Project tutorial
The Range-less ROBO (A Robot with No limit and Infinite Rang

The Range-less ROBO (A Robot with No limit and Infinite Rang © GPL3+

  • 0 respects

Components and supplies

About this project

In present time almost all the people are familiar with robots. Robots play a very important role in human life. Robots are a machine which reduces the human efforts in heavy works in industries, building etc. and makes life easy. We are here with our next robot that is a Range-less ROBO. Yes we call it a Range-less because the Transmitter and Receiver which operates this ROBO does have an infinite range of operation and can be operated from anywhere around this world. Now how do we have achieved that? Thinking about our Mobile Phones we know that we can call anyone who can be at anywhere around this world until there is a network existing for communication. So how if we install a mobile phone on the Robot and communicate with that Robot with another mobile phone using the calling function.We can achieve this thing by using the DTMF technology which already exist in our Mobile phone's Dial Pads. DTMF stands for Dual Tone Multiple Frequency. There are some frequencies that we use to create DTMF tone. In simple words by adding or mixing two or more frequencies generates DTMF tone. These frequencies are given below:

In given figure we can see two groups of different frequencies. When one upper and one lower frequencies mixed then a tone is created and that tone we call Dual Tone Multiple Frequency.

What is DTMF?

DTMF is a Dual Tone Multiple Frequency decoder module which has a MT8870 DTMF decoder IC which decodes DTMF tone signal to digital signal that are acceptable for arduino digitally. Here an aux wire is needed for connecting DTMF module to phone.

Block Diagram:

Remote section: This section’s main component is DTMF. Here we get a tone from our cellphone by using aux wire to DTMF Decoder IC namely MT8870 which decodes the tone into digital signal of 4bit.Control Section: Arduino UNO is used for controlling whole the process of robot. Arduino reads commands sent by DTMF Decoder and compare with define code or pattern. If commands are match arduino sends respective command to driver section.Driver section: driver section consists motor driver and two DC motors. Motor driver is used for driving motors because arduino does not supply enough voltage and current to motor. So we add a motor driver circuit to get enough voltage and current for motor. By collecting commands from arduino motor driver drive motor according to commands.

Circuit Diagram and Working Explanation:

Circuit digram for this Robot is very similar with our other robot like Android App controlled ROBO, Obstacle Avoiding ROBO etc.. Here one motor driver is connected to arduino for driving robot. Motor driver’s input pin 2, 7, 10 and 15 is connected at arduino digital pin number 6, 5, 4 and 3 respectively. Here we have used two DC motors to driver robot in which one motor is connected at output pin of motor driver 3 and 6 and another motor is connected at 11 and 14. A 9 volt Battery is also used to power the motor driver for driving motors. A DTMF decoder attached with this circuit and this decoder is plugged into a mobile using an aux wire for receiving command or DTMF Tone. DTMF decoder pin D0-D3 is directly connected with Arduino’s pin number 19, 18, 17, 16. Two 9 Volt batteries are used to power the circuit in which one is used for power the motors, connected at motor driver IC pin number 8. And another battery is connected to power the remaining circuit.

Working of DTMF Controlled Robo:

DTMF controlled robot run by some commands that are send via mobile phone. We are here using DTMF function of mobile phone. Here we have used the mobile phone to show working of project. One is user mobile phone that we will call ‘remote phone’ and second one that are connected with Robot’s circuit using aux wire. This mobile phone we will call ‘Receiver Phone’. First we make a call by using remote phone to receiver phone and then attend the call by manually or automatic answer mode. Now here is how this DTMF controlled robot is controlled by cell phone:When we presses ‘2’ by remote phone, robot start to moving forward and moving continues forward until next command comes.When we presses ‘8’ by remote phone, robot change his state and start moving in backward direction until other command comes.When we press ‘4’, Robot get turn left till next command executed.When we press ‘6’, robot turned to right.And for stopping robot we pass‘5’.

Programming Explanation:

In program first of all we have defined output pins for motors and Input pins for DTMF decoder output as in INPUT for Arduino.

And then in setup set motor pin as OUTPUT and DTMF decoder output pins as INPUT.

After that we read DTMF decoder output and then compare with defined values by using “if” statement and perform relative operation.

There are five conditions in this DTMF controlled Robot that are giving below:We write program according to above table conditions.

Now after doing all this stuffs next part is to get the live footage from the Robot in our Laptops/PC.For that we need to install an App Airdroid in the Phone which we are going to put on the Robot. Now you just need to sign up with your email Id in that app and turn on the Internet connection in the phone, after that place that phone on the Robot.

Now in your Laptop go to here sign in with the same account through which you have sign up on the Phone.After signing in the Android App gets connected with the Laptop and by pressing the icon of camers in your laptop screen you can get the live footage from the phone which is placed on the Robot.

Note: Your phone and Laptop both should have an internet connection for this. Click below to watch the full Video tutorial on it:


Untitled fileArduino
#define m11 3
#define m12 4
#define m21 5
#define m22 6
#define D0 19
#define D1 18
#define D2 17
#define D3 16
void forward()
   digitalWrite(m11, HIGH);
   digitalWrite(m12, LOW);
   digitalWrite(m21, HIGH);
   digitalWrite(m22, LOW);
void backward()
   digitalWrite(m11, LOW);
   digitalWrite(m12, HIGH);
   digitalWrite(m21, LOW);
   digitalWrite(m22, HIGH); 
void left()
   digitalWrite(m11, HIGH);
   digitalWrite(m12, LOW);
   digitalWrite(m21, LOW);
   digitalWrite(m22, LOW);
void right()
   digitalWrite(m11, LOW);
   digitalWrite(m12, LOW);
   digitalWrite(m21, HIGH);
   digitalWrite(m22, LOW);
void Stop()
   digitalWrite(m11, LOW);
   digitalWrite(m12, LOW);
   digitalWrite(m21, LOW);
   digitalWrite(m22, LOW);
void setup() 
  pinMode(D0, INPUT);
  pinMode(D1, INPUT);
  pinMode(D2, INPUT);
  pinMode(D3, INPUT);
  pinMode(m11, OUTPUT);
  pinMode(m12, OUTPUT);
  pinMode(m21, OUTPUT);
  pinMode(m22, OUTPUT);
void loop() 
  int temp1=digitalRead(D0);
  int temp2=digitalRead(D1);
  int temp3=digitalRead(D2);
  int temp4=digitalRead(D3);
  if(temp1==0 && temp2==1 && temp3==0 && temp4==0)
  else if(temp1==0 && temp2==0 && temp3==1 && temp4==0)
  else if(temp1==0 && temp2==1 && temp3==1 && temp4==0)
  else if(temp1==0 && temp2==0 && temp3==0 && temp4==1)
   else if(temp1==1 && temp2==0 && temp3==1 && temp4==0)


Circuit diagram
Screenshot (7) m5padyjfiv


Similar projects you might like

Amazing 6WD Off-Road Robot | Arduino RC Robot

Project tutorial by Jithin Sanal

  • 48 respects

Make a Wi-Fi Controlled Simple Robot Using Arduino

Project tutorial by rajitha_kumara

  • 1 comment
  • 7 respects

4-Wheel Robot Made With Arduino Controlled Using Dabble

Project tutorial by STEMpedia

  • 24 respects

WiFi Robot

Project tutorial by Team Kartik

  • 1 comment
  • 12 respects

Arduino Bluetooth Robot for Android Device

Project showcase by aip06

  • 16 respects

MeArm Robot Arm - Your Robot - V1.0

Project tutorial by Benjamin Gray

  • 41 respects
Add projectSign up / Login