The aim of this project is to create a system that could be worn by each of the workers and transmit its sensor data to a base station located in the room.

We therefore used the Bluetooth 4.2 (BLE) protocol in a star topology with a base station being a computer for display and storage.

The embedded system consisted into a Nordic Semiconductor wireless MCU along power supply/management, vibration motor, LED and a FFC connector to connect multiple sensors. The base station connected to the PC was containing the same Nordic Semi chip along with a UART/USB interfacing chip. The data were then displayed on the PC. By the architecture of our system, we could connect as many node to the base station as the Bluetooth bandwidth would allow, which represents hundreds of nodes, as each node only transmit few times per minutes (which is selectable). The system is bidirectional, meaning that the Base station could send notifications/warning to the embedded system and vice versa. We designed the PCB with Eagle (Cadsoft) and had it manufactured in China, soldered in Qatar by ourselves. The code was made in C with Segger Embedded Studio. The Graphical application was written in Python with PyQt for a quick prototyping .