Obstacle Avoiding Robot With IR Sensors Without Microcontroller

Well this project is an older project, I made it in 2014 in the month of July or August, thought of sharing it with you guys. Its a simple obstacle avoiding robot that uses IR sensors and works without microcontroller. The IR Sensors uses opamp IC i.e. LM358N. You have to make two IR sensors and then connect it with L293D motor driver IC which is connected to motors.

Step 1: Gathering Components

Gather these components:

For IR SENSORS:

1) 1K Resistor

2) 10K Resistor

3) IR Receiver LED's

4) IR Transmitter LED's

5) LM358N OP-AMP IC

6) 10K TRIMPOT

7) 8 Pin IC Logic Chip Socket

8) 3 Pin wire connector

For Main Circuit:

9) IC 7407 Hex inverter IC

10) IC L293D Motor Driven IC

Other Parts:

11) 12V Geared Motor

12) Wheels

13) Sheet for making body

14) Motor holder (Pipe holder)

15) Castor Wheel

16) 2 Pin wire connector

17) Battery

18) Battery holder

19) Switch

20) Jumpers

21) Verroboard

22) Soldering Iron

23) Soldering Wire

Step 2: MAKING IR SENSOR MODULES

Ok so we have all the parts in gathered LETS START BUILDING...!!

First we will make IR Sensor the Circuit Diagram is given.

TESTING SENSORS:

Connect battery, 9V battery can be used doesn't matter. It won't harm IC LM358N, now move your hand towards the IR receiver the LED on pin 1 should glow when your hand is near IR Transmitter. The IR Transmitter LED should be a little tilted towards the IR Reciever LED, it should not be parallel. So that the Infrared rays transmitted from the IR Transmitter after hitting to an object should be reflected towards the Receiver and hence the LED on pin 1 glows. Notice I used two IR Transmitter LEDS across the IR Receiver LED just for accuracy.

Step 3: MAKING MAIN CIRCUIT

The circuit diagram of main circuit is given.

After building this main circuit connect it to two IR Sensor module circuits as shown in figure.

Step 4: MAKING BODY

I didn't made the body special, just used single sheet of acrylic and pasted the circuit's over it, as shown in images.

I used pipe holders to hold motors on acrylic sheet.

Step 5: ASSEMBLE

Assemble all the parts, connect the both IR Sensor Modules with the main circuit. and place it on the body of the Robot. Connect the switch. The IR Sensors should be at same LEVEL with the tires as shown in images.

You must be wondering why i used two 9v batteries. When I completed the robot I noticed that the robot was even slow on +9V battery (since I was using 12V Geared motors) so I added another +9V battery. So now I had two batteries both +9V one was new and the other was giving I think 8+ Volt. I added both so I got 9+8 above 17 volt. And now the robot was running with speed.