Introduction to laser guided appliance control:

In today’s growing technological developments there are  many available techniques for controlling appliances. In Laser Guided Appliance Control Project Report we will use laser diodes for controlling of appliance. The controlling of the appliance is possible by light intervention method. In this a automatic door opening system is designed which works on a laser. The output of this device is fed to relay which connects dc motor which opens the gate.

Circuit description and working:

A laser pointer or a laser diode can be used for the generation of laser light. The overflow currents coming to the laser are controlled by a combination of resistor and diode. A photo transistor is used which works in forward and reverse bias according to laser light intervention.  An IC(dd4538) is used around which a monostable mutivibrator is built which generates a high going pulse. The photo transistor will be in forward bias as lomg as the light falls on the transistor , if the light beam is interrupted the transistor goes to reverse bias condition.  The  ic calculates the interrupted time and then generate the signal pulse which drives the relay of the motor to open the door. A peizo electric buzzer is connected to the circuit which gives an alarm when the door opens. The laser bam has to be fixed in such a way that it falls continuously on the photo transistor.

Applications and advantages:

This type of devices can be used for designing security alarm systems. These can be used for design of home automation devices. The devices can also be designed by employing sensors, but the cost becomes high and it has some drawbacks.  The laser works effectively in giving responses but the light beam should be protected from disturbances due to external factors. 

Download Laser Guided Appliance Control Project Report.