Internet of Things-Based Telehealth Monitoring System in Mines: Architectural Concept and Wearable Device Prototype

This work investigates a telehealth monitoring system based on a star wearable wireless sensor network. Using this system, the health of mining workers (blood oxygen concentration, heart rate, body temperature) and mining environment parameters (CO2, temperature, humidity) are measured and real-time monitored at a distance via Bluetooth low energy (BLE) and Wi-Fi technologies for pushing data to the Server for monitoring and warning. With the common use of handheld devices in mines that can only measure in fixed areas, this is quite inconvenient, so there is a need for a wearable BLE mining environment and health monitoring sensor. Compact, low power consumption is recommended and placed on the human body. In addition, measuring health parameters over a long enough period can be the basis for building a data set on worker health to provide reports and guidance on mine safety. A compact, low-power consumption wearable BLE health and mining environment monitoring sensor is proposed and placed on the human body. These wearable sensors have been evaluated in the mine with 0.4 seconds and 99.6% of average packet latency and packet error rate, respectively. The sensors and gateway form a highly flexible star network, capable of adding or removing sensors in approximately 0.3 seconds. The communication distance between two BLE wearable sensors is up to 100 m in free space, and 20 m in the mining environment with many obstacles when the transmitted power on the MCU is 0 dBm.