IoT System for Monitoring of Workers at Height

Work at height is considered a high-risk task due to the exposure of personnel to non-daily or natural factors for the human being, such as changes in temperature, position and limited displacement, which might affect the person’s metabolism. In Colombia, over the years, this activity has represented a significant number of accidents and deaths. In order to be able to detect a possible eventuality or issue with the worker at height, this project proposed and developed an IoT prototype system to monitor biological variables, such as, heart rate and blood oxygen level, and variables of protection for the worker, such as the securing of the carabiner on the line of life and the height at which the worker is positioned. In the materials and methods section, the system architecture and its connections are explained. To measure heart rate and blood oxygen level, the plethysmography technique is selected, a high-resolution barometer is selected to measure the worker's height, and a pressure sensor is selected to measure carabiner securing. This section also explains the development of electronic instrumentation and the connection of the different modules to guarantee the acquisition of information and its sending to the cloud. The results of the characterization of the prototype indicated errors of 3.56% for the heart rate, 1.1% for the blood oxygen level and 10% for the carabiner securing measurement. As a conclusion the IoT system was designed, implemented and verified for the proposed variables. The system allows real-time measurements and connectivity between physical variables and the cloud.