I am making a turnstile in sixth year could some ppl plz help what componets I need in making this as I’m very unsure
Ianmansfield14:
I am making a turnstile in sixth year could some ppl plz help what componets I need in making this as I’m very unsure
A turnstile is used in a fence line around a pasture to allow people in and out, but keep the livestock inside the fence. Perhaps you should explain your project a bit more and how an Arduino fits into the project.
Paul
I know them from the railway stations... That's where the big herds are in this place 
Sturdy frame; rotor set at a slight down angle, three poles attached to it, and a mechanism to make it snap to one of three positions and turn into only one direction. NFC card reader to unlock the thing and let you in or out of the station.
Dunno what the Arduino angle to building a turnstile would be. It's a mechanical thing first and foremost. Controlling its locking, counting passages - that could be an Arduino thing but that assumes the turnstile is in place already.
Ianmansfield14:
could some ppl plz help what componets I need in making this
Do you have to build an actual turnstile, like this?
Is the objective of the project primarily mechanical or electronics or programming or logic or what?
I made a tiny mock up of one a few years ago*. It was a boom actually, easier to build, with the boom made of Mecanno on a hinge. At the open end (ie not the hinge) the end was held down when locked by an electro magnet. Release of the turnstile was just (iirc) a button press as a place holder for swiping a card, dropping in a coin or whatever; that let go of the electromagnet.
The open end of the boom also rested in the "U" of an infrared sensor so it could sense it was open or closed.
So the idea was if you opened the boom when it was locked (not that strong a magnet) which would mimic someone trying to get in without paying, it would know it was locked-but-open and sound an alarm.
Turnstile-as-state-machine is one of the more popular ways of explaining state machins, it seems. It will be worthwhile to read this. The Wikipedia article where the diagram below comes from, may be useful.
You start locked from the black dot. If you push, it stays locked (but could sound an alarm if it's actually forced open). If you drop in a coin, it goes to unlocked. If you drop in another coin, it stays unlocked but you lose the donation. If you push, it turns and goes back to locked.
*edit: just found the cringe-worthy code from August 2014. I guess making it less-cringe-worthy is this weekend's task. Beats doing the Mrs' bidding in the veggie garden.