Robot Arm Position Feedback

[Magnus]

Does anyone have a schematic showing how to use potentiometers (or something else) as position feedback for, say, a robot arm elbow, shoulder etc.? I'm using D.C. motors (because they are more powerful than servos) for my robot arms and wanted to be able to have it move to a certain position and stop or return to a certain position. Or are there better ways of doing this? It would also be useful to have a circuit to return the head or torso to the front and center position automatically. Thanks guys!

[Razor Concepts]

You really don't need a schematic (I assume you are using microcontrollers). Just hook up the potentiometer an ADC port and you're set.

[frodo]

yes but on the potentiometer diagram picture, it has a resistor with an arrow. which pins are the resistor (in series) pins on the pot and which pin is the turny bit on the pot?

[cosminprund]

Does anyone have a schematic showing how to use potentiometers (or something else) as position feedback for, say, a robot arm elbow, shoulder etc.? I'm using D.C. motors (because they are more powerful than servos) for my robot arms and wanted to be able to have it move to a certain position and stop or return to a certain position. Or are there better ways of doing this? It would also be useful to have a circuit to return the head or torso to the front and center position automatically. Thanks guys!

Take a look at the OpenServo project, what you're doing is essentially what they're doing. You'll find schematics there, you'll also find PCB layouts there (those the layouts are for surface mount components). You can go with what they're doing or you can implement your own PID algorithm on your choice of controller.

[Admin]

All I can say is, just start reading:
http://www.societyofrobots.com/robot_faq.shtml