Aura / build manual
Aura Build Manual
Source the pendant, flash the firmware, run the backend, and pair the app.
What Is Aura
Aura is an open-source AI wearable you wear around your neck. It listens, sees, and transcribes so you do not have to pause your day to take notes. Audio and images are captured and routed to a self-hosted or cloud backend. Summaries and transcripts are accessible from your phone. Built on the open Omi ecosystem. Parts cost approximately $50.
How It Works
01
The microphone captures audio continuously.
02
The camera captures images at set intervals.
03
Both are sent to the backend over Wi-Fi.
04
The backend transcribes audio via Deepgram or Whisper.
05
Images are analyzed via GPT-4o vision or moondream.
06
Everything is summarized and stored.
07
You see it all in the Omi app on your phone.
The ESP32-S3 handles capture and transmission. The backend handles all AI processing. Your phone is the interface.
Bill of Materials
Parts list with estimated costs.
Item
Where to buy
Approx cost
XIAO ESP32-S3 sense
Seeed studio / amazon
$15–24
150mah LiPo × 6
Amazon
$12
Wires
Amazon
$5
3D printed case
Print yourself or order online
$5–10
USB-C cable
Anywhere
Free
Total
Not applicable
~$50
Case STL files are in the Aura hardware folder on GitHub.
Caution
Use only LiPo cells with protection circuits. Never charge unattended. Follow the XIAO ESP32-S3 sense charging current limits (500 mA default).
Hardware Overview
The XIAO ESP32-S3 sense is the core. Camera and microphone are integrated on the board, so no extra modules are needed.
Component
Details
Microcontroller
XIAO ESP32-S3 sense
Camera
OV2640 (built into board)
Microphone
PDM (built into board)
Battery
6× 150mah LiPo cells
Enclosure
Custom 3D printed case
Connectivity
Wi-Fi 2.4 ghz + Bluetooth LE
Dimensions
50 × 68 × 18 mm
Weight
80 g
Battery life
4 h active / 45 min charge
Mount the board, route the battery wires, and snap the case shut. The pendant loop is built into the design.
Flashing Firmware
Clone the firmware repo and flash using PlatformIO:
Connect the board via USB-C, select the correct port, and upload. Verify with the serial monitor:
You should see the boot log with Wi-Fi, camera, and ble initialization.
Backend Setup
The backend handles transcription, image analysis, and memory storage. Deploy with Docker:
Edit .env with your API keys
Required services: Deepgram or Whisper for transcription, Groq or OpenAI for LLM inference, Pinecone for vector memory storage.
Companion App
The Omi app connects to Aura over Bluetooth LE. It shows your conversation history, memory timeline, and device controls. Download the app, create an account, and pair your device. The setup wizard will guide you through. Once paired, you can browse transcripts, search memories, and adjust capture intervals.
AI Providers
Aura supports multiple AI backends. Configure your providers in the .env file.
Service
Purpose
API key required
Deepgram nova-2
Speech-to-text
Yes
Groq lpu
Fast LLM inference
Yes
GPT-4o vision
Image analysis
Yes
Pinecone
Vector memory
Yes
Whisper (local)
Self-hosted transcription
No
Memory & RAG
01
Audio is transcribed, chunked, and embedded into Pinecone.
02
When you ask a question, the query is matched against stored vectors.
03
Matched context is fed to the LLM along with your query.
All memory is private and stored on your own Pinecone index.
Troubleshooting
Device not connecting to Wi-Fi
Verify SSID and password in the firmware config. Confirm 2.4 ghz band is enabled. The ESP32-S3 does not support 5 ghz.
Camera not capturing images
Ensure the camera ribbon cable is fully seated. Try re-flashing the firmware. The OV2640 may need a power cycle.
Audio transcription failing
Check your Deepgram API key in .env. Verify network connectivity from the backend to Deepgram’s API endpoint.
Battery not charging
The ESP32-S3 charges at 500 mA max. Use a quality USB-C cable and power supply. Check voltage with a multimeter.
FAQ
1
How much does it cost to build?
The bill of materials runs roughly $50 for all parts: the XIAO ESP32-S3 Sense, six LiPo cells, wires, and a printed case.
2
Do I need to buy a case?
The case is 3D printed. Print it yourself from the STL files in the hardware folder, or order the print from an online service.
3
Can I run the backend without cloud services?
Yes. Use the local Whisper model for transcription and any OpenAI-compatible server for inference. Pinecone is optional.
4
Is my data private?
You own your data and your device. Run the backend on your own hardware. Audio and images stay on your network unless you choose a cloud backend you deploy and control.
5
Is Aura open source?
Yes. Aura is MIT licensed. Firmware, backend, and app code are in the public Aura repository on GitHub.