Description

A ESP32 BASED BLUETOOTH MINI ROBOT

A simple mini robot that you can control with your phone. The robot can be improvised and implemented for various objectives. We here are going to speak about the making of the robot.

MATERIALS REQUIRED

ESP32

Breadboard

L293D motor controller

IR module

10 mm LED

1 k resistor

Robot Chassis

4 x AA Battery

Micro usb cable

6 x male to male and male to female cables

STEPS TO BUILD THE ROBOT CHASSIS

STEP 1 - MOUNT MOTORS TO THE BODY

Mount the motors with the help of supports , nuts , and bolts.

STEP 2 - ADDING THE FRONT WHEEL

Mount the pillars to the wheel and screw on the pillars to acrylic body

STEP 3 - ATTACHING BATTERY BOX AND SWITCH

Place the switch into the hole in the acrylic body. Screw the battery box onto the body.

STEP 4 - SOLDERING THE SWITCH

Solder the switch to the battery

STEP 5 - INSTALLING BATTERIES AND MAKING THE MOTOTR CONTROLLER INTERFACE

Follow the circuits above.

STEP 6 - CONNECT MOTOR CONTROLLER

STEP 7 - CONNECT TO ESP32

Make the final connections and your robot is ready to go

The link to the code and app

Code

MOTOR CONTROL INTERFACE

C/C++

#include "BluetoothSerial.h"

#if !defined(CONFIG_BT_ENABLED) || !defined(CONFIG_BLUEDROID_ENABLED)
#error Bluetooth is not enabled! Please run `make menuconfig` to and enable it
#endif

#if !defined(CONFIG_BT_SPP_ENABLED) 
#error Serial Bluetooth not available or not enabled. It is only available for the ESP32 chip.
#endif

BluetoothSerial SerialBT;

// Variable for storing incoming value
char Incoming_value = 0;

//L293D
//Motor A
const int motorPin1  = 26;  // Pin 14 of L293
const int motorPin2  = 25;  // Pin 10 of L293
//Motor B
const int motorPin3  = 33; // Pin  7 of L293
const int motorPin4  = 32;  // Pin  2 of L293

//This will run only one time.
void setup(){
    // for serial data transmission
    Serial.begin(115200);
    SerialBT.begin("Azhar"); //Bluetooth device name

    //Set pins as outputs
    pinMode(motorPin1, OUTPUT);
    pinMode(motorPin2, OUTPUT);
    pinMode(motorPin3, OUTPUT);
    pinMode(motorPin4, OUTPUT);

}


void loop(){
{
  if (SerialBT.available() > 0)
  {
    // Read the incoming data and store it in the variable
    Incoming_value = SerialBT.read();

    // Print value of Incoming_value in Serial monitor
    Serial.print(Incoming_value);
    Serial.print("\n");

    // Checking whether value of the variable
    if (Incoming_value == 'f')
      forward();
    else if (Incoming_value == 'b')
      backward();
    else if (Incoming_value == 'l')
      left();
    else if (Incoming_value == 'r')
      right();
     else if (Incoming_value == 's')
      stopRobot();
  }

  // Adding a delay before running the loop again
  delay(1);

}
}

void forward(){
    digitalWrite(motorPin1, HIGH);
    digitalWrite(motorPin2, LOW);
    digitalWrite(motorPin3, HIGH);
    digitalWrite(motorPin4, LOW);  
}

void backward(){
    digitalWrite(motorPin1, LOW);
    digitalWrite(motorPin2, HIGH);
    digitalWrite(motorPin3, LOW);
    digitalWrite(motorPin4, HIGH);
}

void left(){
    digitalWrite(motorPin1, HIGH);
    digitalWrite(motorPin2, LOW);
    digitalWrite(motorPin3, LOW);
    digitalWrite(motorPin4, LOW);
}

void right(){
    digitalWrite(motorPin1, LOW);
    digitalWrite(motorPin2, LOW);
    digitalWrite(motorPin3, HIGH);
    digitalWrite(motorPin4, LOW);
}

void stopRobot(){
    digitalWrite(motorPin1, LOW);
    digitalWrite(motorPin2, LOW);
    digitalWrite(motorPin3, LOW);
    digitalWrite(motorPin4, LOW);  
}

Schematic and Layout

MOTOR CONNECTION INTERFACE

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