George Kong of Huge Robot recently released a video detailing his solution to VR locomotion. The demo he references in the video can be downloaded from here and I would highly advise checking it out when you get some time. The system seemed very compelling to me upon watching and I was eager to check it out. It was developed and designed for the Vive, so not everything works perfectly with the Rift, but the piece I was most interested in trying still works fine. It’s called CAOTS, a form of locomotion in where bobbing of your head translates to movement speed.
Also to note, I’d say I’m moderately susceptible to motion sickness, the most intense style I can handle is free movement with snap turning, sometimes even those can get to me if there happens to be a lot of vertical traversal in the level design.
Things That Worked
The system really seems to hit its sweet spot when you’re jogging or running. In fact, the way it incorporates your hands into the mix creates a very compelling sense of motion. There was a point in the demo where I was running along a zigzag pathway. I was at a decently fast jog pace, and actually felt a wave of presence hit me. My brain was totally fooled into thinking I was actually running along the path!
When this video first released, reddit user hotvrz smartly pointed out that the bobbing head movement scheme would be a detriment to moving smoothly and tactically in a game like Onward. I spent a fair amount of time sneaking around the town level and found that tactical movement was very doable. Steady movement can be obtained with a very slight motion of the head. Take this with a grain of salt though, it would be hard to say how much of an impact it would have until you actually implemented it in a highly competitive scenario like Onward.
Now this next point could be a bit of contention as to whether it’s a positive or negative, but using CAOTS definitely gets your heartrate up and breathing pace increases. For whatever reason, I’ve always thought fitness and video games would never be able to co-exist but in VR, the physicality contributes to the overall experience for first person games.
Things That Didn’t Work
While jogging and running are great, CAOTS struggles with the most basic of human movement, walking. When I tried to use a relaxed, gentle pace, my translated movement speed was way too slow to be useable. This is due to most of the motion being in my feet, not my head. So you end up using this jazzy jive movement and that’s about as close as you can get to walking. It’s not terrible, but it takes some getting used to and doesn’t feel totally natural or comfortable. Strange side note: I noticed myself timing my bounce pace with the in-game music and that was oddly satisfying.
Another downside is, because movement is dictated by your head moving up and down, if I were jogging through town and I suddenly crouched to take cover behind a car I would lunge forward in the game world. The same is true if you are crouching and jump up to a standing position, you’ll fly forward a good 10 yards or so. It also happens to a lesser extent when you suddenly look up or down while moving.
Another use case of incongruent real motion to game motion is when you come to a stop after running. My running pace has a more controlled bounce pattern to it, and as my legs relax and break to stop, the bounce becomes more aggressive. This results in odd sudden jerks forward. Conversely, if you release your movement button as you reach your destination, you will immediately stop with no period of deceleration. This is very jarring and usually leads to throwing off your balance.
After a couple different play sessions, I think overall, it does help fight motion sickness albeit probably not enough. My first play session was about 40 minutes long and I felt just a little bit woozy afterwards. That could be attributed to me simply adjusting to a new locomotion system though. My second play session I did much better. Going up and down steep inclines seemed noticeably less averse in particular.
My wife graciously agreed to try out the system as well. She has a more timid walking/running style and couldn’t get the system to really move as fast as she wanted.
What This Means For Locomotion Going Forward
The one thing this experience has driven home for me is that, if we want a more complete, natural feeling locomotion system in VR, we need to better understand what is going on with our feet. In the long term, I still think something like Telaria VR’s solution would be more natural and intuitive. But given the current state of VR hardware, this system does an admirable job and brings us closer to a more ideal locomotion system for first person games.
Thanks to Huge Robot for spending time and effort on this issue and sharing your results with the community; I can’t wait to see what games you create with it. Thanks to all for reading! Apologies for bad grammar, it tends to go out the window when I excitedly type. Let me know your impressions of CAOTS if you’ve given it a spin, and feel free to share thoughts on VR locomotion in general. 🙂