Designing around Motion Sickness in VR
When I was designing iteractions for a Virtual Reality app, I was confronted with the infamous motion sickness. Motion sickness in VR is extremely common amongst new users, and since we are catering to such users, we need to address the issue and cause of such.
Virtual Reality Motion Sickness (VRMS)
Let us understand VR motion sickness in order to know how to counter it, VRMS (VR motion sickness) happens when your brain receives conflicting signals about movement in the environment around you, and your body’s relation to it.
In VR, this essentially means that if you are standing still and the virtual environment around you is moving, you disturb the brain’s equilibrium and you start to feel nauseous.
- As a result any forced movement can’t be added to the experience. It will not be comfortable force the movement of the user through 3D space.
Virtual Reality due to still being in its teenage years, there are a plethora of other symptoms. Many of them are due to the nature of the HMD (Head mounted display) making long sessions of use tiering on the eye. But for the experience we were working on we didn’t expect the user to be using the headset for more than 15min and as a result we didn’t address those other symptoms.
There are two good ways of addressing VRMS, making sure the experience is 6-DoF (6 degrees of freedom), making sure that we enable users greater freedom of movement within the virtual environment, and the environment around them, this will enable the users to adjust accordingly. This reduces the feeling of disorientation by providing you a better sense of presence and minimising those conflicting signals being sent to your brain that cause motion sickness.
Another way of dealing with motion sickness is through vignette. It is commonly used in apps and experiences that use joystick based locomotion. An in depth guide on all the types of locomotions used in Virtual Reality are explained here.
The vignette is proportionate to the speed of travel, the more abrut the changes of directions and acceleration are, the stronger the vignette effect is.
The seemless and proportionate response to movment enables to slightly eleviate VRMS, as it limits your FOV, focusing the user’s viewport to what’s infront of him and getting blurring/darkening the peripherial vision making head movment more fluide and less jerky feeling.
Fluidity is key when dealing with motion sickness. In short: bad framerate will not only be a strain on your eyes but will make you sick ! Large hardware manufacturer are aware of that and are now shipping HMDs with high refresh rates displays, the quest 2’s recently unlocking the120hz capability of their headset displays.
On the software side of things, apps must be extremely well optimized in order to keep the frames as high as possible.
My solution:
Despite those high frames, refresh rate and the vignette effects VRMS is still prevalent amongts many users. Therefore that is why I propose a out of the box solution. A way to remove VRMS would be to replace the vignette dark effect with the occulus quest’s guardian passthrough system (0.43). This would enable the brain to be remided of his place in the physical world and getting those pesky aforementionned mixed signals.
Although, I have yet to make a workable protoype in order to test such solution bridging the gap between VR and AR might the way forward to ease new users into the adoption of HMD.
Conclusion:
In order for the technology to be adopted by many it needs to be welcoming to new users, while progress is being made on the technology the HMD still need to be reduced in size and weight, and in order to eliminate the VRMS the experience needs to be as smooth as possible.
