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Electronics => Electronics => Topic started by: Jdog on July 23, 2010, 09:00:31 PM

Title: Pressure Switch
Post by: Jdog on July 23, 2010, 09:00:31 PM

Hi all. I'm looking for a simple on off switch that is activated by someone stepping on it. I used to have one, it was about 2 feet long and was basically two thin strips of metal separated by Styrofoam, and when someone stepped on it, the metal made contact and conducted electricity.

I now have a project that could use something just like that, although I cannot find any online, I keep finding pressure sensors which is not what I want. Does anyone know what I am talking about, and can anyone find one online that I can purchase?

Title: Re: Pressure Switch
Post by: Gertlex on July 23, 2010, 10:25:28 PM

There's foam that conducts.  The more it's compressed, the better it conducts.  Thus it's a variable resistor, sort of.  I've used this method for a small grabber. *shrug*

Title: Re: Pressure Switch
Post by: voyager2 on July 23, 2010, 10:27:28 PM

Hi,

This is a pressure sensor:
http://www.sparkfun.com/commerce/product_info.php?products_id=9376 (http://www.sparkfun.com/commerce/product_info.php?products_id=9376)
You might be able to attach it to a switch like a transistor or MOSFET, or maybe a relay, it depends on your application.
You could use a momentary contact switch, if you can find one big enough.
What is your application?

Title: Re: Pressure Switch
Post by: waltr on July 24, 2010, 09:54:28 AM

McMaster-Carr and other industrial suppliers have pressure sensitive mats.

Title: Re: Pressure Switch
Post by: paulstreats on July 24, 2010, 11:54:02 AM

I made something similar when a was about 12.

All I did was glue kitchen foil to 2 pieces of card, put something in between to seperate them (I made a concertina spring out of more card) and you had some contacts that connected when pressure was added.

 Wire them up to a buzzer and place under a carpet. Great Fun!!!

 maybe you could make something just as simple?

 or you could make a plate that sits over a pushbutton.

Title: Re: Pressure Switch
Post by: Soeren on July 24, 2010, 08:41:10 PM

Hi,


I'd make one myself, but if you need something factory made, this comes with a 105 dB siren (at $10) (http://www.harborfreight.com/pressure-sensitive-alarm-mat-96481.html)

Title: Re: Pressure Switch
Post by: Jdog on July 26, 2010, 12:29:48 PM

Thank you everyone who responded.

I think I'm just going to build it myself. What is online is expensive for something as simple as this.

Thanks again ;D