Ergonomic Recommendations for Range of Control Panel Angle of Touchscreen Kitchen Appliances

Control panels for kitchen appliances have been designed in various forms and with different design parameter values. Among these design parameters, the panel angle is one of the most important factors influencing the usability and user preference. However, few studies have been conducted regarding the panel angle effects in the context of kitchen appliances. There are only a few safety-oriented regulations or guidelines for kitchen appliance design. Therefore, in this study, the effect of the control panel angle of touchscreen kitchen appliances on their usability was empirically investigated for providing appropriate ergonomic recommendations. A total of six panel angles, namely, 0°, 15°, 30°, 45°, 60°, and 90°, were employed in the experiment in consideration of the design parameter values used in existing slide-in/freestanding ranges. Three usability evaluation measures, namely, visibility, physical comfort, and preference, were employed. For each of the six panel angles, 20 participants performed temperature/power-level setting tasks and then subjectively rated the panel angle in terms of the three measures. The following major findings were obtained: (1) the control panel angle affected the scores of all three measures; and (2) when considering visibility, physical comfort, and preference comprehensively, the panel angle ranges 15°–42° and 15°–19° were recommended as the appropriate and optimal ranges, respectively. The findings of this study may be helpful in the ergonomic design of touchscreen panels for kitchen appliances, which can improve the usability of these panels and reduce human errors and response time in emergencies.