Help Me ! Thanks First

Hello guys , im new to this forum if anything wrong please for give me.

i want to build a system that when ever everyone touch your door it will activate swith on for alarm device for 5 minute ?

i wondering what arduino to buy and how can i do it . My english is bad plz forgive me . thanks for all .

i wondering what arduino to buy

Any Arduino will be able to read the single input and trigger the single output.

and how can i do it

First, you need to think about how to make a door(knob) something that the Arduino can read the state of. You could, I suppose, make it into a capacitive touch sensor (a google search term for you to use).

in general you need to keep your track in to a basic idea.

what would be deferent from the time that someone come near or even touch the door

examples ( light, sound, temperature ect. )

after that you can creat in input point that continuisly check this value and at a change it trigers your output pin.

a door knob made from clear plexiglass dome with lightsensors in side would be my choise.

i am preaty sure that you can find everything easy.

for your first experiment at least while Paul is right, his idea is more apropriate.


good luck with your project.