Published February 17, 2023

Bluetooth Mobile Robot Omniwheels

Omniwheels mobile robot with Bluetooth as a medium for receiving commands from a smartphone to move

IntermediateShowcase (no instructions)8 hours162

Things used in this project

Hardware components

Arduino Mega 2560

Rechargeable Battery, 24 V

Maxim Integrated MAX17501 60V, 500mA, Ultra-Small, High-Efficiency, Synchronous Step-Down DC-DC Converter

SparkFun Dual H-Bridge motor drivers L298

HC-05 Bluetooth Module

Software apps and online services

Arduino IDE

MIT App Inventor 2

Story

Naturally, discussing robots is quite interesting; this technology is genuinely unique and is adored by a wide range of people, from young children to adults. These days, it's easy to find robotics classes that instruct students on the fundamentals of robotics as well as how to build and program them. Researchers build or create a wide variety of robots.

The unique wheel design known as the "Omni wheel" incorporates many wheels into one central hub. There is a significant core wheel, and there are numerous smaller wheels along the edges with axes that are parallel to the core wheel axis (Wikipedia 2011).

Omni Wheel Robot is a portable robot with four unique wheels that can move and maneuver without turning the robot's body. The robot's wheels are what allow it to accomplish this. The wheels are designed in a circular shape like regular wheels, but they have extra sub-wheels on the outside, allowing the mechanical system to allow the robot to maneuver without having to change the position of the robot's body. The robot can freely move around by using the wheels, which have a mechanical shape that is slightly different from other wheels generally.

https://tripleinnovation.com.au/case-studies/whats-in-a-wheel/

As shown in the following image,

four omni wheels are placed with a 45-degree intersection angle and 90-degree perpendicularity to the mobile platform coordinate system. The speed of the four omni wheels is thus

where vi, ωi and ̨i are the velocity, angular speed and the anglebetween the ith wheel axis and Xm direction of platform, respec-tively. r and R are the omni wheel radius and the radius of platform,respectively.

Code

Mobile.ino

unsigned int kana1= 2;
unsigned int kana2= 3;
unsigned int kanb1= 4;
unsigned int kanb2= 5;
unsigned int kira1= 6;
unsigned int kira2= 7;
unsigned int kirb1= 8;
unsigned int kirb2= 9;
int pwm=100;
void setup() 
{
 pinMode(kana1, OUTPUT);
 pinMode(kana2, OUTPUT);
 pinMode(kanb1, OUTPUT);
 pinMode(kanb2, OUTPUT);
 pinMode(kira1, OUTPUT);
 pinMode(kira2, OUTPUT);
 pinMode(kirb1, OUTPUT);
 pinMode(kirb2, OUTPUT);
 Serial1.begin(9600);
 Serial.begin(9600);
}

void loop() 
{
 if(Serial1.available())
 {
  char data= Serial1.read();
  if(data =='a'){pwm=pwm+10; Serial.println(pwm);}
  if(data =='b'){pwm=pwm-10; Serial.println(pwm);}
  if(data =='c'){maju(); delay(100); Serial.println("maju");}
  if(data =='d'){mundur(); delay(100); Serial.println("mundur");}
  if(data =='e'){kanan(); delay(100); Serial.println("kanan");}
  if(data =='f'){kiri(); delay(100); Serial.println("kiri");}
  if(data =='g'){putar1(); delay(50);Serial.println("putar1");}
  if(data =='h'){putar2(); delay(50);Serial.println("putar2");}
  
 }
 else{berhenti();Serial.println("berhenti");}
}

void maju()
{
 analogWrite(kana1, pwm);
 analogWrite(kana2, 0);
 analogWrite(kanb1, pwm);
 analogWrite(kanb2, 0);
 analogWrite(kira1, 0);
 analogWrite(kira2, pwm);
 analogWrite(kirb1, 0);
 analogWrite(kirb2, pwm); 
}

void mundur()
{
 analogWrite(kana1, 0);
 analogWrite(kana2, pwm);
 analogWrite(kanb1, 0);
 analogWrite(kanb2, pwm);
 analogWrite(kira1, pwm);
 analogWrite(kira2, 0);
 analogWrite(kirb1, pwm);
 analogWrite(kirb2, 0);
}

void kanan()
{
 analogWrite(kana1, pwm);
 analogWrite(kana2, 0);
 analogWrite(kanb1, 0);
 analogWrite(kanb2, pwm);
 analogWrite(kira1, 0);
 analogWrite(kira2, pwm);
 analogWrite(kirb1, pwm);
 analogWrite(kirb2, 0);
}

void kiri()
{
 analogWrite(kana1, 0);
 analogWrite(kana2, pwm);
 analogWrite(kanb1, pwm);
 analogWrite(kanb2, 0);
 analogWrite(kira1, pwm);
 analogWrite(kira2, 0);
 analogWrite(kirb1, 0);
 analogWrite(kirb2, pwm);
}

void berhenti()
{
 analogWrite(kana1, 0);
 analogWrite(kana2, 0);
 analogWrite(kanb1, 0);
 analogWrite(kanb2, 0);
 analogWrite(kira1, 0);
 analogWrite(kira2, 0);
 analogWrite(kirb1, 0);
 analogWrite(kirb2, 0);
}

void putar1()
{
 analogWrite(kana1, pwm);
 analogWrite(kana2, 0);
 analogWrite(kanb1, pwm);
 analogWrite(kanb2, 0);
 analogWrite(kira1, pwm);
 analogWrite(kira2, 0);
 analogWrite(kirb1, pwm);
 analogWrite(kirb2, 0);
}

void putar2()
{
 analogWrite(kana1, 0);
 analogWrite(kana2, pwm);
 analogWrite(kanb1, 0);
 analogWrite(kanb2, pwm);
 analogWrite(kira1, 0);
 analogWrite(kira2, pwm);
 analogWrite(kirb1, 0);
 analogWrite(kirb2, pwm);
}