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Snaykbt
10-22-2008, 02:56 PM
I'm making a pan tilt camera head. I'm using a PS2 type joystick analog out to a 2X10 sabortooth controller. It works fine and you can vary the speed by carefully feathering the joystick. My problem is that it can be a bit touchy and unpredictable at times. I've heard of placing a microcontroller board in between the joystick and speed controller, but what I'd like to know how to do is how to use some kind of potentiometer to control the sensitivity of the joystick. Does anyone know how to go about doing this?

Thanks

Dave

Adrenalynn
10-22-2008, 03:23 PM
Welcome to the forum!

Yup - that'd take a microcontroller. You'd take the output from the joystick to the microcontroller, and the output from the pot to the microcontroller. You'd read the joystick position, read the pot, and then spit-out a scaled output that combines the joystick with the scalar from the pot.

ScuD
10-22-2008, 05:03 PM
I'm confused- if you're using an analog output of the joystick, can't you just wire a pot in series with the output as a voltage divider and use that as a scale?

Granted, the microcontroller offers a lot more options, but seems a lot easier that way, no?

Then again, I didn't know the ps2 had analog outputs :confused:

Adrenalynn
10-22-2008, 05:31 PM
I don't believe it does have analog outputs. Mine doesn't. It's a horribly complicated digital protocol. . .

DresnerRobotics
10-22-2008, 05:44 PM
The Joysticks are just analog pots. Original PS2 ones were anyway, I recall hackin em for a BS2 project.

Adrenalynn
10-22-2008, 10:01 PM
The joysticks, yes. I'm not sure what that would do for you though since they're fed through a microcontroller before being output.

Snaykbt
10-23-2008, 01:55 AM
Tried that. Works opposite of what you would think. As you turn the pot, instead of reducing the effect of the joystick, the motor begins to turn - not the desired result. Weird. Maybe I'm not hooking it up right.

Dave

Snaykbt
10-23-2008, 02:02 AM
I used the PS2 joystick originally. It can be wired to the analog inputs on the speed controller and works just like the phiget joystick I started using. Not as clean though.

Dave

jes1510
10-23-2008, 04:30 PM
You could decrease the voltage on the pot. That should give you more throw around a particular area.