Work in Progress: 6 DOF Arm Uses PICAXE 20M2

I am pretty impressed by your demo!

A few questions, please:

Are those are servo motors or steppers?
How are you 'teaching' the robot? Lots of trail and error or does the robot record a movement and play it back?


Senior Member
Thanks, IJ. Using 6 servos here. I can either hard code it (trial & error) or use an IR remote or keyboard as a teach pendant and use record & playback modes. Lots more impressive stuff to come. Built the arm for a PICAXE feature in upcoming ROBOT magazine, May June issue, due out in March. Part one of my series is on newsstands now, a basic intro to PICAXE.


Senior Member
Thanks, IronJungle! I was pleasantly surprised at the arm's accuracy. The PicAxe is a great controller for this project.
Likin' it!!!! Now I need to build this just because of the cool factor. Added to the list....

A few questions.... How strong does the servo need to be to lift a car? Could this thing run 'forever' or does it need a recalibration from time to time?

BTW, my plan would be to attempt to "repurpose" the gear from this PICAXE experiment that I did. Basically a motor driver experiment for me.


Senior Member
Rock solid repeatability so far, no recalibration needed. But servos are mechanical and certainly have limits. The more you use them, the internal pots and gears will wear out. These Hot Wheels weigh ~35 grams, on the heavy side for an arm this small. So here I'm operating them at a small radius, which keeps the servo loads low. Lifting heavy things at the outer edge of the operating range would dramatically increase the servo loads and cause more wear. I'm not in any hurry to damage the arm, it was built for accuracy, not payload.