A Preliminary Study on Full-Body Haptic Stimulation on Modulating Self-motion Perception in Virtual Reality

Abstract

We introduce a novel experimental system to explore the role of vibrotactile haptic feedback in Virtual Reality (VR) to induce the self-motion illusion. Self-motion (also called vection) has been mostly studied through visual and auditory stimuli and a little is known how the illusion can be modulated by the addition of vibrotactile feedback. Our study focuses on whole-body haptic feedback in which the vibration is dynamically generated from the sound signal of the Virtual Environment (VE). We performed a preliminary study and found that audio and haptic modalities generally increase the intensity of vection over a visual only stimulus. We observe higher ratings of self-motion intensity when the vibrotactile stimulus is added to the virtual scene. We also analyzed data obtained with the igroup presence questionnaire (IPQ) which shows that haptic feedback has a general positive effect of presence in the virtual environment and a qualitative survey that revealed interesting and often overlooked aspects such as the implications of using a joystick to collect data in perception studies and in the concept of vection in relation to people's experience and cognitive interpretation of self-motion.

A Systematic Review and Meta-Analysis on The Use of Tactile Stimulation in Vection Research

“…In the 23 articles we found through our literature search, the application of tactile stimuli varied from applying forces to the body (Oishi et al, 2016), blowing wind (Churan et al, 2017;Feng et al, 2016;Seno, Ogawa, et al, 2011), stretching the skin (Horie et al, 2018) to vibro-tactile stimulation of various body parts. Vibro-tactile stimulation was applied to the buttocks (Amemiya et al, 2016(Amemiya et al, , 2013b(Amemiya et al, , 2013a, dorsal side of the body (Lind et al, 2016), feet (Kitazaki et al, 2019(Kitazaki et al, , 2016Kruijff et al, 2016;Matsuda et al, 2020;Nilsson et al, 2012;Nordahl et al, 2012;Väljamäe et al, 2009), the lower back and buttocks (Soave et al, 2020), torso (Rupert & Kolev, 2008) and waist (Tinga et al, 2018). Participants passively experienced the stimuli except in the experiments by Kruijff et al (2016) wherein participants controlled the movement of a virtual avatar by either leaning forward or by moving a joystick.…”

“…Participants were instructed to rate their perceived self-motion during the stimulus presentation by entering a numeric value using a keyboard, a pressing a button (Farkhatdinov et al, 2013;Seno, Ogawa, et al, 2011), moving a joystick (Riecke, Schulte-Pelkum, Caniard, et al, 2005;Soave et al, 2020), or via verbal reports (Horie et al, 2018;Väljamäe et al, 2006Väljamäe et al, , 2009. However, in some studies, participants rated the magnitude or intensity after the stimulus present by means of a questionnaire (Feng et al, 2016;Kitazaki et al, 2019Kitazaki et al, , 2016Lind et al, 2016;Matsuda et al, 2020;Oishi et al, 2016), verbal report (Kruijff et al, 2016;Nilsson et al, 2012;Nordahl et al, 2012;Riecke et al, 2009;Tinga et al, 2018) or by entering a value using a keyboard (Amemiya et al, 2016(Amemiya et al, , 2013b(Amemiya et al, , 2013aSeno, Ogawa, et al, 2011).…”

“…From the joystick position, the authors computed vection onset, duration, intensity, and build-up time. Similarly, Soave et al (2020) investigated whether their novel designed device could facilitate or enhance linear vection through vibrotactile stimulation produced by sound. Participants passively viewed the movement of the train from the firstperson perspective and used a joystick to rate the perceived intensity of vection during a trial.…”

“…The stimulation characteristics varied between the studies of Amemiya et al: Various patterns of tactile flow were achieved by subsequent activation of each row of the tactile stimulator with different delays or by subsequent activation of the same row to create a tapping sensation. Soave et al (2020). Right: Device used by Kruijff et al (2016).…”

“…Vibrational stimulation to the buttock area was also performed by Soave et al (2020) whose set-up, as shown in Figure 3, comprised of a chair equipped with eight Lofelt haptic actuators, which stimulated the area of the lower back as well. Similarly, Riecke et al (2009) applied tactile stimulation to the same areas by attaching a motor with an eccentric weight to the frame of a hammock chair that vibrated at 7Hz.…”