Visual-Tactile warning integration enhances performance and attention under cognitive load in underground mining vehicle operations

Effective warning design is essential for safe underground mining vehicle operation, where drivers must monitor instrument panels under high cognitive demands. This study examined how visual, tactile, and combined visual-tactile warnings affect driving performance, physiological responses, and cognitive workload across different task load levels. Sixty participants completed driving and instrument-monitoring tasks while behavioural, eye-tracking, electrocardiogram, and subjective workload measures were collected. Visual and combined warnings significantly improved reaction speed and accuracy, with combined warnings showing the strongest benefits under high load. Tactile warnings were easily detected but increased mental workload when used alone. Correlation analyses revealed experience-related differences: novice drivers showed higher mental strain, whereas experienced drivers maintained more stable physiological responses and more efficient attentional control. Overall, combined visual-tactile warnings enhanced detection performance, supported visual attention, and reduced fatigue-related physiological fluctuations, offering guidance for safer and more efficient underground vehicle operations.