# Manipulating Underfoot Tactile Perceptions of Flooring Materials in Augmented Virtuality  
[PERSON]  
1 School of Product Design, University of Canterbury, Christchurch 8041, New Zealand; [EMAIL_ADDRESS] (J.T. ); [EMAIL_ADDRESS] (E.C. ); [EMAIL_ADDRESS] (T.P.) [PERSON]  
2 HIT Lab NZ, University of Canterbury, Christchurch 8041, New Zealand2  
[PERSON]  
1 School of Product Design, University of Canterbury, Christchurch 8041, New Zealand; [EMAIL_ADDRESS] (J.T. ); [EMAIL_ADDRESS] (E.C. ); [EMAIL_ADDRESS] (T.P)  
[PERSON]  
1 School of Product Design, University of Canterbury, Christchurch 8041, New Zealand; [EMAIL_ADDRESS] (J.T. ); [EMAIL_ADDRESS] (E.C. ); [EMAIL_ADDRESS] (T.P)  
Footnote 1: [[https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci)]([https://www.mdpi.com/journal/applsci](https://www.mdpi.com/journal/applsci))  
Footnote 2: [[https://www.mdpi.com/](https://www.mdpi.com/)]([https://www.mdpi.com/](https://www.mdpi.com/))  
visual appearance. Work by [PERSON] et al. [17] and [PERSON] et al. [18] investigated how virtual deforming can influence softness perception by visually changing how much it deforms. Research has looked at simulating various tactile properties without considering fully how the visual input affects the perception [10; 19; 20; 21]. Previous research has shown that altering the visual appearance alters a persons' perception of a material; however, this change has not been quantified. By quantifying this change, a single physical material can simulate a range of materials by altering the visual appearance to change a persons' perception of the material. The level of visual augmentation varies from material to material; by quantifying this level, a better understanding of simulating materials would be gathered. Rather than simulating tactile properties using virtual textures, we focus on how the tactile properties can be impacted by altering the virtual textures. We aim to explore how the tactile properties of roughness, hardness, and stiffness are impacted when the visual appearance of a material is altered. We focus on underfoot tactile experiences due to the lack of research in this area and the richness of the tactile experiences that are still available. To achieve this, we use indoor flooring materials as proxy objects. A user study consisting of two experiments was conducted to explore this further. In this study, participants experienced tactile feedback of flooring materials under various virtual visual appearances to determine how the augmentation influences their tactile perception. This research aims to provide insight into how visual feedback can be controlled to impact how haptic feedback is perceived. The first experiment explored how participants' perception of tactile properties--namely, roughness, hardness, and stiffness--was affected when the visual feedback was altered. We hypothesise that altering the visual appearance of materials will affect a person's tactile perception of the material **[H1]**. We also hypothesise that altering the visual appearance of materials with extreme tactile properties will have a less significant impact on tactile perception **[H2]**. The second experiment explored how aware participants were of the tactile feedback based on the given visual feedback when focused on another task. For this, we hypothesise that the use of virtual appearances that match the various physical materials will increase participants' awareness of tactile feedback **[H3]**. The findings from our study are intended to open further research into feet-based haptics and simulating a range of materials by changing visual appearances. Our contributions include the following:  
* An Augmented Virtuality system was devised to facilitate feet-centric interactions with virtual textures, mimicking indoor flooring materials. * Two perceptual experiments were conducted to investigate the influence of visual augmentation to flooring materials on an individual's underfoot tactile perception.