A novel approach to bi-objective optimization of touch-screen installation position for minimizing physical workload and increasing screen visibility. (November 2019)

• Record Type: Journal Article
• Authors: Chihara, Takanori; Seo, Akihiko; Sakamoto, Jiro
• Is Part Of: Applied ergonomics. Volume 81(2019)
• Publication Date: 2019-11
• Subjects: Multi-objective optimization -- Digital human modeling -- Touch screen -- Physical workload -- Joint torque -- Visibility; Human engineering -- Periodicals; 620.82
• DOI: 10.1016/j.apergo.2019.102881
• Languages: English
• ISSNs: 0003-6870

Abstract

Abstract: The aim of this study was to propose a new method for optimizing the touch-screen installation position in order to minimize the physical workload and increase screen visibility. Ten students participated in this study. The participants utilized a touch screen at different installation heights (50, 65, and 80% of stature), tilt angles (0°, 45°, and 90° from the horizontal plane), and having different button sizes (a square with a side of 10, 20, and 30 mm). The joint angles, when using a touch screen, were measured to calculate the joint torque ratios (JTRs). Subjective screen visibility were also determined. The optimal installation position was determined by solving a bi-objective optimization problem consisting of two objective functions. The Pareto optimal solutions for the two objectives showed a range of 1124–1251 mm and 44.4–67.9°. The proposed method determined the optimal installation position of the touch screens. Highlights: A new method for designing the touch-screen installation position was proposed. The physical workload and subjective visibility of touch screens were evaluated. The height and angle design was formulated as a bi-objective optimization problem. The optimal screen height was at 68–75% user height with a tilt angle 46–61°. The optimal installation position of touch screens was investigated.