kotstantin86 / bumps

BeagleBone Universal Multi Pololu Steppers

Bumps

BeagleBone Universal Multi Pololu Steppers

BeagleBone Black cape for BeagleG; using 5 stepper driver modules from Pololu.

Bumps is an board to work together with BeagleG, a fast GCode system for CNC/3D printers and one of the first making use of the PRU of the Beaglebone Black for extremely fast step generation.

Find the current version from June 2015 shared on OshPark. Or use the Gerber files directly.

Version History

• Version 0.1 March 2014 ; 5 Stepper drivers, 2 Power PWMs, 2 small PWM, 2 aux outputs.
• Version 0.2 June 2015; small revision of otherwise great first board (fix a missing pullup and wrong solder-mask at one place).

Current work

Work in progress on 0.3 hardware update.

Version 0.3 is work in progress with some changed FETs and other little changes (see illustration below) but also there is a bigger change (in branch drv8825-direct) work in progress to directly use the drv8825 drivers without Pololu modules.

Features

• Simple, mostly passive board with cheap components.
• Single supply; no separate 5V needed:
  • 5V switching supply to power the BeagleBone from motor voltage (12-36V).
  • Local 3.3V power supply to not put any strain on BBB 3.3V
• 5 slots for Pololu-compatible stepper driver boards.
• 1 Emergency switch input, directly wired to hardware-reset stepper drivers.
• 2 high power PWM (Motor voltage, ~20A)
• 2 Open Collector PWM for smaller loads (Up to 20V, ~2A)
• 2 Open Collector Auxilliary Outputs (Up to 20V, ~2A)
• 3 endswitch inputs.
• 3 temperature sensor inputs.

The following illustrations represent the current work in progress:

In real life, the March 2014 version (essentially identical to the June 2015 version):

• Board fabbed by http://oshpark.com/
• Solder paste dispensed with http://github.com/jerkey 's 3D printer, using a program to translate a KiCAD file to GCode (https://github.com/hzeller/rpt2paste ) .. the whole thing made it to Hackaday: http://hackaday.com/2014/04/02/dispensing-solder-paste-with-a-3d-printer/
• Assembled using a self-made vacuum tweezer https://plus.google.com/u/0/+HennerZeller/posts/b3NbB7NzQcM
• Early test of the system http://youtu.be/hIEY9077D64