Cross-platform virtual environments allow users to experience interactive virtual places from a variety of peripherals, such as mobiles, computers or virtual reality headsets. These devices offer different interactivity and immersion levels, which shape the subjective experience of presence in the virtual space. Moreover, users may be provided with virtual representations, or avatars, to evolve in the environment. Controlling such avatars will likely induce a sense of embodiment and an identification toward these representations. When using cross-platform applications, users may have to transpose their experience across different devices, likely transporting their avatar and prior experience with them. In this context, understanding the impact of device transitions and prior experience may have over user experience constructs appears critical. We designed an experiment to explore their effects, which primarily unveiled that transitioning from high-immersion devices to low-immersion ones causes a significant drop in users' sense of presence, embodiment and identification. These results are supposedly due to a comparison effect between devices emphasized by the strong expectations created by the first exposure in VR. Our study further unveiled a strong connection between the sense of embodiment and character identification demonstrated by statistical correlations. It finally confirmed that identification may persist across devices and exposures, shedding light on this avatar-related construct for research on cross-device realities.

Embodied representations are known to influence user behavior in virtual environments through stereotypes associated with their appearance, a phenomenon known as the Proteus effect, or through perceived affordances. The latter concept refers to the suggested ways of interacting with the environment as perceived by the capabilities of the user's virtual representation. The inherent ability of virtual reality to support non-anthropomorphic avatars, enabling new interaction modalities, paves the way for a deeper understanding of affordances in virtual environments. We designed an experiment to assess the effect of embodying a chimeric hand (crab claw), compared to a regular hand, on participants' sense of embodiment, presence, character plausibility, mental workload, and behavior. Following a within-subject design, participants took part in a gamified task consisting of finding a key in a wrecked pirate ship. As the key could be hidden in containers of different durability, their strategy (opening or destroying objects) was used as an objective measure. Results indicated a high perceived usability and a low mental workload with both virtual limbs. Participants also performed hitting actions more frequently when using the biomimetic limb than when using the humanoid hand representation. A higher perceived change in the body schema was reported when embodying the crab claw, but a higher sense of body ownership and agency were observed with the anthropomorphic hand. Results revealed no significant difference in terms of plausibility.

The way users interact with Virtual Reality (VR) environments plays a crucial role in shaping their experience when embodying an avatar. How avatars are perceived by users significantly influences their behavior based on stereotypes, a phenomenon known as the Proteus effect. The psychological concept of affordances may also appear relevant when it comes to interact through avatars and is yet underexplored. Indeed, understanding how virtual representations suggest possibilities for action has attracted considerable attention in the human-computer interaction community, but only few studies clearly address the use of affordances. Of particular interest is the fact aesthetic features of avatars may signify false affordances, conflicting with users' expectations and impacting perceived plausibility of the depicted situations. Recent models of congruence and plausibility suggest altering the latter may result in unexpected consequences on other qualia like presence and embodiment. The proposed research initially aimed at exploring the operationalization of affordances as a tool to investigate the impact of congruence and plausibility manipulations on the sense of embodiment. In spite of a long and careful endeavor materialized by a preliminary assessment and two user studies, it appears our participants were primed by other internal processes that took precedence over the perception of the affordances we selected. However, we unexpectedly manipulated the internal congruence following repeated exposures (mixed design), causing a rupture in plausibility and significantly lowering scores of embodiment and task performance. The present research then constitutes a direct proof of a relationship between a break in plausibility and a break in embodiment.

Future crewed missions to the Moon will face significant environmental and operational challenges, posing risks to the safety and performance of astronauts navigating its inhospitable surface. Whilst head-up displays (HUDs) have proven effective in providing intuitive navigational support on Earth, the design of novel human-spaceflight solutions typically relies on costly and time-consuming analogue deployments, leaving the potential use of lunar HUDs largely under-explored. This paper explores an alternative approach by simulating navigational HUD concepts in a high-fidelity Virtual Reality (VR) representation of the lunar environment. In evaluating these concepts with astronauts and other aerospace experts (n=25), our mixed methods study demonstrates the efficacy of simulated analogues in facilitating rapid design assessments of early-stage HUD solutions. We illustrate this by elaborating key design challenges and guidelines for future lunar HUDs. In reflecting on the limitations of our approach, we propose directions for future design exploration of human-machine interfaces for the Moon.

Space agencies are in the process of drawing up carefully thought-out Concepts of Operations (ConOps) for future human missions on the Moon. These are typically assessed and validated through costly and logistically demanding analogue field studies. While interactive simulations in Virtual Reality (VR) offer a comparatively cost-effective alternative, they have faced criticism for lacking the fidelity of real-world deployments. This paper explores the applicability of passive haptic interfaces in bridging the gap between simulated and real-world ConOps assessments. Leveraging passive haptic props (equipment mockup and astronaut gloves), we virtually recreated the Apollo 12 mission procedure and assessed it with experienced astronauts and other space experts. Quantitative and qualitative findings indicate that haptics increased presence and embodiment, thus improving perceived simulation fidelity and validity of user reflections. We conclude by discussing the potential role of passive haptic modalities in facilitating early-stage ConOps assessments for human endeavours on the Moon and beyond.

Revived interest in lunar exploration is heralding a new generation of design solutions in support of human operations on the Moon. While space system design has traditionally been guided by prototype deployments in analogue studies, the resource-intensive nature of this approach has largely precluded application of proficient user-centered design (UCD) methods from human-computer interaction (HCI). This paper explores possible use of Virtual Reality (VR) to simulate analogue studies in lab settings and thereby bring to bear UCD in this otherwise engineering-dominated field. Drawing on the ongoing development of the European Large Logistics Lander, we have recreated a prospective lunar operational scenario in VR and evaluated it with a group of astronauts and space experts (n=20). Our qualitative findings demonstrate the efficacy of VR in facilitating UCD, enabling efficient contextual inquiries and improving project team coordination. We conclude by proposing future directions to further exploit VR in lunar systems design.

Revived interest in lunar and planetary exploration is heralding a new era for human spaceflight, characterized by frequent strain on astronaut’s mental well-being, which stems from increased exposure to isolated, confined, and extreme (ICE) conditions. Whilst Immersive Virtual Reality (IVR) has been employed to facilitate self-help interventions to mitigate challenges caused by isolated environments in several domains, its applicability in support of future space expeditions remains largely unexplored. To address this limitation, we administered the use of distinct IVR environments to crew members $(n=5)$ partaking in a simulated lunar habitat study. Utilizing a Bayesian approach to scrutinize small group data, we discovered a significant relationship between IVR usage and a reduction in perceived stress-related symptoms, particularly those associated with asthenia (syndrome often linked to chronic fatigue and weakness; a condition characterized by feelings of energy depletion or exhaustion that can be amplified in ICE conditions). The reductions were most prominent with the use of interactive virtual environments. The ’Aesthetic Realities’ - virtual environments conceived as art exhibits - received exceptional praise from our participants. These environments mark a fascinating convergence of art and science, holding promise to mitigate effects related to isolation in spaceflight training and beyond