Virtual reality (VR) motion sickness, a common side effect of exploring VR worlds for many users, could be eradicated with a new system that dynamically changes the field of view (FOV).
This method of combating VR sickness is touted as being easily applied to existing consumer head-worn displays, such as the Oculus Rift, HTC Vive, Sony PlayStation VR, and Google Cardboard.
Developed by engineering professors Steven K Feiner and Ajoy Fernandes at Columbia University, the approach dynamically and subtly alters the user's FOV in response to visually perceived motion as they traverse an environment while remaining physically stationary.
While VR motion sickness effects people to different extents, in a study assessing the impact of the FOV system on participants, it was shown that it could drastically reduce its negative impacts for people who suffer from it while using VR platforms.
Furthermore, the researchers accomplished this without decreasing the participants' sense of presence in the virtual environment, and without the majority of them even being aware of the intervention.
"2016 is the year of VR and it's estimated that over 200 million VR headsets will be sold by 2020," said Feiner.
"But VR sickness, which has symptoms similar to motion sickness, poses a barrier for many users of this immersive technology. People who experience VR sickness will often stop using their headsets, as they feel nauseated and uncomfortable."
The approach changes the FOV in a way that many participants found imperceptible. "I was aware of work on change blindness--a concept in perceptual psychology that explains why people sometimes do not notice what would seem to be an obvious change in a scene," explains Fernandes, who himself has suffered from VR sickness. "So I wondered if this could be applied to VR: could we change a participant's FOV without them noticing?"
The team specifically targeted scenarios in which users move in the virtual environment in a way that intentionally differs from how they move in the real world.
These include games in which they are physically standing or sitting on a couch in their living room, while walking, running, driving, or flying in the virtual world.
In these scenarios, the visual motion cues that users see are at odds with the physical motion cues that they receive from their inner ears' vestibular system, the cues that provide us with our sense of motion, equilibrium, and spatial orientation. When the visual and vestibular cues conflict, users can feel quite uncomfortable, even nauseated.
In many cases, decreasing the field of view can decrease these symptoms. But decreasing FOV can also decrease the user's sense of presence in the virtual environment, making the experience less compelling.
So the system only subtly decreases the FOV in situations when a larger FOV would be likely to cause VR sickness and restores it when VR sickness is less likely to occur.
Software was developed that functions as a pair of ‘dynamic FOV restrictors’ and can partially obscure each eye's view with a virtual soft-edged cutout. It was then determined how much the user's field of view should be reduced, and the speed with which it should be reduced and then restored.
A multi-day user study divided 30 voluntary participants into two groups; one group explored a VR environment without the dynamic FOV restrictors on one day and with the restrictors on a second day with the order reversed for the second group.
When study participants used the FOV restrictors, they felt more comfortable and stayed in the virtual environment longer than they did without the restrictors. Two kinds of restrictors were used, one of which was designed to be more subtle than the other.
Most of the participants who used the more subtle restrictors did not notice them, and all those who did notice them said they would prefer to have them in future VR experiences.
"Virtual reality has the potential to profoundly change how we interact with people, machines, and information," Feiner said. "It is critical that the experience be both comfortable and compelling, and we think we've found a way."
Both Sony and Microsoft unveiled new versions of their respective consoles at E3 this week that contain more processing power than before in order to enable the platforms to support VR games and 4K resolutions.
Combating VR motion sickness - infographic