Autonomous Detection System for Non-Hard-Hat Use at Construction Sites Using Sensor Technology

Abstract

In this study, we present a novel method of detecting hard hat use on construction sites using a modified version of an off-the-shelf wearable device. The data-transmitting node of the device contained two sensors, a photoplethysmogram (PPG) and accelerometers (Acc), along with two modules, a global positioning system (GPS) and a low-power wide-area (LoRa) network module. All the components were embedded into a microcontroller unit (MCU) in addition to the power supply. The receiving node included a server that displayed the results via both the Internet of Things (IoT) and smartphones. The LoRa network connected two nodes so that it could function in larger areas such as construction sites at a relatively low cost. The proposed method analyzes the data from a PPG sensor located on the hard hat chin strap and automatically notifies a manager when a worker is not wearing the required hard hat at the site. In addition, by utilizing the PPG sensor data, a heart rate abnormality-detecting feature was added based on an age-adjusted maximum heart rate formula. In validation tests, various PPG sensor locations and shapes were studied, and the results demonstrated the smallest error in the circular shaped sensor located at the upper neck (0.56%). Finally, an IoT monitoring page was created to monitor heart rate abnormalities while identifying hard hat use violations via both PCs and smart phones.

Flexible photoplethysmographic sensing devices for intelligent medical treatment

“…[26][27][28][29][30][31][32][33][34][35][36][37][38] Wearable flexible electronic devices exhibit good ductility, [39][40][41] shape adaptability [42][43][44] and biocompatibility. 10,33,[45][46][47][48][49][50] In this study, some results have been obtained by flexible photoelectric detection methods that allowed the acquisition of photoplethysmography (PPG) signals, which are capable of reflecting human blood oxygen saturation.…”

Coflex: Flexible Bracelet Anti Covid-19 to Protect Construction Workers

“…In this specific research field, among the most recent studies Nwaogu and Chan [1] employ wearable technologies to monitor workers in order to understand the impacts of work-related stress, as well as Liu et al [2] and Jebelli et al [3]. Kim et al [4] study a modified version of an off -the -shelf wearable device while Sakhakarmi and Park [5] propose a wearable, tactile-sensing system as a means of communication. Finally Antwi-Afari et al [6] focus attention on insole, in order to analyze the performance of workers for reasons related to safety on site while Kim and Ho [7] on relationship between wearable technologies and privacy.…”

“…The latter involves a bench test phase with subsequent experimentation with reduced functionality. 4.…”