Multimodal Technol. Interact., Volume 8, Issue 2 (February 2024) – 9 articles

This study investigates accessible and sensitive electrode solutions for detecting touches and squeezes on soft interfaces based on commercially available conductive polyurethane foam. Various electrode materials and configurations are explored, and for electrodes made of conductive threads, the static and dynamic electrical behaviors are studied in depth. In contrast to existing approaches that aim to minimize or stabilize contact resistance, we propose leveraging contact resistance to significantly enhance sensing sensitivity. Suggestions for future researchers and developers when building squeeze sensors based on this material are provided. Our findings offer insights for DIY enthusiasts and researchers, enabling them to develop sensitive soft interfaces for touch and squeeze interactions in an affordable and accessible manner and provide a completely soft user experience. Full article

Deployable kinematic structures can transform themselves from a small closed configuration to a large deployed one. These structures are widely used in many engineering fields including aerospace, architecture, robotics and to some extent within HCI. In this paper, we investigate the use of a symmetric spherical deployable structure and its application to interface control. We present HoberUI, a bimanual symmetric tangible interface with 7 degrees of freedom and explore its use for manipulating 3D environments. We base this on the toy version of the deployable structure called the Hoberman sphere, which consists of pantographic scissor mechanisms and is capable of homogeneous shrinkage and expansion. We first explore the space for designing and implementing interactions through such kinematic structures and apply this to 3D object manipulation. We then explore HoberUI’s usability through a user evaluation that shows the intuitiveness and potential of using instrumented kinematic structures as input devices for bespoke applications. Full article

This paper identifies subgenres of asymmetric virtual reality (AVR) games and proposes the AVR Game Genre (AVRGG) framework for developing AVR games. We examined 66 games “in the wild” to develop the AVRGG and used it to identify 5 subgenres of AVR games including David(s) vs. Goliath, Hide and Seek, Perspective Puzzle, Order Simulation, and Lifeline. We describe these genres, which account for nearly half of the 66 games reviewed, in terms of the AVRGG framework that highlights salient asymmetries in the mechanics, dynamics, and aesthetics categories. To evaluate the usefulness of the AVRGG framework, we conducted four workshops (two with the AVRGG framework and two without) with novice game designers who generated 16 original AVR game concepts. Comparisons between the workshop groups, observations of the design sessions, focus groups, and surveys showed the promise and limitations of the AVRGG framework as a design tool. We found that novice designers were able to understand and apply the AVRGG framework after only a brief introduction. The observations indicated two primary challenges that AVR designers face: balancing the game between VR and non-VR player(s) and generating original game concepts. The AVRGG framework helped overcome the balancing concerns due to its ability to inspire novice game designers with example subgenres and draw attention to the asymmetric mechanics and competitive/cooperative nature of games. While half of those who used the AVRGG framework to design with created games that fit directly into existing subgenres, the other half viewed the subgenres as “creative constraints” useful in jumpstarting novel game designs that combined, modified, or purposefully avoided existing subgenres. Additional benefits and limitations of the AVRGG framework are outlined in the paper. Full article

There is a limited amount of research dedicated to designing and developing computing curricula specifically tailored for students with autism spectrum disorder (ASD), and thus far, no study has examined the effectiveness of an accessible computing curriculum designed specifically for students with ASD. The goal of this study is to evaluate the effectiveness of an accessible curriculum in improving the learning of computational thinking concepts (CTCs) such as sequences, loops, parallelism, conditionals, operators, and data, as well as the development of proficiency in computational thinking practices (CTPs) including experimenting and iterating, testing and debugging, reusing and remixing, and abstracting and modularizing. The study involved two groups, each comprising twenty-four students. One group received instruction using the accessible curriculum, while the other was taught with the original curriculum. Evaluation of students’ CTCs included the analysis of pretest and posttest scores for both groups, and their CTPs were assessed through artifact-based interview scores. The results indicated improvement in both groups concerning the learning of CTCs, with no significant difference between the two curricula. However, the accessible computing curriculum demonstrated significant enhancements in students’ proficiency in debugging and testing, iterating and experimenting, modularizing and abstracting, as well as remixing and reusing. The findings suggest the effectiveness of accessible computing curricula for students with ASD. Full article

This paper presents two gesture-based user interfaces which were designed for a 3D design review in virtual reality (VR) with inspiration drawn from the shipbuilding industry’s need to streamline and make their processes more sustainable. The user interfaces, one focusing on single-hand (unimanual) gestures and the other focusing on dual-handed (bimanual) usage, are tested as a case study using 13 tasks. The unimanual approach attempts to provide a higher degree of flexibility, while the bimanual approach seeks to provide more control over the interaction. The interfaces were developed for the Meta Quest 2 VR headset using the Unity game engine. Hand-tracking (HT) is utilized due to potential usability benefits in comparison to standard controller-based user interfaces, which lack intuitiveness regarding the controls and can cause more strain. The user interfaces were tested with 25 test users, and the results indicate a preference toward the one-handed user interface with little variation in test user categories. Additionally, the testing order, which was counterbalanced, had a statistically significant impact on the preference and performance, indicating that learning novel interaction mechanisms requires an adjustment period for reliable results. VR sickness was also strongly experienced by a few users, and there were no signs that gesture controls would significantly alleviate it. Full article

