Task allocation considering shipping safety: Workload resilient interval for inland passenger ship seafarers’ optimal safety performance in real navigation

Maritime operations present unique challenges where excessive seafarer workload can directly impact ship navigation safety. While much of the existing research on seafarers’ workload in dynamic human-machine systems relies on simulation experiments, there is a lack of studies conducted in real maritime environments. Furthermore, research on optimal task allocation with practical applications remains limited. To address these issues, this study investigates the workload values and resilience intervals necessary for optimal safety performance among inland passenger ship seafarers. In order to flexibly distribute seafarers’ workload and prevent ship accidents caused by human factors, this study is devoted to exploring the workload value and resilience interval of seafarers’ optimal safety performance. A real navigation experiment was conducted, during which physical and psychological data from seafarers were collected using an eye movement tracker and the Subjective Workload Assessment Technique (SWAT) scale. A univariate polynomial fitting method was proposed to establish the correlation model between workload and safety performance, as well as between workload and distraction index. The results show that the influence of inland passenger ship seafarer workload on safety performance is inverted U-shaped. When the task difficulty increases, the function will move towards higher workload and the curve inflection point will decrease. The results offer guiding significance and popularization value for the monitoring of seafarers’ health condition and the safety guarantee of ship navigation.