VR Locomotion Is A Problem That Has Many Half-Solutions

Locomotion is one of the most glaring problems plaguing developers who work on VR games. In traditional video games, movement mechanics are pretty much locked down: You either have a keyboard and mouse or a gamepad. In the case of the former, you’ll use the arrow keys or the WASD keys to move forward and aft and strafe from side to side. In modern games, you make use of the mouse for aiming, targeting, or navigating menu items. Gamepads come with consoles, so developers always have a standard control scheme to work with that doesn’t change much from game to game.

You won’t find many VR-supported games that use keyboard and mouse configurations, but there are many VR games that take advantage of traditional gamepads. There’s nothing stopping developers from supporting the classic two-thumbstick artificial locomotion method that almost every first-person console game relies on, and in fact, some games do support that method. For example, Adr1ft offers the traditional control method, but that game is also playable on a 2D screen. Had the developer built the game for VR only, it may have chosen a different locomotion method. Most built-for-VR games shy away from linear lateral movement to maximize the audience that is comfortable playing it.

In VR, the concept of standard locomotion controls is turned on its head. Most of the time, traditional game controls don’t work well in virtual reality games. Lateral movement with a thumbstick or a keyboard can trigger motion sickness in a lot of people. Your inner ear controls your sense of balance and spatial awareness (vestibular system), if what your inner ear perceives is different from what your eyes perceive (vestibular mismatch) you can lose your balance or get dizzy. A vestibular mismatch can even trigger nausea or vomiting in extreme cases.

Vestibular mismatch problems became apparent in the early days of Oculus VR development. VR developers quickly discovered what triggers motion sickness, and several devs started working on solutions for the problem. So far, we’ve encountered no less than a half-dozen different locomotion mechanics. None of them are perfect, but each one has its merits. If nothing else, the variety of options illustrates the ingenuity of the VR developer community.

First-Person VR Locomotion Methods

Comfort Mode

Cloudhead Games designed one of the first VR locomotion systems that address the lateral motion issue. Early in the development of The Gallery: Call of the Starseed, Cloudhead Games found that linear motion with a joystick triggers sickness in some people, but short incremental adjustments don’t. The developer created a system called Comfort Mode that splits your rotation into short, instantaneous jumps instead of a continuous spin, which is surprisingly effective. For whatever reason, your brain accepts that your surroundings change in the blink of an eye, but it can’t reason with spinning scenery when you’re stationary.

Comfort Mode is one of the most successful options for seated locomotion. Many developers implemented the feature, or a variation of it, to their VR games.

Teleportation

Comfort Mode isn’t the only mechanic that Cloudhead Games pioneered. The developer also created the Blink system, which is widely used for standing and room-scale VR games. Blink allows you to teleport across the map so you don’t have to rely on artificial forward movement. It also lets you pinpoint an area within view that you’d like to move to and jump to it instantly. With Blink, you can also spin around to any angle.

When you activate Blink, you’ll see a round marker with an arrow on it. The arrow indicates the direction you’ll be facing when you move to that position. Sliding your thumb over the thumbpad allows you to change the direction you’d like to face, which helps when you're navigating cramped spaces.

Cloudhead Games developed the Blink system to address the limited play space of VR games, and many developers have taken advantage of the concept. Nearly all first-person VR games that require navigation through a map offer a Blink-like option.

Warp Speed

Blink isn’t the only teleport mechanic that you’ll find in VR games, though. CloudGate Studio, the developer behind the dinosaur hunting game Island 359, took the Blink concept and tweaked it to suit its game. CloudGate wanted to maintain the senses of dread and terror that fighting off dinosaurs face to face trigger, so it didn’t like the idea of instant teleportation. Instead of teleporting, CloudGate’s system is sort of like an adrenaline rush where you become hyper-vigilant and sprint to safety.

CloudGate also incorporated a stamina bar to its variation of Blink. The further you move in one burst, the more stamina you burn, and you must briefly rest to recover if you fully deplete your stamina bar.

Neat Corporation came up with a clever mechanic for its upcoming VR stealth game Budget Cuts. The developer incorporated a visual preview system for its teleportation mechanic that allows you to navigate through the environment without being detected. You can place a marker where you wish to move that gives you a live video feed of that space in a bubble in front of you. If the coast is clear, you can move forward.

Valve uses a bubble teleport system in The Lab to switch between games, but it doesn't give you a preview of where you're going. In the lobby, you’ll find bubbles at each station. To enter a mini-game, pick up the bubble and place it over your head. To exit a mini-game and return to the lobby, press a button on the controller to spawn a return bubble and stick it over your face.

