“…It has more advantages than sensor technology (Pradhananga and Teizer, 2013;Yang et al, 2011;Brilakis et al, 2011;Teizer et al, 2010). At present, pieces of literature have studied the identification and classification of construction entities (Memarzadeh et al, 2013;Tajeen and Zhu, 2014), the activity recognition of construction entities (Yang et al, 2014;Akhavian and Behzadan, 2015;Kim and Chi, 2019;Zhang et al, 2020;Kim et al, 2018a), the location of relevant entities at the construction site (Kim, 2018;Golparvar-Fard et al, 2013) and the capture of their trajectory (Angah and Chen, 2020;Roberts and Golparvar-Fard, 2019), and the automatic identification of hazards based on the distance and spatial information between identified entities (Fang et al, 2020). Hyojoo et al (2019) presented a vision-based collision warning system based on the automated 3D position estimation of each worker with monocular vision, intending to protect equipment workers from potentially dangerous situations, such as collisions between the equipment and workers in a certain proximity.…”