cancel
Showing results for 
Search instead for 
Did you mean: 

Virtual Reality Motion Sickness VR Simulator Illness Guide

OculusOptician
Explorer
*UPDATED AND REVISED OCT 10, 2014* APPLIES TO DK1 & DK2

Motion sickness while in Virtual Reality is correctly known as VR Sickness, Cyber Sickness and Simulator Sickness. Users who begin to experience VR Sickness while using the Rift should limit their usage times to around 10 minute intervals in order to build a tolerance against it and consider the guide below. Don't try and fight symptoms as conditions will only persist and you can literally get to the point of vomiting. Keep in mind, VR Sickness is not a serious problem and there are methods in reducing and completely removing it from Virtual Reality experiences mentioned further below.

Originally, OculusVR knew very little about simulator sickness (VR sickness), however they have made great strides regarding the problem over the past few years.

Since 2012 I have been actively researching this topic and seem to be more versed than the United States Army and even NASA at this point after frequent reading of their past reports on the subject which are obsolete and out of date at this time. As such, I was required to hire a vestibular specialist who proved very valuable in solving more complex concerns and answering specific questions that were raised. Below is a summary of what I learned over the last couple years.

Early methods of correcting simulator sickness have been developed by NASA due to frequent reports of astronauts showing symptoms in space and during simulator testing. NASA's solution was to introduce a pair of electronic shutter glasses flashing at a specific frequency and dwell time. These systems are not very effective. The US Army conducted a costly and extensive report back in 2005 regarding simulator sickness. The consensus of the report didn't specify any solutions to the problem, only statistical findings.

Motion sickness is the direct opposite of simulator sickness however they both feature nearly identical symptoms with the exception that Motion sickness is known in creating a sense of post movement afterwards whereas cyber sickness typically leaves a feeling of dizziness as a result. Shared main symptoms by order include nausea followed by vomiting, dizziness, reduced spatial awareness, sopite syndrome (exhaustion), increase in appetite and frequent bowel movements.

The cause of these symptoms is due for two reasons. First, the brain receives conflicting cues namely from the visual cortex, posture and vestibular system and secondly from erroneous data that's processed from the users perceptual system as a result. The reason for these symptoms are to protect the body from a false positive of neurotoxins which the brain believes the user has ingested or absorbed based on conflicting processed data from the perceptual, vestibular, postural and visual system.

Susceptibility to simulator sickness is a complete random occurrence in individuals. Gender and race make no difference with the exception of the Asian population. Asian's statistically are reported to have elevated motion and VR sickness related issues. A popular household remedy in Asia is rub eucalypti leaves together and inhale the scent produced from them. Resistance training for sensitive individuals is very effective. It's one of the most effective methods for significantly reducing to completely eliminating symptoms. Around 5% of all individuals will never acclimate regardless how much they try to build a resistance to it meaning there is a confirmed minority of individuals who will never be able to us Virtual Reality as a mainstream product over their lifetime.

Surgical methods have been considered in the past for corrective treatment options however they are only used as a last ditch effort to correct patients with severe balance and vestibular issues. Chemical injections are almost always utilized in these cases and the majority of patients who undergo injections usually go deaf from the surgery as a result since the vestibular system is linked directly to the hearing system. Interestingly enough, deaf people don't suffer from any forms of motion sickness and likely simulator sickness as well.

PROVEN METHODS FOR CORRECTING VR SICKNESS

- Utilizing a software process called Comfort Mode developed by Cloudhead Games.
- Utilizing the Comfort Mode 2 I developed which considerably reduces VR Sickness and significant GPU throughput at the same while still maintaining a great experience. Is fully compatible with Comfort Mode 1.
(PM me for details)

