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Intermediate. Assumes working knowledge.
2.8M views4 years ago2 recommendations
HardwareSystems programmingEmbedded systemsElectronics
Scott Bezek demonstrates SmartKnob View, an open-source haptic input device using a brushless motor for software-defined detents.
Introducing the SmartKnob View: an open-source input device with software-configurable endstops, virtual detents, haptic touch feedback, and a round LCD. Since you can't feel the detents through the video, make sure to turn up the volume so you can at least hear them, particularly the fine-grained detents toward the end of the video. A brushless gimbal motor is paired with a magnetic encoder to provide closed-loop torque feedback control, enabling virtual endstops and detents. Internally, everything is powered by an ESP32, with a TMC6300 BLDC motor driver, HX711 strain gauge ADC, VEML7700 ambient light sensor, and more! I'll have a lot more to share about this project in the future, like a design and assembly overview, so make sure you're subscribed if you want to see more! And follow me on Twitter (@scottbez1) for mini-updates, like this demo of the PCB-mounted strain gauges: twitter.com/scottbez1/status/1499510448864915465 or a sneak-peak of the internals: twitter.com/scottbez1/status/1502335685918814212 Open source project: github.com/scottbez1/smartknob 🛒 Related hobby electronics items (affiliate links help support the channel, at no cost to you): Round 240x240 LCD module (GC9A01): amzn.to/3xDpafs (This is a breadboard-friendly module using the same circular LCD panel used in the SmartKnob - useful for prototyping. If you want just the raw LCD panel, see the BOM in the project GitHub for more info) Highly recommended soldering iron - TS100: amzn.to/3Olswd0 (I use the Ralim/IronOS firmware, and built a barrel jack extension cable with flexible silicone-insulated dual-core wire for better maneuverability) Load cell amplifier - HX711: amzn.to/3uS0b66 (This is a breadboard-friendly module for using the same HX711 load cell amplifier used in the SmartKnob for detecting force applied downward on the knob, along with the strain gauges below) Strain gauges BF350-3AA: amzn.to/3uQLSij (Strain gauges like these are used to measure the PCB flex to detect presses on the knob) If you liked this video/project and would like to support other cool projects, I'd love to have your sponsorship support on GitHub: github.com/sponsors/scottbez1/ This project was greatly inspired by @JesseSchoch 's video "Haptic textures and virtual detents" so definitely check that out too: youtube.com/watch?v=1gPQfDkX3BUWhat people say. Highly recommended as an impressive showcase of open-source hardware and haptic feedback engineering.
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