Semi-anonymous product supervisor and maker Tristam R. has added a voice assistant to his sensible house, however with out counting on off-the-shelf options — by rolling his personal privacy-respecting model based mostly on an Espressif ESP32 microcontroller and providing Dwelling Assistant assist.
“Final yr (2023) was Dwelling Assistant’s Yr of the Voice,” Tristam writes of the venture, “so I assumed there’d be no higher method to begin 2024 than by constructing my very own Dwelling Assistant powered sensible speaker. It is based mostly on an ESP32-LyraT dev board, which does not appear to be broadly accessible [but] you possibly can seize one on AliExpress or Amazon.”
The Espressif ESP32-LyraT improvement board is constructed particularly with voice-controlled initiatives in thoughts, pairing an ESP32-WROVER-B module with microSD storage growth with built-in audio capabilities together with on-board amplification and two microphones for near- or far-field recording. Crucial to a voice assistant venture is its means to acknowledge “wake phrases” — phrases or brief phrases that convey the system out of sleep and begin lively recognition of spoken instructions, as with “hey Siri” or “Alexa.”
Elsewhere within the construct is an Adafruit Neopixel Stick, which serves as a highly-visible indicator of when the wake phrase has been detected, and a Dayton Audio DMA45-4 1.5″ driver for the system’s responses. Every little thing is housed in a custom-built 3D-printable chassis, offering a mounting level for the driving force, a cut-out for the LED strip, and an higher part that covers the ESP32-LyraT board whereas leaving its capacitive touch-inputs uncovered and its microphones free to hear out for instructions.
For software program, Tristam turned to the ESPHome firmware with a voice pipeline configured for management of Dwelling Assistant by means of spoken instructions. This makes use of the open-source Whisper mannequin to carry out native speech recognition and Dwelling Assistant’s in-house Piper speech synthesis mannequin for responses — all of which runs on the Dwelling Assistant server itself, slightly than on the ESP32 microcontroller.
The construct makes use of a custom-designed 3D-printed chassis housing the speaker, LED strip, and the ESP32-LyraT board on the high. (📷: Tristam R.)
The completion: a material cowl for the entrance, which hides the speaker and naked LED strip. “Print the body STL that is on Printables after which glue some black (or no matter color you need) cloth onto it,” Tristam writes of this a part of the construct course of. “I used [some] superglue and a few garments pegs to carry the material in place whereas the glue cures. It is best to now have a neighborhood voice assistant that’ll allow you to management your sensible house with out the fear of Mr. Bezos listening in or the reliance on an web connection!”
The total construct information is on the market on Tristam’s web site, whereas the STL information for the case have been uploaded to Printables below the Artistic Commons Attribution-NonCommercial 4.0 Worldwide license.