect the pieces to the board like in the picture and connect the board to the PC.

Open your coding program and start coding.

First Define the needed components and global variables.

#define echoPin 7 
#define trigPin 8 
#define LEDPin 13 
#include 
#include "rgb_lcd.h"
#include 
const int chipSelect = 4;
rgb_lcd lcd;
const int colorR = 255;
const int colorG = 255;
const int colorB = 255;
int maximumRange = 400; 
int minimumRange = 0; 
long duration, distance; 
const int pinButton = 3;

Then start with void setup.

Open serial with Serial.begin(115200); and set the LCD and the colors. then set the Trigger and echo pin for the distance censor. Lastly select the SD card for saving data.

void setup() {
 Serial.begin (115200);
 
 
 pinMode(pinButton, INPUT);
 
 lcd.begin(16, 2);
 lcd.setRGB(colorR, colorG, colorB);
 pinMode(trigPin, OUTPUT);
 pinMode(echoPin, INPUT);
 pinMode(LEDPin, OUTPUT); 
 
    Serial.print("Start write to card.");
 
  if (!SD.begin(chipSelect)) {
    Serial.println("No card or failure");
   
    return;
  }
  Serial.println("Card found");
}

Then start working with Void loop.

this is the main program that will loop to infinity.

The trigger pin sends the ultrasound and the sound is returned to the echo pin. This can be calculated by using the speed of sound. Distance = Duration/58.2.

digitalWrite(trigPin, LOW); 
 delayMicroseconds(2); 
 digitalWrite(trigPin, HIGH);
 delayMicroseconds(10); 
 
 digitalWrite(trigPin, LOW);
 duration = pulseIn(echoPin, HIGH);
 
 //Calculate distance based on speed of sound
 distance = duration/58.2;
 lcd.clear();

If distance is out of range the program will write "out of range" to the LCD and serial monitor

Else it will calculate the distance every 150 ms and print it.

if (distance >= maximumRange || distance <= minimumRange){
 Serial.println("Out of range");
 lcd.setCursor(0,0);
 lcd.print("Out of range");
 digitalWrite(LEDPin, HIGH); 
 }
 else {
 Serial.println(distance);
 lcd.print(distance);
  lcd.setCursor(3,0);
 lcd.print("Cm");
 digitalWrite(LEDPin, LOW); 
 
 }

If the button is pushed the program will open the SD card and seek the Distance.txt file and save the current distance to the log. This can be viewed later on a PC.

The command will also turn the display Green for 2 seconds and show the saved distance.

When 2 seconds are done the program will continue its main task. Measuring distance.

if(digitalRead(pinButton))                     
    {
           File dataFile = SD.open("Distance.txt", FILE_WRITE);
           
              const int colorR = 0;
            const int colorG = 255;
            const int colorB = 0;
    if (dataFile) {
    dataFile.println(distance);
    dataFile.close();  
    lcd.setCursor(0,1);
    lcd.print("Saved to SD card."); 
   
    Serial.println("saved to SD card.");
    lcd.setRGB(colorR, colorG, colorB);
    
      
   delay(2000); 
   
   const int colorR = 255;
            const int colorG = 255;
            const int colorB = 255;
            
             lcd.setRGB(colorR, colorG, colorB);
   
    }
 
    
 }
 delay(150);
}