Jubilee is an open-source & extensible multi-tool motion platform which can be used for laboratory automation. Let’s make a laser tool…

Science backstory

We’ve been having fun with a little Wainlux K10 5W diode laser ($150/alibaba) to make laser-cut paper microfluidics. To continue the fun, we want to build a frugal self-driving lab device to optimize parameters, etc.

Background info

Apparently we’re not the first to try putting a laser on a Jubilee, but nobody has written about the results

Jubilee uses Duet 3 Mini 5+ which natively support laser engraver/cutter control — assumes a standard 12V laser with 5V active-high PWM signal — so there shouldn’t be any electrical fiddling needed to make this work, just mount it.

First Step: 5 mW 650 nm laser pointer

Objective: Demonstrate that you can successfully operate a laser tool on the Jubilee platform, using a low power Class II laser (glorified laser pointer)

Supplies:

  • 5 mW 650 nm TTL laser diode ($19/adafruit) – this is switched in the same way that bigger lasers are.
  • JST XH 2.5 - 3 pin socket ($1/adafruit) — these are the standard connectors used on TTL lasers
  • JST XH2.54-3Pin cable ($7/amazon) — 80 cm tends to be a common length, but maybe go longer instead? 150cm?
  • Build an adapter from Molex KK254 (on the Duet) to JST-XH2.54

Laser Hello-World with the Duet Mini 5+

The Duet Mini 5+ has a 3-pin Molex KK254 connector on IO6 which provides 5V power, ground, and a 5V PWM signal. Wiring diagram.. This is convenient for testing with a low power TLL-controlled laser pointer.

To enable the laser, add the following to your config.g file:

; Duet 3 Mini 5+
M452 C"out6"    ; Enable Laser mode, on out6, with default max intensity being 255, and default PWM frequency

Send a G-command with S options to set laser power (from 0 to 255)—the example below is the lowest power.

G1 S1           ; S parameter sets power, use the lowest for this test

Note: The laser is only on while the motion is taking place, so you need to be making a move to see it (e.g., G1 X100 S1). You can just do a slow move (change the velocity parameter) so that it stay s on for a while.

Physical structure

TODO: Design Jubilee tool to hold it in place. Good practice in designing tools…good cad practice for students

Safety-third!

Everyone gets two changes at laser eye safety. Don’t look into the laser with your remaining eye.

  1. Get some laser safety glasses

  2. Build an enclosure. You can buy rated acrylic sheets (laser cut them with a CO2 laser) to construct side panels

Next Step: 5W 450nm diode laser

Objective: After establishing that you can do this safely, go for MORE POWER! Class 4 laser

  • LaserTree 5W 450nm laser module ($85/amazon) seems to fit the bill: standard 12V power, 5V PWM control.
  • JST XH2.54-3Pin cable ($7/amazon) — if you don’t have one already from the last experiment.
  • Be sure to get some laser safety glasses

Build:

  • Make an adapter from two inputs: One from the 12V supply and Ground pin; the other from the 5V PWM output that we used above.

Physical Structure

TODO: Design Jubilee tool

Test

TODO: Test

Other things