• The main intention is to design a system where in the number of persons
entering or leaving a room is kept track of and diaplayed on a screen.
• When a person enters the room, count would be increased, whereas on
leaving, the count would decrease.
• IR sensing mechanism is used to sense the presences of visitors and the
whole counting operation is done by a µc.
• With the help of this system we will be checking the number of people
entering and leaving from a particular confined area.
• This will help maintain the crowd during this pandemic, and in general as
• If the visitor count crosses a certain number (defined by the system owner
or a by a default value), the display will show a message to try and alerat
the owner, so that necessary actions can be taken by him.
• The circuit works on the principle of IR sensing. Infrared or simply IR
sensors are devices that work with Infrared Light Sources and a Photo
Detector like a photo Diode or a Photo Transistor that act as a
Transmitter and Recevier respectively.
• In this Project, we have used an IR LED as the IR Transmitter and a Photo
Diode as the IR Receiver. Two sets of IR Sensors consisting of an IR LED
and Photo Diode are placed at two ends of the entrance of a room.
6. Methodology (contd..)
• Output from each sensor is fed to the µC. In normal operation, IR light
from the LED would fall on the Photo Diode as it is a Reflective type IR
Sensor. The outut from the sensor would be a logic LOW signal in this case.
• In case of any interruption (due to any person crossing the path), the
Photo Diode would stop receiving the IR Light. As a result, the output from
the sensor would be a logic HIGH signal.
• The transition from low to high, for each sensor pair is detected by the µC
and accordingly the count would be increased or decreased.
9. Hardware and Software
• AT89C51 (8051 based µC)
• 8051 Programmer
• Push Button
• 10 µF Electrolytic capacitor
• 2 x 10KΩ Resistor (1/4 watt)
• 11.0592 MHz Crystal
• 16 x 2 LCD Display
• 10KΩ Potentiometer
• 2 x IR Sensors (Reflective Type)
• Connecting Wires & Power Supply
• Keil µ Vision Software (for codes)
• Proteus (for circuit making)
10. Advantages and DisadvantagE
• Provide information to management on the volume and flow of people
throughout a location. Human-based data collection comes at great
• No. ssd and ic we can add for higher counting.
• Low-cost microprocessor based visitor counter is easy to build.
• It can't work as both Entry and Exit. Disadvantage
• Can be used in Shops and other confined public areas to count the
number of people entering and leaving a building.
• This will help control the crowd inside to ensure practical social distancing
during the pandemic.
• We just took up this project as we were interested in electronics and
wanted to learn about it. Through this project, we learnt a lot about the
functioning and use of different electronic components and their
applications in real life. we were able to correlate what is studied in our
course to real life.