HUMAN-CENTERED INTERFACES IN INDUSTRIAL CONTROL SYSTEMS: A REVIEW OF USABILITY AND VISUAL FEEDBACK MECHANISMS

Abstract

This study investigates how human-centered interface attributes specifically usability and visual feedback quality affect operator cognition and performance within industrial control systems (ICS) such as supervisory control and data acquisition (SCADA), distributed control systems (DCS), and programmable logic controller (PLC) environments. Drawing on theoretical foundations from human–computer interaction (HCI), situation awareness (SA), and mental workload research, the study operationalizes usability as the degree of learnability, efficiency, error tolerance, and consistency, while visual feedback quality encompasses the clarity, salience, coding, trend fidelity, and timeliness of perceptual cues presented through human–machine interfaces (HMIs). A quantitative, cross-sectional, multi-site case-based design was employed across four industrial sectors, power, petrochemical, water/wastewater, and manufacturing, with 188 operators completing validated Likert-scale instruments, including the System Usability Scale (SUS), NASA-TLX workload indices, and SA/performance batteries. Reliability and validity analyses demonstrated strong internal consistency (α ≥ .86) and discriminant coherence (HTMT < .85). Regression and mediation models, with cluster-robust standard errors by site, revealed that both usability (β = .27, p < .001) and visual feedback quality (β = .21, p = .002) significantly predicted self-reported performance, accounting for 34% of its variance. Mediation analyses confirmed that improvements in usability and visual feedback enhanced situation awareness and reduced workload, which in turn elevated performance, with the SA pathway explaining the larger share of the indirect effects (≈36–39%) and workload accounting for smaller but meaningful contributions (≈11–13%). A significant interaction (β = .11, p = .011) indicated complementarity: each attribute produced greater performance benefits when the other was simultaneously strong, underscoring the synergistic nature of usability and perceptual clarity in human–machine interaction. Collectively, the findings advance an empirically validated framework linking interface design attributes to cognitive and behavioral outcomes in safety-critical operations. The study concludes that integrating usability optimization, visual feedback rationalization, and standardized measurement systems can measurably enhance operator awareness, reduce cognitive load, and improve performance reliability across diverse ICS domains, while calling for longitudinal, multi-modal research to capture dynamic and team-level adaptations in future studies.