This study employs Neon eye tracking, SART, and the Emotiv Epoc Flex 32-channel EEG to assess visual attention, situational awareness, and cognitive load with high precision. Key metrics include fixation duration, fixation count, saccade amplitude, saccade velocity, pupil diameter, SART scores, and spectral power in the occipital cortex, providing a comprehensive neurophysiological perspective on visual processing and awareness.
Abstract
The use of exoskeletons has the potential to improve construction ergonomics and safety by augmenting the musculoskeletal system of the worker’s body. However, the use of exoskeletons has been shown to have unintended consequences as a result of biomechanical mismatches or heightened cognitive load, which may be aggravated during the use of this device for demanding construction-related tasks. This study aims to investigate the user’s experiences of active back support exoskeletons by assessing the impact of their use on users’ visual attention, situational awareness, and visual cognitive load during the construction-related task. Using construction framing task as a case study, an experimental study was conducted where eye tracking, electroencephalogram, and Situational Awareness Rating Technique (SART) were used to capture objective and subjective data for the evaluation of users’ visual attention, situational awareness, and visual cognitive load. The results show that the area of interest is fixation-based metrics, and saccade-based metrics reports show that the use of active back-support exoskeleton reduces visual attention and situation awareness of the users. This result is corroborated by the SART scores indicating reduced situational awareness when using the exoskeleton. Both pupillometry, which evaluated the change in the pupil diameter of the eye, and the theta power spectral density of the occipital region of the cerebrocortical part of the brain, indicated an increase in the visual cognitive load of the exoskeleton users. This study revealed that aBSE users experience reduced attention and situational awareness, corroborated with heightened visual cognitive load due to depletion in mental resources as a result of motor coordination and planning during construction-related tasks. Additionally, this study revealed how EEG sensors and eye-tracking devices could be used interchangeably in assessing visual cognitive load on sites by reducing the need for multiple sensors in assessing users’ experience. Lastly, this study contributes to Kahneman’s Capacity Model, providing the application of this theory in understanding the concept behind the depletion of cognitive resources during the use of exoskeletons for demanding construction tasks.
Methodology
