To prevent secondary disasters, remote-controlled construction machinery is being developed. However, traditional fixed-seat systems pose challenges such as reduced operability and simulator sickness. This study developed a remote-control system featuring a rotating seat, a camera-equipped radio-controlled construction machine, a head-mounted display, and a controller. During operation, the seat and the construction machine rotated synchronously. Experimental results indicated that operability, as assessed by the sense of agency, was significantly higher than zero only with seat rotation. Additionally, participants who experienced severe simulator sickness without seat rotation tended to show reduced symptoms with seat rotation, compared to those who experienced mild simulator sickness without it.

In virtual reality platforms, avatars featuring designs inspired by animal ears are widely used as self-expression and communication tools. In this study, we propose a tactile feedback method through hair movement linked with the avatar’s cat ears to generate a sense of ownership of virtual cat ears. We integrated shape-memory alloy soft actuators in the form of a tube into a head-mounted display and used them to move the hair, providing tactile stimulation. We conducted an experiment in which participants transformed into avatars with cat ears and scenarios where their heads were stroked. We investigated the impact of cat ear movement and tactile feedback linked to cat ears on the sense of ownership of the cat ears. The experiment’s results suggest that providing appropriate movements of cat ears and tactile feedback can induce a sense of ownership for cat ears that are not naturally present.

There is no shortage of examples of explanations that technology extends human functions, but they all share a common logic. This paper first seeks the origin of the idea of body extension by technology in Platonic philosophy, using “substitution” and “extension” as keywords. Next, by reconsidering the present from the discursive situation of the origin, the paper will scoop up issues that are neglected in today’s discussion of technology, especially those concerning the negative effects that technology can bring about, then point out an issue that is overlooked in both arguments concerning positive and negative effects, namely, the problem of how to discriminate these effects. Through clarifying the scope of the body extension philosophy derived from Plato, the paper aims to contribute to the philosophical consideration of technology and the steady development of body extension engineering.

Self-location is extended by splitting a virtual body to left and right, and inducing body ownership in that body. However, there is a limit in the range of self-location extension, as it has been shown that body ownership is weakened by splitting, and that body outside of the peripersonal space does not induce body ownership. In this study, we investigated whether using portals to complement body continuity generates body ownership in a distant split body and extends self-location. The results showed that body ownership decreased in the distant split body without portals, but was maintained in the condition with portals. However, self-location was not extended. The results suggest that portals can maintain body ownership in the distant body, but not extend self-location.

Recently, there has been a growing focus on wellbeing. However, what constitutes wellbeing varies from person to person. In a diverse society, it’s important for everyone to consider their own and others’ wellbeing and show mutual respect. The authors have developed a tool called “Cards for Collective Wellbeing” to facilitate awareness and sharing of values related to wellbeing. This paper reports an experiment comparing the effects of using the cards and free recall in a workshop in which participants identified their values and shared them with others, including the results of the effects on self-understanding and understanding of others.

It has been shown that there is an association between body movement image and sound, and recent studies have reported that increasing the frequency of sound for an ascending body movement (arm lifting movement) can emphasize the impression of lightness and speed of the movement. Since it has also been shown that left and right movements are emphasized by left-right sound images, we considered that the impression of the movement could be further emphasized by using the movement of up and down sound images in addition to the frequency. In this study, we examined the effect of using frequency changes in addition to the movement of the upper and lower sound images in the acoustic feedback accompanying hand movements in a two-dimensional plane. The experimental environment was a 4-channel loudspeaker arrangement consisting of a 2-channel stereo system and a 2-channel loudspeaker above. In the experiment, we combined the vertical and horizontal positional information with changes in the 4-channel sound image for a circular motion in the frontal plane, and then combined the movement of the sound image in the vertical direction with changes in frequency for an up-and-down arm motion. The results of the experiment showed that the motion of the up-and-down sound image without frequency change alone had no effect on the impression of the arm motion, but the combined presentation of up-and-down sound image motion and up-anddown frequency changed the impression of the lightness and speed of the arm motion. These results suggest that adding frequency changes to acoustic feedback in VR/AR and interfaces can enhance the impression of body motion.

