An adaptive traffic control system was developed where the traffic load is continuously measured by sensors connected to a microcontroller-based system which also performs all intersection control functions. Intersection controllers of an area are interconnected with a communication network through which traffic load and synchronization information is exchanged.
As a result, the duration and relative phases of each traffic light cycle change dynamically. For the basic function of the system only the intersection controllers are required.
INTRODUCTION
Implementation
Microcontroller based traffic control system is an application specific project, which is used to control the traffic. An embedded system is developed which consists of a microcontroller, IR transmitter and receiver, LED’s
This project is implemented by placing IR transmitters, receivers and led’s at the 4 way junction, the four paths are represented as R1,R2,R3,R4
BLOCK DIAGRAM DESCRIIPTION
The block diagram consists of microcontroller interfaced to regulated power supply, led and IR receiver and IR transmitter which consists of an IR sensor
The IR sensors and leds are connected to any of the port pins of microcontroller,regulated power supply is connected to the Vcc pin of microcontroller which uses an voltage regulator to get 5 v of power supply. The transmit pin of IR receiver is connected to the receive pin of microcontroller
This embedded system is placed at the 4 way junction which controls the traffic electronically The system uses a compact circuitry build around flash version of AT89S52 Microcontroller with a non-volatile memory. Programs will be developed in EMBEDDED C language. FLASH MAGIC is used for loading of programs into microcontroller.
IR TRANSMITTER and receiver
The purpose of the transmitter is to transform the information we want to send into a signal that can be propagated by the channel. In the case of our wired copper channel, this means we want the information to be transformed into a modulated voltage level, something like the pulse train. For a wireless channel, however, the transmitter needs to encode the information onto an EM wave that can be easily propagated.
Description
The TSOP17.. – series are miniaturized receivers for infrared remote control systems. PIN diode and preamplifier are assembled on lead frame, the epoxy package is designed as IR filter.
The demodulated output signal can directly be decoded by a microprocessor. TSOP17.. is the standard IR remote control receiver series, supporting all major transmission codes.
EMBEDDED SYSTEM
An embedded system is a special-purpose computer system designed to perform one or a few dedicated functions[1], sometimes with real-time computing constraints. It is usually embedded as part of a complete device including hardware and mechanical parts. In contrast, a general-purpose computer, such as a personal computer, can do many different tasks depending on programming. Embedded systems have become very important today as they control many of the common devices we use.
Since the embedded system is dedicated to specific tasks, design engineers can optimize it, reducing the size and cost of the product, or increasing the reliability and performance. Some embedded systems are mass-produced, benefiting from economies of scale.
Physically, embedded systems range from portable devices such as digital watches and MP3 players, to large stationary installations like traffic lights, factory controllers, or the systems controlling nuclear power plants. Complexity varies from low, with a single microcontroller chip, to very high with multiple units, peripherals and networks mounted inside a large chassis or enclosure.