Development of a virtual reality system usability questionnaire (VRSUQ).

Virtual reality (VR) has gained significant attention as a technology that provides immersive experiences similar to the real world. In order for a VR system to be accepted, usability needs to be guaranteed. Accordingly, VR-related researchers are continuing their efforts to improve VR systems by conducting usability evaluations. However, existing studies have limitations in that they cannot comprehensively evaluate the detailed properties of VR systems by using questionnaires developed for general product usability evaluation or focusing only on some usability aspects of VR systems. This suggests it may be difficult to fully capture usability issues in a VR system, and that it is necessary to develop a usability evaluation tool that reflects the specific characteristics of the VR system. Therefore, this study develops and proposes the Virtual Reality System Usability Questionnaire (VRSUQ). In the development of the questionnaire, items were structured based on a literature review and discussions with experts. To account for the diverse characteristics of VR systems, the validity of the questionnaire was verified through both exploratory and confirmatory factor analysis, utilizing data obtained from three distinct experimental studies that employed different VR systems. In addition, by comparing the results of VRSUQ with the results from the System Usability Scale, which is widely used for perceived usability evaluation, alternative possibilities for using VRSUQ are presented. Further testing on various VR platforms is needed to ensure the reliability and validity of VRSUQ, and as results from using VRSUQ are accumulated, it is expected to be widely used as a more powerful and robust VR-specific perceived usability evaluation tool.

A comparative study of navigation interfaces in virtual reality environments: A mixed-method approach.

Recently, motion-based navigation interfaces have been widely utilized in virtual reality (VR) environments. However, improper navigation interfaces can negatively impact the VR experience, and because different interfaces have different characteristics, the navigation experience may vary. Although comparative studies have been conducted with various interfaces, information obtained by focusing on qualitative evaluation was limited. Thus, this study explores the effects from three navigation interfaces (walking-in-place (WIP), joystick, and teleportation) on user performance, sense of presence, workload, usability, and motion sickness through a mixed-method design. Twenty-one participants were asked to perform a navigation task using selected navigation interfaces. The results indicated different advantages and disadvantages in the navigation interfaces for each evaluation metric. In particular, it was found that more research on user safety is required for the WIP interface. The findings of this study are expected to contribute to the development of guidelines for applying navigation interfaces to specific VR environments.

Mining affective experience for a kansei design study on a recliner.

As the technical performance of products progresses, it is becoming more important to design products that satisfy customers' affective experiences. Hence, many studies about Kansei engineering or Kansei design have been conducted to develop products that can satisfy customers' affective experiences. In the Kansei design method, it is important to select affective variables related to the design elements of the product in order to accurately grasp the emotions of customers. Therefore, this study seeks to develop an affective variable extraction methodology that can reflect users' implicit needs effectively and efficiently. In this study, users' affective variables were extracted from online reviews and classified using a self-organizing map (SOM). For verification, the study selected the Amazon e-commerce service and performed a product experiment on recliners. The experimental results show that the most frequently used affective variable in the use of recliners is 'comfort', which is related to various affective variables. In addition, 15 clusters for affective experiences of recliners extracted from Amazon.com were classified through the SOM. The findings suggest that text mining techniques and the SOM can be used to gather and analyze customers' affective experiences effectively and efficiently. The results of this study can also enhance an understanding of customers' emotions regarding recliners.

A systematic review of hybrid brain-computer interfaces: Taxonomy and usability perspectives.

A new Brain-Computer Interface (BCI) technique, which is called a hybrid BCI, has recently been proposed to address the limitations of conventional single BCI system. Although some hybrid BCI studies have shown promising results, the field of hybrid BCI is still in its infancy and there is much to be done. Especially, since the hybrid BCI systems are so complicated and complex, it is difficult to understand the constituent and role of a hybrid BCI system at a glance. Also, the complicated and complex systems make it difficult to evaluate the usability of the systems. We systematically reviewed and analyzed the current state-of-the-art hybrid BCI studies, and proposed a systematic taxonomy for classifying the types of hybrid BCIs with multiple taxonomic criteria. After reviewing 74 journal articles, hybrid BCIs could be categorized with respect to 1) the source of brain signals, 2) the characteristics of the brain signal, and 3) the characteristics of operation in each system. In addition, we exhaustively reviewed recent literature on usability of BCIs. To identify the key evaluation dimensions of usability, we focused on task and measurement characteristics of BCI usability. We classified and summarized 31 BCI usability journal articles according to task characteristics (type and description of task) and measurement characteristics (subjective and objective measures). Afterwards, we proposed usability dimensions for BCI and hybrid BCI systems according to three core-constructs: Satisfaction, effectiveness, and efficiency with recommendations for further research. This paper can help BCI researchers, even those who are new to the field, can easily understand the complex structure of the hybrid systems at a glance. Recommendations for future research can also be helpful in establishing research directions and gaining insight in how to solve ergonomics and HCI design issues surrounding BCI and hybrid BCI systems by usability evaluation.