Low-latency link between personal safety device and smartphone app allows the wearer to contact ‘guardians’ via a single button press in emergency situations
Nordic Semiconductor today announces that Kwema, a Massachusetts, U.S.-based technology start-up, has employed Nordic’s Bluetooth® Low Energy (Bluetooth LE) nRF52832 System-on-Chip (SoC) to add wireless connectivity to two newly-launched jewelry collections. ‘Eve’ and ‘Pacific Ocean’ double as smart personal safety devices in emergency situations or when the user perceives a potential threat.
The nRF52832 SoC’s Bluetooth Low Energy wireless connectivity links the jewelry with Kwema’s companion app on the user’s Bluetooth 4.0 (and later) iOS or Android smartphone. By pressing and holding a button on the device for three seconds, wearers can alert an unlimited number of pre-selected smartphone safety contacts, such as family and friends, of their precise GPS location in an emergency.
When Internet connectivity is not available the app sends a text message via the cellular network ensuring ‘guardians’ still promptly recieve the emergency notification and GPS location. In addition, users can employ an optional feature on the app that locates and immediately alerts other members of the Kwema ‘community’ who are within 500 meters.
Remaining dormant for extended periods and supported by the Nordic SoC’s ultra low power consumption—a result of key SoC features such as the 2.4GHz radio’s 5.5mA peak RX/TX currents, microamp average current and a fully-automatic power management system—Eve and Pacific Ocean both provide CR1220 coin cell battery life of up to one year and beyond.
Nordic’s nRF52832 Bluetooth LE SoC, a member of Nordic’s sixth generation of ultra low power (ULP) wireless connectivity solutions, combines an 64MHz, 32-bit ARM® Cortex® M4F processor with a 2.4GHz multiprotocol radio (supporting Bluetooth 5, ANT™, and proprietary 2.4GHz RF software) featuring -96dB RX sensitivity, with 512kB Flash memory and 64kB RAM. When launched, the SoC was the world’s highest performance single-chip Bluetooth LE solution.
The SoC is supplied with Nordic’s S132 SoftDevice, a Bluetooth 5-certifed RF software protocol stack for building advanced Bluetooth LE applications. The S132 SoftDevice supports Central, Peripheral, Broadcaster and Observer Bluetooth LE roles, supports up to twenty connections, and enables concurrent role operation.
“Long battery life is an important feature of our product. We didn’t want our users worrying about constantly charging another device – even more so a device that could save their lives. The Nordic SoC helped us achieve this requirement,” says Carmina Santamaria, Kwema CEO.
“Another important reason for choosing Nordic’s solution was because the development tools allowed us to focus on our application code while having confidence that the SoftDevice would look after the Bluetooth LE protocol.
“The tools, and the engineering team’s familiarity with Nordic SoC-based Bluetooth LE modules, allowed us to go from the prototyping phase to market much faster,” says Santamaria. “And we couldn’t have been happier with the responsiveness and willingness of Nordic technical support to help us get our designs ready for prototyping and manufacturing.”