Touch Sliders With A Softpot + Arduino

Discussions area for bildr's blog posts.
From: http://bildr.org/2012/11/touch-sliders- ... t-arduino/

You all know the potentiometer, you turn it, and you can read on your arduino where it was turned to. Well 3M makes a product called the softpot that is a linear touch potentiometer. So instead of turning a knob, you touch it.

The really nice thing about these is that they are great for prototypes because you can tell where someone touched it. So if you place a piece of paper with some printed buttons over it, you can mock up surface touch ...
ameyer
Founder
 
Posts: 3264
Joined: Thu Jan 21, 2010 11:59 pm
Location: The Bay Area

Wouldn't you avoid the mentioned issue with the insertion of a simple resistor in the circuit ?
amundsen
 
Posts: 1
Joined: Sun Sep 29, 2013 1:53 pm

Kinda. You can add a resistor if you want. And I tried that, but you end up killing your resolution.

amundsen wrote:Wouldn't you avoid the mentioned issue with the insertion of a simple resistor in the circuit ?
ameyer
Founder
 
Posts: 3264
Joined: Thu Jan 21, 2010 11:59 pm
Location: The Bay Area

The issue with touching the top and bottom at the same time is that you short the 5 volt to ground, thus high current and then burn out.
RobotHacker
 
Posts: 1
Joined: Tue Jun 15, 2010 2:08 am

I hooked up a softpot linear touch slider to use as a midi controller and the issue I had was that when it wasn't touched at all, it sent signals that varied by +/- 10 or so, so in my arduino code, the part that says if the old value is not equal to the new value didn't work because the value fluctuated so much it just sent a signal endlessly. If I held it down with my finger it would work, but as soon as I let go it went bananas.
allowishus
 
Posts: 1
Joined: Sun May 15, 2016 8:00 pm

You could put a low-pass filter of sorts on it. Only change if the value is > 10. This would obviously reduce the resolution.

The analog pins can be heavily influenced by the pins next to them. Try connecting A1 to either ground or 5V through a 1K resistor. This will stabilize the pin next to it and may help you out.


allowishus wrote:I hooked up a softpot linear touch slider to use as a midi controller and the issue I had was that when it wasn't touched at all, it sent signals that varied by +/- 10 or so, so in my arduino code, the part that says if the old value is not equal to the new value didn't work because the value fluctuated so much it just sent a signal endlessly. If I held it down with my finger it would work, but as soon as I let go it went bananas.
ameyer
Founder
 
Posts: 3264
Joined: Thu Jan 21, 2010 11:59 pm
Location: The Bay Area


Return to Blog Posts

Who is online

Users browsing this forum: No registered users and 1 guest

cron