Nordic-powered environment monitor detects sub-optimal conditions in commercial, industrial, and domestic settings

New Zealand company AirSuite has launched an indoor monitor designed to detect and record a range of environmental variables that can affect the health and productivity of people in commercial, industrial, and domestic settings. Employing a range of sensors, the ‘AirSuite Glance’ can monitor carbon dioxide (CO2), temperature, humidity, acoustics, lighting, air pressure, and volatile organic compounds (VOCs), and then notify users of any potential hazards.

Environmental data is recorded every minute and is depicted on the device’s ePaper display using infographics. This data is transmitted to the user’s smartphone via the Bluetooth® LE connectivity of Nordic Semiconductor’s nRF52840 SoC in near real-time, and to the Cloud using the LTE-M or NB-IoT connectivity of the nRF9160 SiP at least every fifteen minutes. The AirSuite Glance is designed for use in a variety of settings, including classrooms, offices, warehouses, retail spaces, and residential buildings.

Wide range of measured variables

“The AirSuite Glance provides one of the highest ranges of measured variables compared to other devices on the market,” says Peter Pooran, CEO of AirSuite. “These sensors allow AirSuite Glance to indicate invisible factors that contribute to sub-optimal conditions in a user’s space and remind users of the unhealthy conditions they may have grown used to. This is important to help users to make informed decisions about how to best maintain their healthy indoor spaces.”

The nRF52840 SoC was selected for both its powerful processor and the generous 1 MB Flash memory and 256 KB RAM

Peter Pooran, AirSuite

The nRF52840 SoC acts as the primary controller for the device, supervising the sensors using its powerful 64 MHz, 32-bit Arm® Cortex® M4 processor with floating point unit (FPU). The SoC transmits the data to the AirSuite Monitor app (available for iOS and Android) on a user’s smartphone or tablet. The data is also transmitted to the ‘AirSuite Cloud’ using the nRF9160 SiP’s multimode LTE-M/NB-IoT modem with integrated RF Front End (RFFE), enabling remote monitoring and control of environmental conditions by facility management, for example.

From the app or web platform, users can manage and receive notifications when environmental metrics exceed or drop below desired ranges. Historic data is also available via the ‘AirSuite Monitor Web Portal’ so users can view trends and compare values for different rooms or sites.

Five year battery life

The AirSuite Glance is powered by an integrated multi-year primary cell battery pack which enables it to function for over five years. There is also a secondary USB connection that enables it to run for longer, even after the battery has depleted. The power consumption of the nRF9160 SiP is class leading. It supports both PSM and eDRX power saving modes. For both LTE-M and NB-IoT the PSM floor current is as low as 2.7 µA, and with an eDRX interval of 655 s the average current is 6 µA for LTE-M and 9 µA for NB-IoT.

During development, AirSuite employed the Nordic Power Profiler Kit 2 (PPK2) to optimize the AirSuite Glance’s software and hardware, helping achieve the desired five year battery life. With each iteration of the product, the PPK2 was used to establish any differences in current consumption and the impact these changes would have on battery life.

“The PPK2 provided a high degree of accuracy at a low cost, meaning our engineers could have one on their desk and one in long-term test rigs,” says Pooran. “AirSuite has configured a power test rig to be able to remotely power profile multiple test devices over extended periods of time. This allows for much more rapid development and testing cycles.

“In addition to the low power consumption, connection range was an important factor in selecting the nRF9160 SiP,” says Pooran. “The nRF52840 SoC was selected for both its powerful processor and the generous 1 MB Flash memory and 256 KB RAM.

“We also benefitted from the nRF Connect SDK [Software Development Kit], which enabled us to leverage Nordic standard libraries, further speeding up testing and development.”