How to use the bubble mechanic isn’t immediately apparent, but once you know what to do, the system is surprisingly intuitive.

From Host To Host

Damaged Core from High Voltage Software features a unique locomotion system—if you can call it that. Instead of figuring out how to move around comfortably, High Voltage Software decided to avoid movement altogether.

Damaged Core features a parasitic teleportation system. In the game, you play a parasitic energy that can take control of host robot bodies. You never move around as a host robot, but you jump across the map by switching from host to host. As one body wears out, you grab hold of a new one and continue the fight.

Not Everyone Likes Teleporting

Teleportation is undeniably one of the most comfortable VR locomotion solutions around, but it’s not for everyone, and it’s certainly not suitable for every type of game. Being able to move great distances in the blink of an eye feels like a cheat to some people. Admittedly, it’s not the best solution for competitive gameplay.

Trackpad-based artificial locomotion appears to be the solution of choice for first person shooter fans. Onward, a team-based competitive first-person military simulation game from Downpour Interactive, uses trackpad navigation, and it’s one of the most popular titles available for the Vive.

Trackpad-based artificial locomotion is like thumbstick-based artificial locomotion, but it’s not quite as jarring because it doesn’t take rotation control away from you. To move around in Onward, you press down on the touchpad. Where you press on the trackpad dictates the direction you walk. Movement is decoupled from the direction your head and hands are pointing, so you can look around and target enemies as you run across the map.

Still, trackpad-based artificial locomotion isn’t the most comfortable option, so we wouldn’t recommend it for a first-time experience. Even without rotation, forward movement when you’re not actually physically moving can trigger a vertigo-like sensation.

Swing Those Arms

The last locomotion option that we know of is called ArmSwinger. As the name suggests, to move around with ArmSwinger locomotion, you swing your arms back and forth. ArmSwinger is triggered by the grip buttons on each controller. Squeeze the grips and swing your arms at your sides as if you were walking at a brisk pace to move. The faster you swing the controllers, the faster you move in the virtual world.

ArmSwinger locomotion is available to developers, but we haven’t seen any games that use this system yet. Climbey uses a similar locomotion system for jumping, though. To jump in Climbey, you must swing both your arms at your side in unison to “push off.” The harder you swing, the higher you jump.

More To Come

Developers already have many choices for VR locomotion. Each option helps solve different problems and applies to various styles of games. However, none of the available options are suitable for the long run. Someone new must come up with an approach that satisfies a wider range of needs and consumer desires.

Or maybe it won’t be a newcomer. Denny Unger was recently a guest on The Voices of VR Podcast, where he revealed that Cloudhead Games is working on yet another VR locomotion solution for the second installment of The Gallery. Unger didn’t go into details, but he said his company would start talking about its new method before the launch of Episode 2: Heart of the Emberstone, which is due in the first quarter of 2017.

 Kevin Carbotte is a contributing writer for Tom's Hardware who primarily covers VR and AR hardware. He has been writing for us for more than four years. 

  • wisesocum
    heloooooo
    Reply
  • nutjob2
    "A vestibular mismatch can even trigger nausea or vomiting in extreme cases."

    This vastly misstates the seriousness of the problem, probably becuase the younger you are the less likely you are to be affected. But at least a quarter of people will suffer from crippling nausea for half an hour or more after 15 minutes of disconnected VR movement.

    "Vestibular mismatch problems became apparent in the early days of Oculus VR development."

    That's right, there was no VR before Oculus! They literally invented VR from scratch! Nothing about VR motion sickness was known before Luckey Palmer came down from the mountain and presented the result of his genius to the unwashed masses!
    Reply
  • kcarbotte
    18944857 said:
    "A vestibular mismatch can even trigger nausea or vomiting in extreme cases."

    This vastly misstates the seriousness of the problem, probably becuase the younger you are the less likely you are to be affected. But at least a quarter of people will suffer from crippling nausea for half an hour or more after 15 minutes of disconnected VR movement.

    You are vastly overstating the problem. And you are mistaken about younger people being less affected.
    25 to 40% of people are affected by "some degree of motion sickness." It's not nearly as common as you suggest for poeple to be crippled to that level from VR sickness. It happens. I've experienced it from a poorly designed game, and one of my closest friends suffers from terrible motion sickness, but to say a quarter of the population suffers that badly is to mislead the public.

