-updated 5/19/2017-Research and Statistics about Flight Simulators & VR Environments show specific ages, genders, heights, racial origins and people with limited or no exposure to VR & flight simulators are prone to simulator sickness. I provide links to all my resources at the end of this article.I fall into most of the categories that official research shows would cause me to suffer from simulator sickness – yet I am able to enjoy VR Experiences very much!This article shares info about building immunity to simulator sickness and ends with my own personal experiences with it as a new VR Architect.
VR or Simulator Sickness Symptoms:
VR sickness can include brief or prolonged dizziness, nausea and being extremely tired. Have you ever experienced simulator sickness? How did you build up immunity to it?
VR & Simulator Sickness Causes:
Simulator sickness is created when our physical senses that deal with self-motion are not in agreement with each another. The human brain of many people still have not been exposed to Virtual Reality and Flight Simulators, so their brains have not yet learned how to process a VR environment.As expected, the learning process can be uncomfortable and even create sickness for some people. Research is showing people that are most prone to simulator sickness include:
- never experienced flight, flight simulators, VR experiences
- female
- under or over average heights
- 50 years of age or older
- asians
Experience with VR & Flight Simulators
The more experience and exposure to VR Environments and Flight Simulators that a person gains, the less they become susceptible to simulator / motion / vr sickness. I look at it like this:Our human brain is constantly learning how to process our life experiences. The more exposure we get to VR Environments and Flight Simulators, the more our brain learns how to process and adapt to experiences that are not matching up with what our physical bodies have become accustomed to (inner ear, visuals, physical senses).
Sensory Conflict: Refresh Rate
If the refresh rate of what we view on screen in VR is not matching what our human brain has learned to process – it can create sickness. The following refresh rates are recommended by Unity3D for software engineers creating VR Environments.
| VR Device | Refresh Rate |
|---|---|
| Gear VR | 60hz |
| Oculus CV1 | 90hz |
| Vive | 90hz |
Sensory Conflict: Resolution
If the animation and resolution is too low, sickness can occur as we move our head in the VR environment because the motion is not matching what our brain has learned to process during our lifetime so far. Unity3D documentation suggests software engineers create VR Environments with a minimum resolution for Oculus to be 2160 x 1200 resolution at 90hz. VR ready pc is required to provide resolution that will not cause motion sickness.
Sensory Conflict: Motion
If the VR environment visuals and vestibular stimuli are not making sense to our human brain, we can get sick. If our ear does not transmit movement – while our eyes show that we are jumping or running or flying in the VR environment – we can get sick.As a VR Architect, I do all I can to build and test my new environment navigation to ensure I am not creating simulator sickness. This is quite a challenge for those of us that have more exposure to VR environments because we are less prone to become sick from even the more extreme physics that might be in a VR environment.
Sensory Conflict: Height
Software engineers can setup the height for the VR Environment’s camera to be at an average height. Average height is not the same height as everyone though. People that are under or over 5’6″ tall might feel unsteady while in such an environment where they are suddenly experiencing the world as a much taller or shorter person than they are used to. So far all of the VR Environments I have developed, I set the camera height to be at 5’6″ and have not made time to create a solution where everyone can tweak the eye height that is most comfortable.
Sensory Conflict: Jokesters
We have all seen the videos online of jokesters that mess with their friends while they are wearing a VR headset. Just don’t go into VR environments if any jokesters are near you.
Postural Instability
Some scientists found that responding to unexpected visuals with poor posture is creating simulator sickness. Scientists predict sickness occurs after a person’s posture goes wacky (odd leaning, falling over, slumping…) while inside a VR Environment that has no sensory conflicts.
Personal Background with Flight & Motion:
I never experienced motion sickness nor simulator sickness in my life, even after daily testing my own weird experiments with VR development projects for about 5 months.
Personal Simulator Sickness Experience:
Then a few weeks ago in my 6th month of daily VR development work & testing, I decided to create an extremely bizarre VR Experience for Oculus I developed to satisfy my curiosity about physics. It looked & felt as if I was extremely tiny and being slammed (with no warning!) right into the concrete floor, the ceiling, the walls and various objects inside the VR Environment and I was fine during the testing & development phase for about 3 or more days. I worked all day and often late into the night with my experiments while still waking up early the next day to get right back to my experiments. I was having fun :PAbout the 4th or 5th night, I had my first dream that was very much like being in my VR Environment with the bizarre physics! I have extremely vivid dreams my whole life and I must say that having a dream that is trying to process the bizarre physics I created in my VR Environment is something I will probably never forget!
VR Experiences remind me of dreams because I am usually laying down, not moving while I dream and my visuals are not matching my inner ear regarding movement, flight, etc. I am flying in many of my dreams too. Now that I have more experience in VR Environments that are becoming more & more extreme from the physical world, my dreams ( my brain processing my daytime experiences ) are also processing more & more extreme physics regarding flying, navigating and visuals that do not match my life experience with the physical world.
About the 4th or 5th morning – I woke up and experienced simulator sickness for the first time in my life. I was actually sick for about two days with it too – Horrible!. It felt worse than the one time I had a severe ear infection long ago (dizziness, nausea, extremely tired) and it seemed to just feel more & more horrible on and on and on forever and ever and ever!Now I understand why some people have such a negative view of VR after they experience simulator sickness! The good news is that research is showing most anyone can overcome simulator sickness by continuing to expose themselves to what made them feel ill in VR Environments or just avoiding the most extreme physics & movement in VR Environments.I can understand why many hesitate to go near VR after a bout of simulator sickness now that I’ve experienced it myself. I have been doing much shorter doses of exposure to my most extreme VR experiments and have not experienced simulator sickness again. I suspect I will experience it again when my curiosity to build something I’ve never seen before hits me again, but the benefits outweigh the brief illness because I have never heard of simulator sickness being deadly.
References:
Reason, J. T.; Brand, J. J. (1975). Motion sickness. London: Academic Press.Recommended Refresh Rates for Virtual Reality ,Unity3DRecommended Resolution for Virtual Reality ,Unity 3DVestibular Stimuli, WikipediaVirtual Reality Sickness,Wikipedia