Automatic door
Automatic door:
if any one enter from door then door will be automatically open .after cross the door the door will automatically closed.
Theory :
In this case we use LDR.When a light ray fell on LDR then resistance of LDR decrease. System work properly we use laser.When laser fell on LDR resistance will decrease. Then any think will come in between laser and LDR . Resistance will increase .This method we use outside of door and control motor 1 for opening the door and inside we also use the this system control motor 2 for closing the door.motor 1 and motor 2 are show in Fugger.
We use transistor because the minimum resistance of LDR is in simple laser light 1700 ohm then at this resistance we can't work properly then we use transistor.
in this case if we not use transistor then we can't run motor then we use transistor and amplifier the signal .
required apparatus:
1.LDR
2.diode -4001(2)
3.transistor -2n2222(2)
4.motor(12volt dc Gare)
5.preset-50k or(potentiometer)
6.ply wood (for wall and door)
8.paint(red door color)
9.Two wheel(for moving door)
10.relay(6 volt)
Top view:
Arrange as show in Fugger and put motor ,LDR and laser properly
How to make this :Make two times this circuit and attach by motor.
case 1. any one enter from door then 1st laser will cut now door automatically open.(sift from one Fugger to two)
case 2:
when he cross the door second laser will cut then door will automatically close.(sift from 2nd to third )
suraj kumar
nit agartala
