Published February 4, 2020 © LGPL

Pluto Bluetooth RC Car

Pluto is a 2WD Bluetooth car on which is placed a self-balancing plane.

BeginnerFull instructions provided2 hours5,850

Things used in this project

Hardware components

Arduino UNO

DFRobot 6 DOF Sensor - MPU6050

DC Motor, 12 V

L298N Driver Motor

Breadboard (generic)

Jumper wires (generic)

Male/Female Jumper Wires

SG90 Micro-servo motor

9V battery (generic)

to power the Arduino board

AA Batteries

To power the DC motor

Battery Holder, AA x 8

Software apps and online services

Arduino IDE

Ultimaker Cura

SolidWorks 2019/20

Hand tools and fabrication machines

3D Printer (generic)

Hot glue gun (generic)

Soldering Station, 110 V

Story

Pluto is a project about a particular Bluetooth machine.

This car can be controlled by a mobile phone, connecting the car on the Bluetooth we have used the app Arduino Bluetooth Controller which can be found on the Play Store.

On it are installed a self-balancing platform composed of two floors connected to two servo motors, which keep the horizontal plane, by means of an accelerometer, which calculates the angle and sends the same values to the servomotors, but opposite.

We decided to do this project for two reasons: 1. have a child play; 2. to be able to bring a glass to a person without emptying it if there are ramps.

The operation is simple: sending a Bluetooth signal from the phone the arduino card detects it and makes the machine move left, right, forward, backward or stand still based on what we want it to do to it.

For the self-balancing plane it stabilizes independently thanks to the two servo motors, the accelerometer and the gyroscope (MPU6050).

Schematics

Code

Pluto car code

char t;
#include <Wire.h>          //include the required libraries
#include <MPU6050.h>       //include MPU6050 libraries
#include <Servo.h>
MPU6050 sensor ;          //create an instance of the MPU6050 named sensor
Servo sg90y;
Servo sg90x;
int servo_pinX = 2;
int servo_pinY = 3;
int motor1A = 4;
int motor1B = 5;
int motor2A = 6;
int motor2B = 7;

int16_t ax, ay, az ;      //declare 6 16 bit integer variables
int16_t gx, gy, gz ;      //declare 6 16 bit integer variables

void setup() {
  pinMode(servo_pinX, OUTPUT);
  pinMode(servo_pinY, OUTPUT);
  pinMode(motor1A, OUTPUT);
  pinMode(motor1B, OUTPUT);
  pinMode(motor2A, OUTPUT);
  pinMode(motor2B, OUTPUT);
  pinMode(A5, INPUT);
  pinMode(A4, INPUT);
  sg90x.attach ( servo_pinX );
  sg90y.attach ( servo_pinY );
  Wire.begin ( );                  //begins the trasmission with MPU6050
  sensor.initialize ( );           //initialise the sensor
  Serial.begin(9600);
  delay(400);
}
void forward() {
  digitalWrite(motor1A, LOW);
  digitalWrite(motor1B, HIGH);
  digitalWrite(motor2A, LOW);
  digitalWrite(motor2B, HIGH);
}

void reverse() {
  digitalWrite(motor1A, HIGH);
  digitalWrite(motor1B, LOW);
  digitalWrite(motor2B, LOW);
  digitalWrite(motor2A, HIGH);
}
void right() {
  digitalWrite(motor1B, HIGH);
  digitalWrite(motor1A, LOW);
  digitalWrite(motor2B, LOW);
  digitalWrite(motor2A, HIGH);
}
void left() {
  digitalWrite(motor1B, LOW);
  digitalWrite(motor1A, HIGH);
  digitalWrite(motor2B, HIGH);
  digitalWrite(motor2A, LOW);
}
void nomove() {
  digitalWrite(motor1B, LOW);
  digitalWrite(motor1A, LOW);
  digitalWrite(motor2B, LOW);
  digitalWrite(motor2A, LOW);
}
void loop() {
  sensor.getMotion6 (&ax, &ay, &az, &gx, &gy, &gz);   //read 6 values into 6 variables
  ay = map (ay, -17000, 17000, 0, 180) ;              // change the range of the ay value from -17000/17000 to 0/180
  sg90y.write (ay);
  ax = map (ax, -17000, 17000, 0, 180) ;              // change the range of the ax value from -17000/17000 to 0/180
  sg90x.write (ax);
  if (Serial.available()) {

    t = Serial.read();
    Serial.println(t);                               //Read the incoming data and store it into variable t
    if (t == 'F') {
      forward();
    }
    else if (t == 'B') {
      reverse();
    }
    else if (t == 'L') {
      left();
    }
    else if (t == 'R') {
      right();
    }

    else if (t == 'S') {
      nomove();
    }
  }
}

Pluto Bluetooth RC Car