from Hacker News

SmartKnob – Haptic input knob with software-defined endstops and virtual detents

by e3a8 on 9/9/23, 6:30 PM with 47 comments

  • by mattclarkdotnet on 9/9/23, 11:45 PM

    Wonderful to see such a well documented open source hardware project! It does show though how much more difficult these are than software projects. 3d design and printing, hardware sourcing issues, the need for careful component selection, very poor support for automation of the toolchain, etc etc. As a minor hardware tinkerer this is both impressive and daunting. Bravo!
  • by seabass-labrax on 9/9/23, 10:44 PM

    I absolutely love that this is open source hardware; there have been multiple circuits available on the web for this kind of peripheral, but nothing even approaching the level of polish that this has.

    If the designer happens to be here, I have a question regarding the circuit. Is there any protection against voltage produced by a user's rotation of the knob? The TMC6300 IC that the schematic shows is directly connected to the BDCM without any intermediate circuitry, but the only 'protections' listed in its datasheet are related to failures related to the motor being used as a motor, not as a generator.

  • by justinlloyd on 9/10/23, 1:09 AM

    Why hello there. I am building a digital jukebox with physical controls and was looking for a few different knob like controls to use to shuffle through tracks. Definitely going to be using this in the project. Thanks for a well documented and Open Source piece of hardware.
  • by _Microft on 9/9/23, 9:49 PM

    Past submission from 2022 with a dozen comments:

    https://news.ycombinator.com/item?id=30646371

  • by jdcarter on 9/11/23, 6:22 PM

    Brilliant execution. I see so many knob-based inputs on home appliances where they have physical detents but the input encoder does not match the detents. Say you turn the appliance on, it starts at setting one, and you need to turn the dial to setting three. Any reasonable person would expect one physical click to take you to setting two, another click would take you to setting three. But I keep seeing devices where the detents are completely arbitrary and you have no idea how many “clicks” it takes to get to the setting you want. This makes the detents actively misleading.
  • by iAkashPaul on 9/10/23, 3:36 PM

    SimpleFOC is one of the best things I learnt after graduation! So many projects can make use of the features, hardware & software both.
  • by babl-yc on 9/10/23, 12:19 AM

    Apparently this and many other cool projects were demoed at Open Sauce in SF https://opensauce.live/
  • by croes on 9/9/23, 10:59 PM

    I definitely need a use case for that
  • by riffic on 9/9/23, 10:13 PM

    there was a microsoft surface dial, not sure if that ever took off or not. I thought there was another product that had this form factor
  • by heliostatic on 9/9/23, 10:43 PM

    This is great! I've been thinking about building something similar for sleep training with my toddler--need something that works in a dark room by feel and has variable intervals. Love it.
  • by dvdkon on 9/10/23, 10:13 AM

    I have been looking for good-feeling large rotary encoders and this looks like the best option available. Having software-based detents means that they are perfectly aligned with the actual trigger, besides all the other flexibility demonstrated.

    Sadly it's too big and costly to put into a dimmer switch, but maybe I'll get it as a general peripheral.

  • by yencabulator on 9/10/23, 3:35 PM

    Make sure to watch the demo videos, they're great.

    https://www.youtube.com/watch?v=ip641WmY4pA and so on.

  • by stavros on 9/10/23, 3:30 AM

    Ooh this project is among the most impressive ones I've ever seen. I saw it years ago and I still remember it (and want one) from time to time. Well done.
  • by TaylorAlexander on 9/10/23, 7:46 AM

    Love to see open source hardware on HN. Great job with this one! If I were not overwhelmed with projects this one would be on my list.
  • by KRAKRISMOTT on 9/10/23, 3:11 AM

    Can the parts be swapped out for automotive grade versions? I need it for the new Tesla Highland since it doesn't have a shifter
  • by leetrout on 9/10/23, 2:52 AM

    These would be awesome for flight simming.
  • by steeve on 9/10/23, 6:38 PM

    I'd love to build a thermostat out of that. That seems like the perfect use case.
  • by Jemm on 9/10/23, 12:51 PM

    The flight/space sim community would love this.