Bosch Sensortec Unveils AI‑Enabled BME688 Air Quality Sensor to Reduce Virus Transmission Risk

The COVID‑19 pandemic has highlighted the critical need for clean indoor air. Whether at home, in the office, or on public transport, ensuring the air we breathe is safe is more important than ever. Bosch Sensortec has responded with the BME688, an environmental MEMS sensor that couples advanced hardware with AI‑powered software to help reduce infection risk.

MEMS sensors are already ubiquitous, but to keep delivering real value, Bosch Sensortec insists on a tighter hardware‑software co‑design that leverages sophisticated algorithms and embedded AI. According to Vice President and Head of MEMS Product Area, Ralf Schellin, sensor software will increasingly turn MEMS devices into accurate, secure, and personalized systems that adapt to any environment.

In his recent MWS 2021 MEMS Titans Webinar, Schellin highlighted that software adds value not only to the sensor itself but to the entire system.

Every exhaled breath releases tiny droplets that, if infected, can transmit viruses through the air. Lower humidity and temperature prolong aerosol suspension, increasing transmission risk. The BME688 combines four sensing modalities—gas, humidity, temperature, and barometric pressure—alongside AI capabilities to address this challenge.

The gas sensor detects volatile organic compounds (VOCs), volatile sulfur compounds (VSCs), and trace gases such as carbon monoxide and hydrogen in the parts‑per‑billion range. While the BME688 does not directly detect the SARS‑CoV‑2 virus, Schellin says it can markedly reduce infection risk by monitoring VOCs, humidity, and temperature, enabling controlled ventilation or automated air‑cleaner activation.

Dubbed a “digital nose,” the BME688 identifies gases through their unique electronic fingerprints and distinguishes complex mixtures. The sensor requires training via machine learning, which Bosch Sensortec provides through the BME AI‑Studio software. Users can collect custom gas data, train algorithms, and export a final model for integration with the BME library in their projects.

“You can investigate your own use cases and train the system for exactly that application,” Schellin explains.

By temperature‑cycled operation of the BME688’s gas MEMS, different gas mixtures can be recognized and classified. (Image source: Bosch Sensortec)

Standard configurations detect VSCs as an indicator of bacterial growth. The gas scanner can be tuned for sensitivity, selectivity, data rate, and power consumption. BME AI‑Studio enables developers to tailor the BME688’s gas scanner for home appliances, IoT devices, or smart‑home ecosystems.

The software runs on an external application processor; Schellin notes that while the current architecture is separate, future iterations may integrate the AI directly onto the sensor. Bosch has already demonstrated on‑device AI with its BHI motion sensor, underscoring the company’s roadmap.

Bosch Sensortec also offers an Adafruit‑compatible development kit to accelerate adoption.

The BME688’s compact package measures just 3.0 × 3.0 × 0.9 mm. Schellin compares it to the BMM150 magnetometer (1.56 × 1.56 × 0.6 mm) and foresees further size reductions while adding smart features. “When we reach physical limits, we’ll focus on embedding more intelligence rather than shrinking dimensions,” he says.

From sensor design to embedded AI, Bosch Sensortec builds everything in‑house to maximize integration benefits. “If you need ultra‑low power but don’t know the hardware limits, we can’t tell you what’s achievable without building it ourselves,” Schellin explains, though collaboration with partners remains open.

Related Contents:

• Sensor fusion brings multiple benefits
• Medical sensor ASIC embeds ML accelerator
• Sensor-based solutions for vital signs measurements
• Choosing the most suitable predictive maintenance sensor
• Interfacing with modern sensors: Interface design
• Advanced sensor technologies enable personalized air quality monitoring
• Sensor could let smartphone measure vital signs

For more Embedded, subscribe to Embedded’s weekly email newsletter.