This document describes a bidirectional visitor counter project created by students to count the number of people entering and exiting a room. The system uses infrared sensors and a microcontroller to detect movements and update the count on a 7-segment display. While basic, it provides an educational experience and could help automate energy usage. Improvements are needed to differentiate individuals from other objects and handle multiple simultaneous entries. Potential applications include events, meetings, and homes.

1. PREPARED AND PRESENTED BY:
ZAKIR GULZAR(1235223)
ANIKET DWIVEDI(1235214)
SAHIL CHALANA(1344428)
WASEEM HASSAN(1235222)
ROUF UL RASOOL(1254306)
BIDIRECTIONAL VISITOR COUNTER
ARYANS COLLEGE OF ENGINEERIN
G

2. INTRODUCTION TO PROJECT
This project titled “Microcontroller based Bidirectional Visito
r counter” is designed and presented in order to count the v
isitors of an auditorium, hall, room, offices, malls, sports venu
e, etc.
The system counts both the entering and exiting visitor of the
auditorium or hall or other place, where it is placed. Dependi
ng upon the interrupt from the IR sensors, the system identifi
es the entry and exit of the visitor.
On the successful implementation of the system, it displays t
he number of visitor present in the room. This system can be
economically implemented in all the places where the visitors
have to be counted and controlled.

3. WHY THIS?
 This system can be used as an automated switch to inc
rease energy efficiency. The system can be used at the
entrance of a room to control the lights and other ap
pliances.
 E.g: when the number of people in the room is zer
o,the circuit can automatically switch off the power
and thus preventing the energy wastage.
 Moreover, we wanted to learn about electronics and c
ircuits. So we took up this project .

4. COMPONENTS
 Resistors
 Potentiometer
 Capacitors(Ceramic and electrolytic)
 Microcontroller(8052)
 Op-amp(Comparator)
 Regulator(LT543)
 Diodes(1N007)
 Phototransistor(LPT80A)
 Seven segment displays
 Transformer(12/500mA at 220V AC)
 LEDs and IR LEDs
 Reset switch
 Crystal Oscillator (12Mhz)

5. BLOCK DIAGRAM

6. CIRCUIT DIAGRAM

7. OPERATION
 When the system is powered, the compiler initially init
ializes the stack pointer and all other variables.
 It then scans the input ports (PortP1.0 first). In the me
antime, when there is no interruption between the IR
LED and the phototransistor of the first sensor pair, th
e output of the phototransistor is always at low voltag
e.
 In other words port P1.0 is at logic low level

8.  Now when a transition takes place, i.e a logic high leve
l is received at port P1.0, the compiler sees this as an i
nterruption to sense the passage of a person or an obj
ect between the IR LED and the phototransistor.
 As per the program, the count value is increased and t
his value is displayed on the 2-Digit Counter.
 Now the compiler starts scanning the other input
port P1.1.
 Similar to the first sensor pair, for this sensor pair also
the phototransistor conducts in absence of any interru
ption and P1.1 is at logic low level

9.  In case of an interruption, the port P1.1 goes high and
this interruption is perceived by decreasing the value
of count.
 The program ensures that the scanning of both the po
rt pins is done at certain delays so as to avoid confusio
n of reading.
 For instance port P1.0 is scanned for two or three inte
rruptions so as to ensure the count value is above
1 or 2.

10.  Now the compiler starts scanning the other input pin-
P1.1.
 Similar to the first sensor pair, for this sensor pair also
the phototransistor conducts in absence of any interru
ption and P1.1 is at logic low level.
 In case of an interruption, the pin P1.1 goes high and
this interruption is perceived by decreasing the value
of count.

11. PROBLEMS AND IMPROVEME
NTS
 This is a very basic circuit and has many shortcoming
s.
 For example, this system will not differentiate betwee
n a person and any other obstacle interrupting the sen
sors.
 Also this circuit is good enough for only one person e
ntering at a time.
 Also, this is a short range system. For long range, we
use lasers.
 For overcoming these and many other problems with t
his system, further improvements are being done. Ca
meras and processing is now being used to differentia
te between different interruptions.

12. APPLICATIONS
 This circuit can be used domestically to get an indicati
on of number of persons entering a party
 It can be used at official meetings.
 It can be used at homes and other places to keep a ch
eck on the number of persons entering a secured plac
e.
 It can also be used as home automation system to ens
ure energy saving by switching on the loads and fans o
nly when needed.

13. CONCLUSION
 We just took up this project as we were interested
in electronics and wanted to learn about it. Throu
gh this project, we learnt a lot about the functionin
g and use of different electronic components and
their applications in real life. We were able to corr
elate what we studied in our course to real life.
 Also this is very simple and effective idea which c
an be used in many places like hostel and hotel r
ooms to save energy.