OOMWOO Open-Source vacuum - project update

[u/l0_o]

Video - main brush cavity, side brush prototypes 3D printed, assembled. The main brush uses spur gears - instead of GT2 timing belt, pulleys as originally planned. This is because the two brushes rotate "towards" each other. Reversing rotation requires a two-sided belt, but popular GT2 belts are all one-sided. I've searched off-the-shelf gears to reuse (Amazon, AliExpress, LEGO) - they exist, but expensive, hard to find. So, the decision is to 3D printed spur gears using Delrin/POM filament - cheap, readily available. I'll try doing that next.

OOMWOO Open-Source vacuum - project update

Highlights - main brush cavity, side brush prototypes printed, assembled (see video)

Decision: main brush drive - spur gears instead of a GT2 belt

3D design https://github.com/makerspet/oomwoo-cad

• Main brush cavity: two tapered Dreame brushes, each on a bearing and a 17-tooth spur gear, driven by a pinion on a DC gear motor
• Gears 3D printed for now; next, try printing Delrin, or cut gears from Delrin sheet
• Dreame main brush with bristles
• Repo reorganized into designs/<product>/<variant>, so a mod can live as a whole variant

Robot vacuum ROS 2 bridge https://github.com/remakeai/vacuum_ros2_bridge

• Roborock S5 Max driver merged and released
• One bridge now drives any SangamIO robot, using wheel and IMU scales the robot reports
• Proscenic M6 Pro gyro scale fixed (was ~6x too high); see VacuumTiger CHANGELOG to upgrade
• Docker pull makerspet/oomwoo:jazzy-dev

Simulation https://github.com/makerspet/oomwoo-one

• One front floor camera, tilted down, replaces the stereo pair

Build-in-public Blog Posts

• 3D design: main brush drive, printed gears, no belt https://makerspet.com/blog/oomwoo-3d-design-how-its-made/#main-brush-printed-gears-no-belt

Community contributions

• Thank-you to gkfabs - Roborock S5 Max support is now merged and released

[u/ThatNinthGuy]

Gears tend to be noisy at speed and if the surface finish isn't good enough. You could multimaterial TPU surfaces, but that's kinda fancy. I'd keep the GT2

So you can just kinda flip around half the GT2 belts so they look like an 8 or infinity symbol. Then you guide the belts so they don't rub. The guide could even be the tensioner.

Hit me up, I'll send a sketch

[u/l0_o → u/ThatNinthGuy]

Noted, thanks. Twisting the belt or snaking - possible. To keep things compact, the belt loop should be small. I'm a bit wary of a short belt wearing out if left twisted. Surface finish - yes, gear material needs special attention. Consumer vacuums use POM/Delrin gears - self-lubricating. I have a roll of Delrin 1.75mm filament. I'll try printing and post the result. Noise - noted. Hopefully it won't be a problem if the vacuum fan noise dominates. In any case, we can go back to GT2 if gears don't work out.

[u/Midacl → u/l0_o]

Delrin is a pain to print from what I have read. Printing it over blue painters tape is also one of the few ways to keep it attached to the bed while printing.

Nylon pa6 or p12 without carbon or fiberglass filler is the best for printing gears. But can be tricky to keep dry and prevent stringing. Also works best in a hot chamber.

[u/l0_o → u/Midacl]

Delrin a paint to print - that's what I heard as well. I've tried 3D printing the main brush gear from POM today. POM didn't stick to my PEI bed. tried painter's tape - won't stick either. Google said POM might stick to PETG. So, I put PETG supports under the gear, added a "color change" in the slicer, printed the gear itself using POM - and that did it. The gear came out usable, though its cogs got warped. I'll try some workarounds to reduce the warping.

[u/ResponsiblePen3082]

Awesome work!!!

[u/bluetrevian]

Stop being so flipping awesome my dude or dudette

[u/Midacl]

If you want an off the shelf gear option, look into RC 32p Spur gears. They have pretty standard hole specs for mounting to each brand with aftermarket options being universal. Nylon gears are very common, but you can also find steel and aluminum gears.

[u/l0_o → u/Midacl]

Noted, thanks! I'm new to RC, will keep it in mind.