Potentiometers

[electroken]

Originally Posted by gixxy

Could someone tell me which model your team has used, and how well they worked?

I want to know because I have heard they are much better than the gyro for measuring angle and movement, ect.

A gyro is a great device to sense rotation of the entire robot and we're using two of them for that (pitch and yaw). We're using a potentiometer for feedback of our shooting turret position and they are well suited for such a task. A few guidelines for choosing the right one are:

Use a linear taper pot unless you want deal with the logarithmic output of an audio taper pot (you don't).

Choose a pot with enough mechanical rotations for the job to avoid hitting the internal stops. Breaking the stops will often take out the wiper too. The 10-turn pot on our turret sees about 6 rotations when the turret moves stop to stop.

Choose a relatively low resistance pot to avoid interference issues from nearby PWM and other noisy signals. I would go no higher than 10k if I couldn't get a 1k unit. A 1k pot will only draw 0.005 amps from the analog bumper. You won't even notice that.

Choose a pot rated for enough mechanical cycles to last as long as you need. They aren't all the same and some have startlingly low rotational lives.

Radio Shack pots are junk. If you believe nothing else here, believe this.