12-07-2013, 04:43 PM
AUTOMATIC ROOM LIGHT CONTROL WITH VISITOR COUNTER ABSTRACT
AUTOMATIC ROOM LIGHT.doc (Size: 33 KB / Downloads: 83)
ABSTRACT
In this competitive world and busy schedule human cannot spare time to perform his daily activities manually. The most common thing that he forgets to do is switching OFF the lights wherever they are not required. This project is a standalone automatic room light control with visitor counter. The main aim of the project is to control the lighting in a room depending upon members that is present in the room. Use of embedded technology makes this closed loop feedback control system efficient and reliable. Micro controller (AT89C51) allows dynamic and faster control. Liquid crystal display (LCD) makes the system user-friendly. AT89C51 micro controller is the heart of the circuit as it controls all the functions.
The system comprises of two IR Transmitter-Receiver pairs, one of which is located in front of the door outside the room. Initially the light is switched off in the room. Whenever a person tries to enter into the room, the receiver of first IR pair identifies the person. Then the microcontroller opens the door by rotating the stepper motor. After the person had entered into the room completely, the door will be closed automatically.
The light is switched off even if on one is present inside the room during the day time. Similarly, the light is switched on one is there inside the room or if it is night times. Thus, depending on the intensity of light and the surrounding temperature, the required action is performed by the microcontroller. LCD displays the number of persons present inside the room.
This project uses regulated 5V, 500mA power supply. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.