Study of PLC and Its Application In A Smart Traffic Control System

Abstract

PLC or Programmable logic controller was used to control a mechantronics system using specific functions.Basic PLC functions such as timing,sequencing,controlling and relaying were implemented.The basic programming logic and ladder programming was studied and implemented.The intelligent or “Smart Traffic Control” is one which would be able to calculate the vehicle density in a lane at a 4-way crossing and then decide the priority automatically using a program burned in microcontroller. In practical situations sensors are used to detect presence of vehicles in a lane and calculate the density and sends an interrupt signal to the control unit .In PLC the status of the sensors are checked and certain logical operations are performed to decide which lane is to be serviced first.Under low density condition it would operate sequentially.Ladder diagram was developed for the implementation of the same in PLC.