Graphical User Interface Design Guideline for an Automatic Machine Using an Official Raspberry Pi Touch Screen

Abstract

In this article, we propose a graphical user interface design guideline for an automatic machine using an official Raspberry Pi touchscreen. Experiments have been performed to determine the appropriate button and text sizes in such a way that users can utilize the GUI with speed, accuracy, and usability. The experiments were conducted on five human subjects who are familiar with general electronic device touchscreens. The first experiment was to determine the minimum text size that users can accurately read within 0.5 seconds. The second experiment was to determine the minimum button size and space between two adjacent buttons. Based on the experimental results, a GUI guideline for RPI touchscreens of a specified size handling automation systems is proposed. The guideline suggests the optimal button size, text size, graphic display elements, shape, color, etc. At the end, a case-study GUI, designed with the help of the proposed guideline, has been developed and installed on a 7-inch RPI touchscreen manipulating an automatic thin-film slicing machine. Usability, functionality, and desirability of such a GUI are extraordinarily marvelous.