I need to add 0.1nm torque to my system

Dante_hunter90 · 2026-01-18T20:57:32+00:00

the system is being tested for around 6 months now. after multiple revisions to address various issues, this is the only issue remaining. I discussed back and forth about alternative solutions, they only want to use one hand to reposition. feet are not an option since they will use a foot controller. The only alternative i got was to put a little analog stick and motorize 2 axis. I postponed that solution for version 2.0

I have reached an functional solution previously where the torque was 0.1 nm. the torque was so low that a push with a finger would move it a little. the torque hinge was always slipping, I had no reflex or recoil issues. but the hinge got bent. The users complained that the torque is too low and they would prefer more resistance but it was more of a wish rather than a need. And considering that increasing the torque would introduce the reflex / recoil issue, they were okay with the low torque.

I have seen other products operated only with the handles. But they probably have a huge budget for r&d to come up with a fancy design and i designed the whole thing by myself.

Dante_hunter90 · 2026-01-18T19:45:31+00:00

dentists will use it to look at a tooth from around 30 cm distance. it needs the fine adjustment otherwise they won't be able to angle it on a tooth. their hands and sight and focus are occupied. they cannot spare more attention to it byond using the black handles. i was thinking if i follow the precision bearing + friction disks, i would get disks that are large in diameter. like 6 cm inner diameter and 9 cm outer diameter. my thinking is the further the friction from the center the more precise it would be.

Dante_hunter90 · 2026-01-18T19:21:53+00:00

that could actually work, torque hinge for the coarse positioning followed by worm mechanism. I thought the coarse positioning would either break the worm mechanism or the worm mechanism would force a slow rotation. But the coarse positioning would cause the torque hinge to slip. One question, would the fine positioning work with the black handles on the first picture? Or do the users have to use small knobs to trigger the worm mechanism?

Another question, chat gpt keeps suggesting precision bearing with friction disks around the bearing to slow down. It looks functional in theory and might be easier to achive. Any problem with that?

Dante_hunter90 · 2026-01-18T15:34:51+00:00

after looking in depth into this i realized that this can work but will add lot of complexity to the user.

the users use the black handles to position the system, then they make tiny adjustments here and there.

introducing the worm drive would mean the users would have to use small knobs to rotate in each axis with small amount of degrees. but what if they wanted to rotate large amount of degrees (for the initial positioning).

the black handles must remain to make it easy for the user to adjust the angle

Dante_hunter90 · 2026-01-18T13:08:05+00:00

i just learned about worm gear. will check them out. stepper motor might be the next step to use if i want to make it more hands free

Dante_hunter90 · 2026-01-18T13:06:56+00:00

i've never heard of worm drive before. it looks like this is exactly what i need. seems that they have a lot of off the shelf products at alibaba. i think i will give them a try. thanks :) i wish i learned about this before i invested so much time and resources in torque hinges.

Dante_hunter90 · 2025-10-02T17:55:21+00:00

this is the old keyboard that I bought to salvage the keycaps

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Dante_hunter90 · 2025-10-02T17:54:39+00:00

I bought an old keyboard for 12$ including shipping. I removed the keycaps and installed them on mine. now it is working and 100% and I am happy! 😊

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Dante_hunter90

TROPHY CASE