im doing a project to count the number of persons entering orleaving such that the counter must display people inside the room.also the sensor must detect whether the person is entering or leaving and it should not interpret hand movement as person entering the room.
PLZ HELP ME ABOUT WHICH SENSON AND CONFIGURATION I MUST USE
You may use a photoelectric cell to do this...Or if the room has a door, then a person entering or leaving may be recognised by the direction of moving the door...
You may use a photoelectric cell to do this...Or if the room has a door, then a person entering or leaving may be recognised by the direction of moving the door...
This assumes the door opens both ways...Then the problem is that if the door opens both ways some people will push to open and others will pull to open so I don't think this will quite work the count won't be accurate.
The solution would be two doors only opening in one direction but apart from the kitchen staff doors in a restaurant how many other situations have such a setup.
I wouldn't say the only way. If you use 3 pairs of these sensors evenly distributed across the height of the doorway, that completely eliminates the chance of a hand movement tricking the system. Unless the OP is expecting people to try to deliberately deceive the system (for example by two people entering at once), turnstiles should not be necessary.
I believe he's aware of that; he's suggesting that you could install turnstiles.
Brownout, the other problem is that turnstiles do not usually work in both directions, and difficulties especially occur when there's only room for a single turnstile for both directions.
Why sould two people entering the room at once be a deliberate attempt to fool the system? People move in ways that are most condusive to their own needs. The possibility of multiple people entering/leaving the room is always there. There is no system that can reliably account for that. Secure buildings require each person entering or leaving to use a magnetic badge before passing through. But even that isn't 100% reliable, as one person can 'taligate' on another. Only by controlling how people pass through can you be sure you have an accurate accounting.
You'll have to construct your own. It can be primative and work in two directions ( entering/leaving ) Use a simple rotary switch or encoder for the signal.