Spaceflight-inspired pocket optical breath analyzer – 10Hz CO2/O2
We built a pocket-sized optical breath analyzer based on an optical sensor for measuring CO2 and O2. It streams CPET metrics in real time (VO2, VCO2, VE, RER, Tv etc) for breath-by-breath analysis. Functional prototype based custom PCB, mobile app, and web platform are working. Demo videos: https://youtu.be/-DcvRPJJkj0 https://youtube.com/shorts/Ycy8wP4oW2o?si=W0n1Oyof7M37kdta What’s different Instead of electrochemical O₂ fuel cells and typical CO₂ NDIR modules (slower response, periodic replacement/calibration), we use non-consumable optical sensors…
What it does
In the maker’s words, at launch
We built a pocket-sized optical breath analyzer based on an optical sensor for measuring CO2 and O2. It streams CPET metrics in real time (VO2, VCO2, VE, RER, Tv etc) for breath-by-breath analysis. Functional prototype based custom PCB, mobile app, and web platform are working. Demo videos: https://youtu.be/-DcvRPJJkj0 https://youtube.com/shorts/Ycy8wP4oW2o?si=W0n1Oyof7M37kdta What’s different Instead of electrochemical O₂ fuel cells and typical CO₂ NDIR modules (slower response, periodic replacement/calibration), we use non-consumable optical sensors tuned for breath-by-breath dynamics. Our CO2 channel samples at 10 Hz — roughly ~100× faster than NDIR sensors — and does not require an external pump, improving portability. Inspired by the optical, low-drift principles used in spaceflight instrumentation (e.g., Perseverance Mars Rover [1] and NASA PUMA projects [2]), our analyzer uses non-consumable optical gas sensors engineered for stability in harsh environments. Early specs Electronics: custom PCB with ESP32; BLE/Wi-Fi, USB-C, Accelerometer, Magnitometer, PMIC with shipping mode, OTA CO₂ sensor: optical IR, 10 Hz; (supports capnography for medical) O₂ sensor: optical, T63 < 2 s; low drift (< ~1%/year in lab conditions) Flow/Volume: low-inertia turbine (bi-directional), optical interrupter Measurements: in-flow, breath-by-breath Portability: device < 200 g + ~120 g mask (Hans Rudolph) Power: accumulator w/ integrated charging & protection; >4 h typical runtime Maintenance: no annual sensor swaps; no bottled-gas calibration Who it’s for Sport labs, pro teams, elite athletes/coaches, premium fitness clubs, nutrition and longevity labs; medical workflows later (post-regulatory). Limits / open questions Enclosure/thermal design, turbine inertia/lag at very low flows, CO2 calibration method, humidity transients, and cross-flow effects are active work. We’ll publish more validation data (and APIs) as we progress. We’re bootstrapped (no external funding yet). Feedback from practitioners would help us prioritize the roadmap. Happy to answer all questions and brutal feedback welcome! We’re also looking for pilot labs / co-dev partners. * [1] - https://www.nasa.gov/news-release/nasas-perseverance-mars-ro... [2] - https://technology.nasa.gov/patent/LEW-TOPS-16
Does the same job
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