I've tried a couple different thumbstick potentiometers from sparkfun.com and adafruit.com and I'm having difficulty finding one that doesn't have a deadzone when the joystick is centered. I get why this is important when dealing with video-games - you don't want your character running off on it's own. But I'm working with a couple of servos and I'd like to have the servo move in direct proportion to the thumbstick, without it stopping along the way. I hope that makes sense. Here's a link to one of the ones I purchased:
But I'm working with a couple of servos and I'd like to have the servo move in direct proportion to the thumbstick, without it stopping along the way. I hope that makes sense. Here's a link to one of the ones I purchased:
I think you are going to have a hard time finding one that works like that because the problem you are describing is caused by more than one factor. The resolution of the pot is very low. Measure the pot resistance . If you want to see a servo behave the way you are describing try using the joystick on an RC radio transmitter with the receivers hooked up to a radio reciever. You will see you have complete control and they track the position of your thumb. That's absolutely necessary when flying aircraft or helicopters.
Yeah, I think RC joysticks are the way to go. So I took apart an RC drone controller that I had to see what was being used. It looked identical to the ones I had bought from sparkfun and adafruit but it didn't have the deadzone inherent in those. Here's a picture of it.
So I know they're out there. And I'm okay with it not being super-precise. I just want the servo to move fairly smoothly to match the motion of the joystick - without it pausing anytime I'm nearing the neutral position. In any event, the only markings I could see on the drone controller was "CF" stamped on the metal. But I can't find a manufacturer of thumbstick pots with those initials. I've also looked at data sheets on several of these types of sensors on digikey but I'm not finding any info on whether there's a deadzone or not. Thanks for your help - if anyone else knows where I can get something like this, I'd really appreciate it.
Hmm... I may have found what I'm looking for. I noticed on some of the data sheets for joystick pots, you can choose between "center tap" or not. And doing some further digging online, a center tap may be what's causing the deadzone. I'm completely new to electronics so I may be completely wrong but I figured I'd post my thoughts in case someone can either confirm this or correct me.
Sure thing. Here's a link to the data sheet for the 252 series from CTS. If you go the bottom of the pdf, under "Ordering Information", you'll see what the part number can tell you. Specifically, I was looking at the 2nd to last digit for whether or not it had a center tap (N for no tap, T for 4 degree center tap). Again, I could be completely wrong on whether or not that has anything to do with a deadzone so I'm hoping someone with some mad datasheet reading skills could chime in.
