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Week 15

Assignment - System Integration

  • Design and document the system integration for your final project

See Assignment Details

Systems

Power
Input 220V
Rating 12V, 20A

Arduino accepts 12v. Arduino provides 3v3 and 5v connections for OLED and SD Card reader.

Spade connectors on 12V terminal wires. Used higher AWG 12 v wires.

Shortened and routed 12v cables. Use 3D-printed zip tie mounts.

Cycling?

Not tested.

Have plugged and unplugged. Possibly unsafe for MCU?

Burn in?

Not tested.

Longest run time was 15 mins.

Fuzzing?

Not tested.

  • Basic file validation, done by file extension. Didn’t in the end add a cutting/motion system, so didn’t require a g-code interpreter.
  • Tried a Resistance Ladder to reduce pins required. Failed because of complication of multiple button presses(!). As a result moved from Xiao to Arduino Mega.

Material Handling

Good:

  • Rollers can be adjusted.
  • Paper on roller is stable and rolls very easily.

Bad:

  • Paper rolls too easily.
  • You need to unscrew a part to fit a new roll! :(
  • Paper skews with use. And is hard to fix.

I tried to slow the paper by building a vacuum table. Added

Digital Control

Approach: SD Card Reader, minimal interface on machine. SD Card reads successfully on Arduino Mega Shield. TBC on Custom PCB.

Software on Laptop only. Didn’t include G-Code interpretation in v0.4.

  • Button Trigger, fall back.
  • Laser job completion trigger (physical), better.
  • Laser software completion trigger, even better.
  • Paper Movement G-Code + short jobs for external laser cutter, even betterer.
  • Integrated System, best.

Structure and Enclosure Development

Levels:

  1. Circuits in a box
  2. More rigid: Redesigned and made supports for rod mounts out of CNC’s plywood. Added a base from plywood also.
  3. Added: Wiring Mounts! (Designed Wire Routing and mounted to back)
  4. Added: Handles! (has now survived a small drop test!)
  5. Added: Electronic Enclosures, simple 3D printed boxes.
  6. Add enclosure for protection from laser/particles/dust.
  7. Enclose project for integrated system (for v1.0!)

Output

  • Collected with a tray. Add a hard edge for better tearing?
  • Tabs keep cuts in place until assembly. This is inconsistant, sometimes intersects object slice and sometimes doesn’t get close enough to break off easily. Doing intersections on every slice too expensive for 0.4mm layers.
    • Another idea, make a mask area, contour it
  • Cutting files generated in .SVG format.
  • Added Number tags on each cut to help with assembly. In application design, number text outlined. Script necessarily flattened text outline array (maybe just a Grasshopper thing!), and put different tags into different slices, so I made a new typeface, with special numbers for this purpose. Possible to revert to raster engraving, but adds too much time. TBD…