Existing studies of technology supporting meditation habit formation mainly focus on mobile applications which support users via reminders. A potentially more effective source of motivation could be contextual cues provided by meaningful objects in meaningful locations. This longitudinal mixed-methods 8-week study explored the effectiveness of such an object, Prana, in supporting forming meditation habits among seven novice meditators. First, the Meditation Intentions Questionnaire-24 and the Determinants of Meditation Practice Inventory-Revised were administered. The self-report habit index (SrHI) was administered before and after the study. Prana recorded meditation session times, while daily diaries captured subjective experiences. At the end of the study, the system usability scale, the ten-item personality inventory, and the brief self-control scale were completed, followed by individual semi-structured interviews. We expected to find an increase in meditation frequency and temporal consistency, but the results failed to confirm this. Participants meditated for between 16% and 84% of the study. The frequency decreased with time for four, decreased with subsequent increase for two, and remained stable for one of them. Daily meditation experiences were positive, and the perceived difficulty to start meditating was low. No relevant correlation was found between the perceived difficulty in starting to meditate and meditation experience overall; the latter was only weakly associated with the likelihood of meditating the next day. While meditation became more habitual for six participants, positive scores on SrHI were rare. Despite the inconclusive results, this study provides valuable insights into challenges and benefits of using a meditation device, as well as potential methodological difficulties in studying habit formation with physical devices. Full article

Even though assistance systems offer more potential due to the increasing maturity of the inherent technologies, Automatic Speech Recognition faces distinctive challenges in the industrial context. Speech recognition enables immersive assistance systems to handle inputs and commands hands-free during two-handed operative jobs. The results of the conducted study (with n = 22 participants) based on the counterbalanced within-subject design demonstrated the performance (word error rate and information transfer rate) of the HMD HoloLens 2 as a function of the sound pressure level of industrial noise. The negative influence of industrial noise was higher on the word error rate of dictation than on the information transfer rate of the speech command. Contrary to expectations, no statistically significant difference in performance was found between the stationary and non-stationary noise. Furthermore, this study confirmed the hypothesis that user acceptance was negatively influenced by erroneous speech interactions. Furthermore, the erroneous speech interaction had no statistically significant influence on the workload or physiological parameters (skin conductance level and heart rate). It can be summarized that Automatic Speech Recognition is not yet a capable interaction paradigm in an industrial context. Full article

This paper presents a thorough review of electrical muscle stimulation (EMS) in the context of augmented reality (AR) and virtual reality (VR), specifically focusing on its application in providing kinesthetic feedback. Our systematic review of 17 studies reveals the growing interest and potential of EMS in this domain, as evidenced by the growing body of literature and citations. The key elements presented in our review encompass a catalog of the applications developed to date, the specifics of the stimulation parameters used, the participant demographics of the studies, and the types of measures used in these research efforts. We discovered that EMS offers a versatile range of applications in AR/VR, from simulating physical interactions like touching virtual walls or objects to replicating the sensation of weight and impact. Notably, EMS has shown effectiveness in areas such as object handling and musical rhythm learning, indicating its broader potential beyond conventional haptic feedback mechanisms. However, our review also highlights major challenges in the research, such as inconsistent reporting of EMS parameters and a lack of diversity in study participants. These issues underscore the need for improved reporting standards and more inclusive research approaches to ensure wider applicability and reproducibility of results. Full article

Brain–computer interfaces (BCIs) based on steady-state visually evoked potentials (SSVEPs) have been well researched due to their easy system configuration, little or no user training and high information transfer rates. To elicit an SSVEP, a repetitive visual stimulus (RVS) is presented to the user. The properties of this RVS (e.g., frequency, luminance) have a significant influence on the BCI performance and user comfort. Several studies in this area in the last one-and-half decades have focused on evaluating different stimulus parameters (i.e., properties). However, there is little research on the synthesis of the existing studies, as the last review on the subject was published in 2010. Consequently, we conducted a scoping review of related studies on the influence of stimulus parameters on SSVEP response and user comfort, analyzed them and summarized the findings considering the physiological and neurological processes associated with BCI performance. In the review, we found that stimulus type, frequency, color contrast, luminance contrast and size/shape of the retinal image are the most important stimulus properties that influence SSVEP response. Regarding stimulus type, frequency and luminance, there is a trade-off between the best SSVEP response quality and visual comfort. Finally, since there is no unified measuring method for visual comfort and a lack of differentiation in the high-frequency band, we proposed a measuring method and a division of the band. In summary, the review highlights which stimulus properties are important to consider when designing SSVEP BCIs. It can be used as a reference point for future research in BCI, as it will help researchers to optimize the design of their SSVEP stimuli. Full article