This paper investigates how sinusoidal terrain characteristics and input modalities influence locomotion performance and user experience in virtual reality (VR). Two studies were conducted using a custom-built elastic balance board (EBB). The first study (Study 1) employed a 2 (amplitude: low vs. high) × 2 (frequency: low vs. high) within-group (N = 24) design to examine how slope characteristics affect locomotion efficiency (i.e., speed and completion time), postural stability (i.e., sway velocity), and subjective experiences (i.e., motion sickness, vection, usability, fear of movement, presence, and workload). High frequency slopes in terrains increased completion time, sway velocity, motion sickness, fear of movement, and vection, whereas amplitude alone had minimal effects. The second study (Study 2) used a 2 (amplitude: low vs. high) × 2 (input: EBB vs. joystick) within-group (N = 25) design to explore amplitude effects further and compare locomotion input methods. High amplitude increased completion time, sway velocity, and fear of movement, while EBB use enhanced presence and vection but required a higher workload compared to joystick input. Across both studies, frequency emerged as the primary factor influencing locomotion demands, and amplitude effects became more pronounced when combined with embodied locomotion interfaces. These findings provide design guidelines for VR locomotion systems, emphasizing the importance of aligning terrain complexity with input modality to optimize user comfort and control accuracy.

Locomotion in virtual reality (VR) significantly impacts user immersion, spatial orientation, and overall experience. While traditional methods such as joystick-based movement and teleportation remain common, they present challenges like spatial disorientation, reduced presence, and motion sickness. In contrast, more embodied techniques, such as walking-in-place (WIP) and balance boards, aim to provide a more naturalistic form of locomotion. However, balance boards have proven to enhance the sense of control and presence in VR environments. Thus, we decided to further explore the benefits of isometric and elastic balance boards by examining their effects on VR locomotion movement behaviors, user experience, and motion sickness symptoms during a path-following task. We followed a 2 (feedback: isometric vs. elastic)$\times 3$(orientation: virtual vs. physical vs. conditional virtual) within-group experimental design involving 28 participants. The collected data included movement metrics (i.e., trajectory length, speed, time, root mean square error, sway velocity), user experience metrics (i.e., usability, spatial presence, task load, intrinsic motivation), and motion sickness metrics. Our results indicated that orientation significantly affected trajectory length, speed, and sway velocity, while feedback strongly influenced movement accuracy. Additionally, the user experience was influenced by the combination of feedback and orientation, with participants favoring elastic feedback, particularly when paired with virtual orientation. Finally, we found motion sickness to be less pronounced with elastic feedback, especially in virtual and conditional virtual orientations, highlighting the importance of feedback in reducing discomfort during VR locomotion.

We explored how study participants interacted with virtual characters in a virtual reality study. Specifically, we developed a 3 (proximity: close vs. middle vs. far) $\times 2$ (gesture: passive vs. active) experimental design (N = 26) to understand how combinations of proximity between two virtual characters and gestures assigned to them influence study participants’ self-reported ratings (co-presence, attentional allocation, behavioral interdependence, emotional reactivity, and perceived politeness). We also examined their avoidance movements (duration, trajectory length, and speed) and their avoidance decisions (passing through/around and minimum distance side). We collected both survey responses and our participants’ trajectories. Our study revealed that 1) the proximity factor impacted how our participants rated their co-presence and behavioral interdependence, as well as whether they decided to pass through or around the virtual characters, and 2) the gesture factor impacted how participants rated their behavioral interdependence, emotional reactivity, perceived politeness, and also affected their duration, trajectory length, and speed. Our research contributes to understanding personal space and social norms in virtual environments, offering valuable insights for virtual reality developers on the importance of social dynamics in designing interactions with virtual characters.

We explored the avoidance movement behaviors of study participants immersed in a virtual reality environment. We placed a static virtual character at the midpoint between the start and target spot for the avoidance task, and a virtual walker character in front of the starting spot and scripted it to reach the target spot. Participants were placed behind the virtual walker in order to measure its influence on participants’ behavior. We developed nine experimental conditions assigned to the virtual walker character by following a 3 (speed: slow vs. normal vs. fast walking speed) $\times 3$ (proximity: close vs. middle vs. far proximity to the static virtual character) study design. For this within-group study, we collected data from 22 study participants to explore how speed and proximity walking patterns assigned to a virtual walker character could impact participants’ avoidance movement behaviors and decisions. Our data revealed that 1) the speed factor impacted the participants’ avoidance movement behavior; 2) the proximity factor did not significantly impact the participants’ avoidance movement behavior; 3) the virtual walker character did not significantly impact participants’ avoidance decisions regarding the static virtual character; 4) in all examined conditions, the side-by-side distances between the participants and the static virtual character were inside the social space according to the proxemics model; and 5) in conditions in which a slow virtual walker character was present or in the condition of normal speed and far proximity, we observed an increased number of participants pass the virtual walker character.

Abstract We investigated the movement behavior of participants walking within a virtual crowd in an immersive virtual environment. We investigated three different parameters that characterize a moving virtual crowd: density, speed, and direction. An immersive road‐crossing scenario that took place in a virtual metropolitan city was created. In this scenario, the participants were instructed to walk toward the opposite sidewalk. Three measurements (speed, deviation, and trajectory length) were used to evaluate the impact of the parameters assigned to the virtual crowd on the movement behavior of the participants. Significant results were found for both the main and interaction effects. The results suggested that the high density, low speed, and diagonal direction situations associated with the virtual crowd had the greatest impacts on the speed, deviation, and trajectory lengths of participants when they walked in a virtual environment and were surrounded by a moving virtual population.