Hey! This thing is still a Work in Progress. Files, instructions, and other stuff might change!

Bicep Stepper

by lothar22, published

Bicep Stepper by lothar22 Feb 13, 2013

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4890Views 642Downloads Found in Robotics
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Derivatives for servoholderV1, PistonanticlockV1 and PistonbaseantiV1.stl for using a stepper motor instead of a servo.
Changed the pitch of the screw, as it was too steep for the stepper.

Video of bicep (and hand) in action.


Print stepperholder and StepperPistonbase at normal infill. I use 20%. Print stepperdrive at 100% infill.
No support needed.

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Bicep Stepper by lothar22 is licensed under the Creative Commons - Attribution license.

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Hello! How kgf.cm are Steppers NEMA 17.

Yes, steppers are NEMA 17.

Good evening! Can you provide me with the stepper motor code nema 17?

Aug 25, 2015 - Modified Aug 25, 2015
lothar22 - in reply to andersonhps

The code would be specific to the hardware you are running.
I connect to an "Arduino" chip on a Gertboard (an Atmel ATmega "Arduino" chip on the Gertboard), with a Raspberry Pi.
If you are using an Arduino, you can use the Arduino IDE for it, and include some stepper libraries and use them in your code.
My code was very simple, and used some stepper libraries, link here:.

Photo and drawing connections can expose

The Gertboard manual can guide you for connections to the Pi and installation of the Arduino IDE, so you can program it.
See the link for product info and manual.

I looked at your design and I really enjoyed it.
because I do not have the opportunity to buy HITEc-805bb in Russia do not send a good replacement.
not prompt what model you used the stepper motor, and how to join the Arduino

I use NEMA 17 steppers, same as I use on my Prusa 3D printer.
I connect to the "Arduino" chip with a Raspberry Pi and a Gertboard (an Atmel ATmega "Arduino" chip is on the Gertboard).

Updated the stepper holder...

Wow nice! I would love to see a video when ready on software. Did you
gain or lose, when the arm is totally retracted? You say you are going
to limit the extension, so I would guess you gained retraction. What
stepper Nema did you use?

Didn't lose or gain anything on retraction. Just can't extend fully, but it's not much at all, maybe a few degrees.

Still working on the software. My mad scientist friend is coding it from the ground up. He built the printer board from scratch, starting with an ARM microcontroller and a breadboard. Steppers are NEMA 17.

Sweet! I was just thinking about using steppers in some places when I finish my printer and start working on my own inMoov build.