- Positional tracking and experiences which don't create vestibular conflict such as sitting or standing on the spot. For all other walking, running and motion experiences, Omni directional treadmills and 6DOF rigs can substantially reduce vestibular conflict as well.
- Properly calibrate the developer kit to your specific eye settings. Everyone has different eye measurements and these include pupil distance, distance from your eyes to the screen (field of view) and lens center (distance from the actual center of the lenses). This needs to be calibrated in the game and it's the number one contributor to motion sickness if not tailored to suit your personal requirements
- Make sure that you deal with any additional visual issues relating to prescription eye wear and adjust in software if necessary. If your IPD is off, check out IPD adjusters by VR Gear at http://www.vr-gear.com
- Maintain lowest latencies and accurate head tracking possible within hardware. Nvidia 9 series graphics cards feature additional features on improving this.
- Run higher resolutions
- Maintain Focal depth (it's controversial whether this actually helps for the moment)
- Reducing the field of view below 30 degrees stops VR sickness completely however it's not a viable solution. The higher the FOV past 30 degrees VR sickness incrementally gets worse.
- Random shapes and sizes are more preferred as opposed to staight and jagged lines.
- Play more slowly, turn your brightness level down on the rift control module and turn the volume down. This makes a big difference.
- Eat or drink food products containing ginger. This really helps reduce nausea. Don't rely on this however as it doesn't treat any other symptoms associated with cyber sickness besides feeling nauseous.

REASONS THIS WAS MORE OF AN ISSUE IN THE PAST & A BRIEF HISTORY LESSON

- 3D Games weren't actually just that back in the day, they just appeared to be. A good example of this is Duke Nukem 3D which against common belief wasn't actually 3D. It was actually a cleaver representation of a 3D environment. Ken Silverman created a very effective engine that utilized this false imagery and people could get sick just playing his games on their monitor. A game he wrote called Ken's Labyrinth was the perfect candidate for brutal motion sickness even while playing from a standard display. Doom was also another VR compatible game that caused serious motion sickness issues with and without a VR headset. Dwayne "The Rock" Johnson actually got motion sickness the first time he played doom on the computer back in the day.

- Latency and frame rates were much worse back then. This makes a huge difference influencing motion sickness.

- The 3D dual image setups were not as accurate in the past. Again this makes a large difference regarding motion sickness.

- Head tracking wasn't as accurate and calibrations were likely not as accurate either. If the motion calibration is not 100% precise, our brains will subconsciously conflict what we are used to in the real world. Also if the tracker isn't accurate enough, this further enhances the problem. OculusVR actually built a temperature controlled room with a 100% level test bench for testing their exclusive motion system during development to ensure their system was as accurate as possible for developer kits. This in turn will significantly help users combat motion sickness.

- Graphics were not as representative to what we have today, poor resolution and motion blur was more of an issue as well. This actually has an effect and has only been improved. While game graphics, even for today's standards are still not perfect and motion blur still plays a role on HMD devices, these are mainly the only remaining issues that can cause motion sickness for Rift users. As game graphics are improved and made more accurate, resolution is improved and refresh rates in the actual screen are reduced, this will significantly improve over time.

- Positional tracking didn't exist.

HOW DEVELOPERS CAN REDUCE MOTION SICKNESS FURTHER

- Make sure the 3D rendering and shaders are setup perfectly. Provide an option for users to access full adjustment of their eye configurations. Everything has to be optically correct.

- Make in game motions as close as possible to 1:1. Slow walking speeds, a sense of jumping and awareness need to be consistent with how we experience the real world, this one is pretty obvious.

- Make games where a fixed reference point can be observed in the game world. For example a cockpit that makes the gamer feel they are inside an actual vehicle. Provide some form of solid reference in the game that gamers can focus on and to mentally understand their surroundings.

- Use darker textures, this claims to make an improvement for many users.

- Don't use repeated patterns, like checker board or strips and lines. Make natural dark textures that flow with nature.

- Use a proper sense of scale. If you feel really small in the game world, the ground will move even faster below you and this also sends conflicting messages to the brain.
34 REPLIES 34

raidho36
Explorer
I don't suffer VR sickness whatsoever and I never was so I can't really contribute anything, shame.

But to some degree, certain things make my VR experience uncomfortable. Namely, low framerate and headtracking lag. But that's not new, too, I just happen to suffer from it to a far lesser degree than most people.

rc
Honored Guest
"leftbigtoe" wrote:
Still I wanted to share the upshot of a conversation I had with an aspiring jet fighter pilot recently. He told me that some of the pilots have massive problems with air sickness which is somewhat related to motion sickness. He told me, they have a special program for pilots to help them cope with it, having a success rate of around 80% tho overcome airsickness. Interestingly, one of the major points of the program is to help the pilots deal with stress. Those guys are overwhelmed with a crazy amount of stuff to do in parallel and apparently this stress somehow makes them more prone to motion sickness. I would be interested if that matches somewhat with your observations. Could that be one the reasons why repeated exposure helps...not only because your perception learns to deal with the mismatch but also because you become more relaxed since you already know the game? This could also explain why playing the game on a monitor beforehand might help. You know the game mechanics and the interface, so more cognitive load is free to deal with the VR experience itself.


