555 timer

Discussion in 'The Projects Forum' started by theanih, Oct 22, 2010.

  1. theanih

    Thread Starter New Member

    Oct 3, 2010
    i'm building a device for blind people which vibrates if it sense an object is in the way of the device. my initial plan is to connect a photosensor to a 555 ic and its output is connected to a vibrator. what kind of circuit (astable/monostable/bistable) is the most suitable for this? i was thinking on using monostable so that everytime an the photosensor sense an object the vibrator will vibrate for several seconds. but then again you guys know more than me in this kind of thing so i'm hoping for some advice etc to make my mind.
  2. Kermit2

    AAC Fanatic!

    Feb 5, 2010
    perhaps a small battery driven 'vibrator' motor would be better than an oscillator and speaker set up. then a simple transistor switch could activate the vibration mode. Google pager motor.
  3. arunsjoshi

    New Member

    Oct 22, 2010
    Instead of using a vibrator or speaker, use a ceramic buzzer, which consumes much less power and emits an audible sound. I am not sure how you are going to use a photosensor.But if you are able to take care of this part, you should use it to trigger a monostable.
    Last edited: Oct 23, 2010
  4. theanih

    Thread Starter New Member

    Oct 3, 2010
    thanks to both of you. i will try to find out about the pager motor but i may not use it at this moment as i'm just helping my friends on their project and all the components have been bought.
    so monostable it is.

    thanks again.
  5. marshallf3

    Well-Known Member

    Jul 26, 2010
    http://www.goldmine-elec.com just got in several new pager motors, they're often on sale for 0.49. Tiny enough to be used anywhere but noticeable enough to be useful.

    As much work as I put inon a ladder this week what I need is a blanket filled with them, it would be like thousands of tiny massaging fingers. :)
    theanih likes this.
  6. wayneh


    Sep 9, 2010
  7. mbohuntr

    Active Member

    Apr 6, 2009
    You need to run a chainsaw for a while to calm those nerve endings...:D