    And the older you get, the less likely you are to experience motion sickness. Most people over 50 aren't vulnerable to the effects as much. Vestibular mismatch is much more likely to occur to younger people, particularly kids and teenagers, who's eyes and peception mechanisms are still developing.

    "Children over age 2 seem more prone to motion sickness than adults. Some experts think children's extra-sharp senses may make them aware of even a slight mismatch. Adults in their golden years seem to experience motion sickness less often—perhaps because of habituation."
    https://vestibular.org/news/06-18-2013/new-views-motion-sickness

    18944857 said:
    "Vestibular mismatch problems became apparent in the early days of Oculus VR development."

    That's right, there was no VR before Oculus! They literally invented VR from scratch! Nothing about VR motion sickness was known before Luckey Palmer came down from the mountain and presented the result of his genius to the unwashed masses!


    I never said it didn't start before Oculus. In fact, we've written about that fact many times.
    Doesn't change the fact that there were very few people working in that field until Oculus came around with its dev kits and exposed HUNDREDS OF THOUSANDS of developers to such realities. The research community discovered the problems relating to the vestibular system, but software developers didn't catch on until much later. It took hands-on experimentation to drive the point home.

    http://www.tomshardware.com/news/jason-jerald-vr-book-interview,31388.html

    http://www.tomshardware.com/picturestory/704-history-of-virtual-reality.html



    Reply
  • falchard
    I still like the frictionless running pad. It wil turn gamers into Olympic athletes.
    Reply
  • bsselp
    You're incorrect regarding the age issue. As you get older, you are more prone to motion sickness. That's the main reason older people have trouble with rollercoasters and get motion sick in their 40's when they never had an issue with them before. I am proof of one of those people. I could ride rollercoasters all day when I was younger but now I can't even go once without getting motion sick. I also get motion sick in VR often. Most younger people I talk to tell me they don't get sick at all. So unfortunately age is a factor.
    Reply
  • BrutalAttis
    46y here, I play allot of E:D, can play hours doing combat or even on surface in SRV. The latter I can feel a bit, but otherwise I am fine. I am only of those that HATE teleportation, and is the main reason I have not even bother with any game that supports that. What I like most to day it movement was in what was used for Luckys Tale. I hated Chronos for it movement of choice too. Would love to play a game like Dark Souls but with Lucky Tale follow camera movement.

    My experience with VR sickness had been that the more I played (not pushing yourself thought), the less it impacted me. The concept of VR legs for me was real. Quickly I moved up to be able to play for hours on end with minimal discomfort.

    Lucky I am more of an E:D player, and the only reason I got VR. Tactile Transducers in office chair + HOTAS in E:D VR is truly a great experience. My only grip is I would like to see double the resolution we have right now in VR. The bad resolution in VR is really off putting, making me enjoy E:D more at 34" 3440x1440p with a head tracker compared to VR.

    Come on, can we get the next gen VR units already.
    Reply
  • RomeoReject
    "I still like the frictionless running pad. It wil turn gamers into Olympic athletes."

    Agree so much. I know it's expensive, large and inconvenient. I know it doesn't work for certain people, such as those with disabilities. I know it provides a disproportionate advantage to those with a natural athleticism. I just don't care, it looks like the single most immersive system I've ever seen.
    Reply
  • poke50uk
    You forgot Unseen Diplomacy - which is entirely one-to-one around a massive environment.

    https://madewith.unity.com/stories/environmental-redirection-unseen-diplomacy-1
    Reply
  • cryoburner
    18946663 said:
    You forgot Unseen Diplomacy - which is entirely one-to-one around a massive environment.

    https://madewith.unity.com/stories/environmental-redirection-unseen-diplomacy-1

    That's an interesting method, though it seems far more limited in the kinds of games it can support. Essentially, you're moving one-to-one around a small area, but the rooms are changing just out of sight to give the impression of entering new areas. I imagine it wouldn't take long to feel like you are moving in circles though, especially if a game were to not have something like those zig-zagging ventilation ducts to get you crawling back and forth after every couple rooms. The navigable space within each room is always going to be small, and you'll never gain a good spatial awareness of your surroundings, since all rooms actually overlap one another. It might work fine for that game, or maybe something like a dungeon crawler, but ultimately its uses seem limited, where this article seems to be focused on locomotion methods for larger spaces not restricted by one's accessible space.

    It requires a fair amount of physical space too. Most room-scale VR games allow players to work with whatever space they have access to, while this seems like it simply wouldn't work on an area much smaller than the Vive's maximum.
    Reply