Fish are widely kept around the world and said to bring stress-reducing and relaxation. Aquariums have long played an important role in the protection of fishes, research on their living, dissemination and enlightenment of knowledge, and entertainment. Though aquariums have introduced a variety of technology for the display to achieve these role, it is difficult to raise awareness of environmental issues occurring in distant oceans. In this study, we propose the use of technology of body ownership with the environment in which fish grow, and creating the feeling of symbiotic partner with fish to make users think of aquatic environment as an issue that affects themselves. By using body ownership techniques to make the aquarium and the space it contains, including the fish, become part of their own body, people become more interested in maintaining the space as a whole and, ultimately, an appropriate environment for the fish. The result shows that it is possible to induce a sense of body ownership with the fish tank, including the fish, by changing the shape of the fish tank and applying synchronous stimulation. The tendency was also confirmed that this method make the feeling that they are symbiotic partners.

In this study, we developed a system to create dance movements by augmenting body movements with a VR device to support dance creation. The system generates movements that partially differ from the user input by changing the body parts to which the input movements are applied and by processing and amplifying these movements. Six methods for creating dance movements were implemented with reference to the methods used in choreographic creation. Three choreographers were asked to try out the system and clarify the possibilities of creating dance movements in a virtual space. As a result, all three choreographers gave positive feedback about the usefulness of the system for creative work, but there were differences in the methods they found useful. Our findings indicate that the way choreographers explore movement using a VR system is not limited to a single approach but allows multiple possibilities. Even among this study’s three participants, each demonstrated a unique approach, such as being strongly aware of one’s real body, being immersed in the virtual body, and seeking an interaction between the real and virtual bodies.

In joint actions, the Social Simon Effect (SSE) manifests as a reaction time interference effect, triggered by the automatic activation of the co-actor’s behavior representations within the motor system. The relationship between the co-actor’s presence and their complementary actions has been explored. However, in virtual reality, as the avatar’s visual representation influences how others’ presence and actions are perceived, the occurrence of SSE may vary. This study examined the SSE in a virtual environment (VE) and looked into (1) whether the SSE can occur during joint actions of avatars in a VE; and (2) how the visual representation of the co-actor’s avatar affects SSE; through the joint Simon task performed by two adjacent virtual avatars. Based on these results, we discussed the potential relationship between avatar visual representation and social presence, perceived co-actor’s intentionality, and causality recognition of the co-actor’s behavior, as well as how these factors may facilitate or hinder the SSE.

Simultaneous presentation of category-mismatched visual and olfactory information with food changes the perceived flavor, but the effect of category-mismatched taste-olfactory information on the perceived flavor remains unclear. In this study, fish odor was presented during the ingestion of beef jerky using the Breath-Synchronized Olfactory Display, and the effects of category-mismatched taste and olfactory stimuli on perceived flavor were evaluated. As a result, the sensation of beef jerky was reduced with the breath-linking olfactory fish odor stimuli, and the sensation of dried squid was strongly perceived. The results suggest that the integrating category-mismatched taste and olfactory information changes the categorical perception of flavor.

Human scale perception is based on everyday experiences, making it difficult to imagine the world from the perspective of drastically different-sized beings like plankton or whales. However, virtual environments allow for exploration of worlds at various scales. While previous research has focused on replicating the sensation of altered body scales, there has been no clear method for seamlessly transitioning between different scale worlds while maintaining a natural sense of bodily transformation. In response, this study proposes a transition design that allows users to experience changes in body size while preserving the naturalness of their movements. This design aims to provide a sensation of “entering” into worlds of different scales, enhancing the immersive experience of scale transformation. We define this experience as “Transcale”.

In remote collaborative work, since collaborators are not in the same physical space, the referential scope of demonstrative pronouns used to indicate objects may differ between those who are local and those who are remote. However, the dynamics of such references in remote collaborative environments remain underexplored, particularly regarding how an user’s movement velocity influences the scope of these demonstrative indicator. Therefore, this study aims to clarify the referential scope and consensus areas of demonstrative indicators used by local and remote users for objects in a remote collaborative work scenario where both the local and remote users share the same perspective, particularly when the local user is in motion.

Redirection techniques decouple tracked physical motion from virtual motion, allowing for motion amplification. In this paper, we present an experiment to investigate the detection threshold for roll rotation gain. Seated participants actively tilted their upper bodies by five degrees in the roll direction. The results showed that virtual roll rotations could be amplified up to 5.8 times without being perceptible to the participants. The detection threshold was increased by visual stimuli that generated optical flow in the same direction as the VR space rotation.