Physiological and Eye Tracking determinants as markers of Skill Acquisition in Manual Inspection
Authors: Godhania Sacha , Eimontaite Iveta , Fletcher Sarah 
Published: June 2024

Skill acquisition in the manufacturing industry is a crucial aspect of optimising performance, efficiency, and safety in complex work environments. Human factors play a significant role in skill acquisition, encompassing factors such as cognitive processes, perception, decision-making, and physical interactions within the work environment. Eye tracking data has emerged as a valuable tool for studying skill acquisition (Toker et al., 2014) in the manufacturing industry, offering insights into workers' visual attention, cognitive strategies, and task performance. Currently, in manufacturing settings, skill acquisition involves the mastery of various tasks, from operating machinery and assembly line processes to quality control and troubleshooting. Effective skill acquisition is essential for ensuring consistent product quality, minimising errors, and maximizing productivity. Human factors, including attentional processes, perception, and decision-making, influence how workers acquire and apply new skills in these dynamic and often high-pressure environments (Mark et al., 2020).The aim of the current research is to understand the duration required to acquire skills through procedural learning and the transition to routine development occurs when leaned behaviour becomes habitual and routine. Furthermore, the research also aims to understand how mental and physical fatigue impact their performance with manual quality control tasks. The study aims to showcase preliminary results regarding human factors and performance variations. Participants completed an inspection task that involved an industrial component (monitor) for their serial number, visual and tactile quality under a control condition: control (no manipulation) measuring physical demand and stress levels during each monitor inspection. Physiological measures were captured using a Empatica E4 wristband (capturing electrodermal activity (EDA), heart rate, skin temperature) and eye tracking was performed with Tobii Glasses 3, as well as subjective measures of performance via NASA TLX. The results from the physiological data show that the initial 10 minutes of the task showed a positive significant correlation between EDA and NASA Performance score (Spearman rho = .675, p =.016), the second set of 10 minutes positively correlated EDA and NASA TLX temporal demands (Spearman rho = .757, p =.004), while final 10 minutes showed a positive correlation between EDA and NASA TLX physical demand (Spearman rho = .639, p =.025). Such results indicate that skill acquisition over time goes through several stages – individual's anxiety of their performance, then concerns for timely performance, and finally experiencing physical impact – as well as that EDA is good indicator of changing workload demands.The current study will present the findings of the stress and physical discomfort levels, physiological data and preliminary eye tracking data whereby results found that for the initial inspection of the first two components participants move between the instructions for the inspection and the actual inspection, however, analysis of the third component and further components revealed that attention is mainly focused on the component inspection with little fixations towards the instructions. There was also an increase in the development of skill acquisition whereby by participants displayed a decrease in error count (from 1 to 0 over the inspection of 10 monitors), instruction analysis and increase in time of task completions as the average time reduced from 6 minutes 07 seconds for the first component to 1 minute 51 seconds for the last component. (The results from the eye tracking data reveal participants’ gaze patterns during the experiment highlighting the time spent on task comprehension and completion suggesting the skill was acquired during the experimental task. In summary, the current study demonstrates the development of skills through a variety of measures showing temporal progression, mental demand and the physicality of manual handling tasks is a complex process influenced by various human factors, including attention, fatigue, and tactile knowledge. By leveraging physiological data, eye tracking and stress levels the research provides scope into how human skill acquisition is progressive through various factors that can reduce overtime to upkeep and maintain the skills of workers perform in the manufacturing industry.