In an effort to build my own star trek type doors, I rigged a couple of pneumatic cylinders together with a 110V, 150psi 4-way solenoid valve. I want to hook the system up to 2 3-way motion sensors (one on each side of the door) to activate the solenoid and open/close the doors. What I need help with is a switching device that can activate the solenoid and deactivate a few seconds later once the motion has stopped and the person has passed through the doors. Most of the motion activated light switches have a minimum delay of 8-11 seconds (very un-startrek) any ideas how I can treak these switches to lesson the off cycle to about 2 seconds?
I have seen a few "delay circuits" in these forums, but I am not experienced enough to know what I will need in terms of transformers since I will be working with house current (110). Any help is appreciated.
Take a look at the datasheet and application notes for the 555 timer IC. I just did a Google search for "555 timer pulse" and this was the first hit: http://www.kpsec.freeuk.com/555timer.htm
Make sure you include some provision for holding the doors open if some moron stands in the middle of them for more than a few seconds! You don't want the doors crushing anyone.
Star Trek Doors
Posted - Jun 21 2007 : 4:28:41 PM
