Reverse Engineering the Badger Smart Badge: A Wearable Translator Unveiled
Posted by Mike | September 8, 2025
The Badger Smart Badge by Satellite Displays is a game-changer for real-time translation and captioning, turning your spoken words into readable subtitles on a wearable display. Perfect for bridging language gaps in meetings, this IoT device is compact, smart, and phone-dependent. But how does it work under the hood? Using public data from partners like Nordic Semiconductor and Xometry, we’ve reverse-engineered its architecture, components, software, and manufacturing. Let’s dive into the tech!
Architecture: How It Brings Subtitles to Life
The Badger isn’t a standalone powerhouse—it’s a lightweight badge that leans on your smartphone for heavy processing. Here’s the flow:
- Voice Capture: Dual microphones grab your speech, filtering out background noise.
- Transmission: Audio streams to a smartphone app via Bluetooth Low Energy (BLE).
- Processing: The app uses cloud APIs (like Google Speech-to-Text and Azure Translator) to convert speech to text and translate it (e.g., English to Chinese).
- Display: Translated text beams back to the badge’s e-ink screen in near real-time (~1-2 seconds).
It supports modes like live captioning, note-taking, and static ID display (your name stays visible even when powered off). It’s optimized for low power and privacy, with encrypted data and wearer-focused audio.
Hardware Components: The Heart of the Badge
Based on Nordic Semiconductor’s case studies, the Badger is built around a compact, efficient core. Here’s what’s inside:
Processor and Bluetooth
- Nordic nRF52840 SoC: ARM Cortex-M4F (64 MHz, 1 MB Flash, 256 KB RAM) powers BLE 5.0 and GPIO for peripherals.
- I-SYST BLYST840 Module: Integrates the nRF52840 with a ceramic antenna for low-latency audio streaming (14 mm x 10 mm).
Microphones
- Dual MEMS Mics: Likely Knowles or Infineon models, using I2S for digital audio. One captures your voice; the other cancels noise.
Display
- E Ink Screen: ~2-3 inches, monochrome, 296x128 pixels (est.). Ultra-low power, sunlight-readable, with partial refresh for subtitles.
Battery
- LiPo or Coin-Cell: Likely CR2032 stack or small LiPo with a PMIC for all-day use (<10 mW draw).
Extras
- RFID/NFC: NXP NTAG chip for access control (e.g., hospital doors).
- Button: Single tactile switch for mode/power toggling.
The PCB is likely a flex-rigid single/double-layer board, keeping the badge thin (<2 oz).
Software: The Brains Behind the Badge
The software is split between the badge and phone:
- Firmware: Custom C/C++ on Nordic’s SDK. Manages audio sampling (16 kHz/16-bit), BLE, and e-ink rendering. Supports OTA updates.
- Mobile App: Built with Flutter/ReactJS (iOS/Android, ~50 MB). Integrates Google Cloud Speech-to-Text and Azure Translator for 50+ languages. Handles encryption (TLS/BLE) and real-time monitoring.
Data flow: Mic → BLE → App → Cloud → Text → BLE → E Ink. It’s optimized for low latency but needs internet for cloud APIs.
Manufacturing: From Prototype to Production
Xometry’s case study reveals a polished production process:
- Case: ABS plastic, injection-molded with 0.5 mm walls. Five-part clamshell with snap-fit closure. SLA 3D-printed prototypes for testing.
- Assembly: SMT for PCB (module, mics, display soldered). Ultrasonic welding or snap-fit for the case. Built for 100s-1000s of units.
- Testing: Validates BLE, audio, and display. Programmed with static ID data.
The design prioritizes cost, durability, and quick assembly for B2B markets like healthcare.
DIY It: Build Your Own
Want to replicate it? Use a Pimoroni Badger 2040 ($25) with an e-ink display, add dual MEMS mics (Adafruit I2S), and an nRF52 module. Code with Nordic’s SDK or Arduino for BLE, and fork open-source STT apps like Vosk. Total cost: ~$50-100. Check GeeksforGeeks for tutorials.
Why It Matters
The Badger’s clever design—combining e-ink, BLE, and cloud APIs—makes it a lightweight, practical tool for real-time translation. Whether you’re in a multilingual meeting or a noisy hospital, it’s a glimpse into the future of wearables. Have you tinkered with IoT badges? Share your thoughts below!