Control Your Robot Using Cellphone

THIS ENTIRE TUTORIAL IS ALSO AVAILABLE ON MY WEBSITE
Hello World in this post I will be showing you how to control robot using cellphone .Controlling a robot using cellphone is not that complicated as your thinking it is very simple The features of this robot are

It have overcome the drawback of limited range and limited control. of the bot (Controlling range as large as the coverage area of the service provider)No interface with other controllers This robot can be made in two methods
1. Without using Micro controllers hence no coding required
2. Using Micro controllers (Atmega/ Arduino) which requires coding In this post I will be making the bot using the 1st method( Without Micro controllers).If you want to make in other method please like our Facebook page for the updates

Step 1: VIDEO OF THE ROBOT

NOTE : This was a trial video taken, after the completions of the robot I have changed the appearance of the robot I have arranged all the wire and parts properly .so don’t be confused by seeing the wire and extra things in the video :)

Step 2:

Step 3: Thing You Need

Step 4: Build the Circuit

Make the circuit as per the given schematics,The circuit is divided into 4 parts

• Power supply
• CM8870 DTMF Decoder IC connection
• L293D Motor Driver IC connection
• 3.5mm Jack Connection

Step 5: Power Supply

I am using 12v geared motor for my robot so I need 12 power supply for it but the two IC in the circuit can have only 5v supply ,so to regulate the voltage I have used 7805 IC ,Which take Input current 12V and regulates it gives an output of 5V for the IC

• Solder the 7805 (Voltage Regulator), to the perfboard and place one 10 µF capacitor in INPUT & GND connection of IC 7805 and one more 10µF capacitor in GND & OUTPUT of 7805.
• Take the positive supply from the battery and connect it to INPUT of IC 7805, and also connect its negative supply to GND of 7805 and you will get 5V supply from the OUTPUT pin 3. To verifying the power flow, connect an LED to output pin via a 1K resistor

Step 6: CM8870 DTMF Decoder IC Circuit

1. Solder the DTMF decoder IC on the perf board and connect two leg of 3.57Mhz crystal to Pin 7 and 8.
2. Solder a 100K resistor from Pin 3 to Pin 2 ,Take another 100K resistor and connect one end of it to Pin 3 and end to a 0.1uf Ceramic capacitor ,Leave the connection of other end of the ceramic capacitor. I will discuss it in later step (3.5mm Jack Connection).
3. Solder another 0.1uf Ceramic capacitor between the PIN 17 and 18.
4. Solder a 330K resistor to PIN 17 from Pin 16.
5. Join Pin 1 and Pin 4 together.
6. Join Pin 5, Pin 6 and together and connect it to GND.
7. Join Pin 10 and Pin 18 together and connect it OUTPUT pin of 7805 (5v) .
8. The Pins 11 ,12 , 13, 14 are the output pins of the DTMF decoder which are to be connected to the Pins 15 , 10 , 7 , 2 of the Motor driver IC L293D respectively

Step 7: L293D Motor Driver IC Connection

1. Provide 5v supply to Pins 1 , 9 and 16 of L293D.
2. The Pin 8 provide the voltage for the Motors so connected it INPUT of 7805 or you can provide an external power supply for the motors by providing external power supply to the Pin 8.
3. The Pins 4 , 5 , 12 , 13 are to connected to GND.
4. Connect terminals of one motors to Pin 3 (Output 1) and Pin 6 (Output 2) ,and terminals of other motor to Pin 11 and 14

Step 8: 3.5mm Jack Connection

There are three different layers for the 3.5mm jack say Tip,Ring,Sleeve The tip and ring is to connected to the GND .In the dtmf IC connection circuit part I have left a connection of a 0.1uf ceramic capacitor which is to be connected to the sleeve check the below pictures for more clarifications

Step 9: Working of the Robot

After complete construction ,connect 3.5mm jack to a mobile phone and turn on the auto answer mode in the call settings and enable keypad tones in the cell phone that you use to make calls. and connect 12 power supply to the circuit.Now the robot is ready for controlling through the mobile After the jack be connected to the mobile make a call to the connected the mobile on the robot Use the above table for the controls of the robot

Please feel free to ask any doubt I will try my level best in helping :)