Gadjetbox

Algorithm

Algorithm

Our objective is fully automated home security system which gives a alarm if person who tried to enter the home or office without informing. Also that should not detects pets.  The most difficult thing is identifying human beings.

So we use PIR(Piroelectric Infared ) sensors to identify human beings.  Using this sensor we found a way to detect a person while he moving. It means than sensor is motion sensor.

PIR motion sensor with Fresnel lens.

But our sensor had a few problems. It response  to the environmental and power supply variations.  So we have to use another way to avoid them. Then we use IR beam set to identify there is any thing  try to get in. After PIR sensor check whether it a human being or not. After processing that situation it gives alarm if want.

Also we add very interesting additional item. If the owner is out side that is not necessary to give only a alarm. So we prepared a item to give a signal to his mobile phone. For that unit  we use old and very cheap mobile phone to do this instead of GSM module. That is because GSM modules are very expensive.

IR beams

We used PIC16f877A microcontroller  to implement this. When we implementing this there are many inputs and outputs to consider. So that is necessary to use this PIC . Also it is very common one which easy to find in local market.  We designed simple circuit using Or CAD .

There are many thing to add to this circuit to gain its quality and accuracy. I will explain about that with more details later.

Best regards…..!!