Very good point. I noticed that the Oculus guys, when demoing it to people, would try to ease them into the VR experience slowly. Have them sit down, put on the HMD first, get used to that, then introduce controls and later the headphones.

It'd probably be a good idea to make sure your game has a 'new-to-VR' setting that starts off very simplified and slow, and then ramps up features and movement speed gradually if the player is comfortable with it. Like the tutorials or prologues that are often integrated at the beginning of many games, but I think it'll need to be to a much greater extent with a VR game.

Perhaps the Oculus should have it's own acclimatisation program as well?

KWUEST
Honored Guest
I have just got the DK2 and have not used the DK1.

When first testing the VR experience (after calibrating he HMD for my physiology) I tried the Unity made for the rift and direct to HMD demo game "Cyberspace" ride. Even though quite extreme movement in the game, because it was a short experience and designed with a few good basics, I did not fee much motion sickness. Just the ideal sensation of what the demo is trying to convey, but without that sickly feeling.

I tried the DK2 Half-life Beta which at the time needed lots of tweaks to get it working, obviously not ready yet. One of my all time favourite immersive games, it was amazing to see the characters "in the world". But (to the point):

The implementation of some of the design (at this current stage) and after about 20-30mins of playing I got extreme motion sickness, to the point where the next day, seeing the 2d mirrored image on screen (cyberspace demo) while someone else was using it, brough back on the motion sickness from the previous day, without even wearing the HMD! Like some kind of Pavlovian response.

The bad elements of the HL2 games implementation I can attribute it to:
** Freeze frame loading screens - in between scenes (the way HL2 does it) - wow super sinking sickness feeling!
** A dead zone in the middle of the screen where the mouse aim and head movement interact.
** Strafing, did not seem that bad for me, but seems to add to it.
** Sense of size a bit off and not being able to see your own body.
** Hard to read UI

I was really enjoying the game immersion experience but at the same time wanted to continue against waves of sickness that were hitting me. I should have got out a bit earlier.

This is all essentially a UX (User eXperience) issue and I see that developing games/experiences is going to need very specific early analysis and best practice development for implementation of UX. UX methodology is going to be really important for the adoption of apps/games/experiences to a broader market (other than hard core adjusted gamers), for our developments to be successful and make money as part of a thriving marketplace.

The more UX is enforced and applied by the HMD SDK('s) and developer practices in a rigorous methodology, the faster the future of VR will come to everyone.

kzacharias
Honored Guest
"kingtut" wrote:
I've just created https://developer.oculus.com/wiki/index.php?title=Motion_Sickness to summarise the discussions. Obviously feel free to edit.

Note that discussions etc should definitely take place on the forums, but I think the wiki is a better way to collect and collate the different threads which can and will pop up on this subject.


where did this thread go?
I can't find it anymore...

OculusOptician
Explorer
Just updated this guide, lot's of new critical info added.

tyhuber
Honored Guest
"OculusOptician" wrote:
Just updated this guide, lot's of new critical info added.



Do you mean the original post of this thread or this guide?. If it's the wiki, I'm getting a file not found error, just thought I'd let you know as this seems like a good resource.

OculusOptician
Explorer
Updated the original post at the beginning of this thread. I believe that Wiki section was taken down by Oculus. Have been working on this well before the best practice guide was even released.

OculusOptician
Explorer
I have a Comfort Mode 2 which really makes a difference in controlling nausea, it works separately or in conjunction with Comfort Mode 1. Any devs interested in applying it to their existing games please PM me for more info.

Anonymous
Not applicable
Great information, thanks OculusOptician. My educational background is in aviation (both theory and some flying) so it's interesting to read how much of the motion sickness research is mirrored in VR issues.

darthwilson
Honored Guest
Apologies for bumping this. I was actually about to post your GDC presentation but then I found this. Thanks for covering the topic, it was really helpful and opened my mind up to all the crazy possibilities! (y)