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Why Project Aura Exists
We live in amazing times. We use smartwatches to count steps and monitor heart rates. We scan barcodes at the grocery store to check calories. We filter our water. But why do we completely ignore the air?
We take about 20,000 breaths a day. Air is the "fuel" that enters our bodies 24/7 — yet most people have no idea what they're actually breathing.
The Problem with Commercial Air Quality Monitors
Most consumer air quality monitors are closed black boxes. You cannot verify:
- How data is processed
- Where it's being sent
- How sensors are calibrated
- Whether the device will keep working after the company shuts down their cloud
Project Aura takes a different approach: you build it yourself, the firmware is fully open source, and all data stays inside your local network.
What Does It Monitor?
Project Aura measures everything that matters for indoor air quality:
Particulate Matter (PM1 / PM2.5 / PM4 / PM10)
These aren't the dust bunnies under your sofa. PM2.5 particles are so small (2.5 micrometers) they pass through your body's protective barriers directly into the bloodstream, causing inflammation. PM10 includes larger particles like pollen and mold spores — critical for allergy sufferers.
Carbon Dioxide (CO₂)
Ever noticed your head getting heavy by midday? At CO₂ levels above 1000-1200 ppm, your brain starts to "suffocate." At concentrations above 1400 ppm, cognitive capacity drops by 50% (confirmed by Harvard studies). Aura tells you when it's time to open a window.
Volatile Organic Compounds (VOC) & Nitrogen Oxides (NOx)
VOCs come from cleaning products, paints, furniture, and even cooking. NOx primarily comes from gas stoves and vehicle exhaust. Both irritate respiratory tracts and can trigger asthma.
Formaldehyde (HCHO) - Optional
That "new car smell" or fresh renovation scent? Budget particleboard furniture, laminate flooring, and adhesives can release formaldehyde — a known carcinogen — for years. The optional SFA30 sensor detects this invisible threat directly.
Temperature, Humidity & Absolute Humidity
In winter, heaters dry indoor air to desert levels (<20% RH). Dry mucous membranes can't protect your body from viruses effectively. Aura calculates Absolute Humidity (g/m³), giving you a more accurate health risk assessment than relative humidity alone.
Barometric Pressure with Trend Analysis
Many people feel migraines or joint pain before weather changes. Aura doesn't just show current pressure — it calculates Delta trends over 3 hours and 24 hours. A sharp pressure drop is your early warning system.
Hardware: No Compromises
Main Controller
Waveshare ESP32-S3-Touch-LCD-4.3 — An all-in-one board featuring:
- Dual-core ESP32-S3 processor
- 16MB Flash memory
- Gorgeous 4.3" IPS capacitive touchscreen (800×480)
- The visual quality difference from cheap displays is like comparing an old TV to a modern tablet
The Sensor Suite
Sensirion SEN66 (Switzerland) — The heart of the system. This single module replaces an entire laboratory:
- PM1, PM2.5, PM4, PM10 (full particulate spectrum)
- CO₂, VOC, NOx (air freshness and chemical pollution)
- Temperature & Humidity
Sensirion SFA30 (optional) — Direct formaldehyde measurement. If you've done renovations or bought new furniture, this sensor reveals the invisible danger.
Adafruit Pressure Sensors — Support for DPS310, BMP580, or BMP581. The device auto-detects which sensor is installed and starts plotting pressure trends.
Adafruit PCF8523 RTC — Real-time clock with battery backup. Aura remembers the exact time even when powered off or working offline. When connected to WiFi, time syncs automatically every 6 hours.
Why Sensirion?
DIY air quality monitors often use a "zoo" of cheap sensors (DHT11, MQ-135, SGP30). These sensors drift over time, cross-contaminate, and provide questionable accuracy.
The Sensirion SEN66 uses Sheath Flow technology — the sensor actively draws air through a protected...
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Chris Lee
Mukesh Sankhla
CiferTech
RupR
Would this work with the Adafruit BMP581? currently the only BMP sensor in stock at adafruit