French Nemeus Develops Long-Life Connected Collar for Cattle Monitoring
French electronics engineering company Nemeus has developed Mozaë, a connected cattle collar commissioned by the Seenergi Group and Gènes Diffusion. Combining LoRaWAN, Bluetooth LE and Nordic’s nRF52840, the device targets remote herd monitoring, scalable updates and multi-year battery life.
Developed for a Livestock Advisory Group
Nemeus develops custom secure RF and IoT systems, covering hardware, embedded software, industrialisation and production support. For Mozaë, it designed the electronics, firmware, manufacturing documentation and production test environment.
Seenergi is a French livestock advisory group comprising Conseil Élevage 25-90, Littoral Normand, Origenplus, Seenorest and Seenovia. Together with Gènes Diffusion, it sought to develop its own cattle-monitoring sensor for professional livestock operations.
Key requirements included responsive heat and calving detection, reliable connectivity for outdoor herds far from a gateway, fleet-wide firmware updates, optimised cost and a target battery life of more than eight years.
Monitoring Animal Activity and Key Events
Attached to the animal’s collar, Mozaë analyses motion and temperature data. It supports the detection of heat cycles, calving events, feeding behaviour, and periods spent lying, standing and resting.
LoRaWAN transmits statistical data for use in the Mozaë web and mobile monitoring applications. This gives farmers ongoing visibility of their herd and supports decisions at important stages in an animal’s life.
According to Nemeus, the solution is deployed on more than 2,000 farms and 150,000 cattle, with a reported heat-detection rate of 95 percent.
Single-Controller Design Reduces Complexity
The nRF52840 multiprotocol SoC manages accelerometer acquisition, embedded processing, Bluetooth LE and application logic. An external LoRa transceiver handles LoRaWAN communication in the 868 MHz band.
Nemeus selected a single-controller design instead of separating Bluetooth LE and application or LoRaWAN functions across two processors. This removes inter-processor communication and redundant components, reducing PCB complexity, Flash-memory requirements and firmware-management effort.
The collar is powered by a soldered LS14500 lithium cell in an IP69K resin-potted enclosure. Low quiescent current, controlled radio duty cycles, sleep strategies and the nRF52840’s integrated DC/DC converter manage the energy budget during LoRaWAN transmission peaks.
Bluetooth LE for Fleet-Wide Updates
Bluetooth LE supports sensor pairing, configuration, local status readback and firmware updates from a smartphone. A farmer can update one collar, which then distributes firmware to other tags over Bluetooth LE.
The mechanism builds on Zephyr’s DFU stack and adds Nemeus-developed low-power advertising and scanning logic. Several updated collars can act as distribution sources, reducing manual handling while limiting the effect of updates on battery life.
From Data Collection to Industrial Product
The project started with a proof-of-concept sensor that collected raw accelerometer data on a microSD card. This data supported development of Seenergi’s heat- and calving-detection algorithm, which is integrated into the industrial device.
Nemeus created end-of-line test scenarios and the associated production toolchain. The company also continues to support Seenergi with log and failure analysis, automated test benches, bug reproduction and validation of corrections.
For system integrators and solution providers, Mozaë shows how LoRaWAN and Bluetooth LE can be combined in a low-power livestock-monitoring device. LoRaWAN supports long-distance communication from grazing herds, while Bluetooth LE provides a local channel for installation, servicing and scalable firmware management.
More information about the Nemeus livestock monitoring project: https://nemeus.fr/projets/iotee-capteur-monitoring/