Design of 1-dimensional non-visual list interfaces utilizing the wrist rotation space

Abstract

When a user can use only one hand and it is inconvenient to find or operate a smartphone, a smartwatch can be a convenient substitute for a smartphone. However, since the touchscreen-based input of the smartwatch cannot be operated with one hand without looking at the screen, usability is limited. In particular, interfaces that require continuous variable manipulation, such as list interfaces, have not been suggested how to manipulate them with one hand without relying on time.In this paper, I proposed a concept that quantizes the wrist rotation space and utilizes it as a control space and a display space. Based on this concept, I designed a non-visual list interface that can be implemented using only one actuator. Based on the tasks performed in the list, two types of list interfaces were designed and design spaces were explored to implement them.The first interface is an integer input interface, which is a representative list of ordinal items. By leveraging users' counting ability, a tactile interface was designed, and improved techniques were proposed to reduce the physical and cognitive load that occurs when entering large numbers. It also designed an auditory interface with speech feedback and quantitatively explored the effects of non-speech feedback.It also designed a list interface of nominal items represented by vibration stimulation. In order to implement this in the wrist rotation space, design parameters including the width of the item, the arrangement of items, and the capacity of the list were determined based on the experimental results. Based on the above studies, design guidelines for designing list interfaces in wrist rotation spaces and other motion spaces were suggested.