[MGW 2018] The new locomotion methods of the future for Virtual Reality

    Since I’ve got hooked on Virtual Reality, it’s clear that if there’s one aspect that the developers haven’t agreed on yet, it’s locomotion systems. What’s better for the experience? Which one can make less experienced users dizzy? Above all, which method allows the player to be part of the virtual world they are visiting? Then this year, thanks to the movie «Ready Player One», we have seen the dream that many of us imagine: to walk ourselves, and that the character walks in the same way.

    For all these reasons, the studios keep looking for innovations in this field, and during the Madrid Games Week three very different proposals were tested at the Jugón Virtual booth. These are two omnidirectional platforms (Virtuix Omni and KAT WALK Mini), and a software system (Natural Locomotion update from Myou Software) that works with sensors on the legs. After testing all three methods, which one works best and which one could have the best future for a massive implementation among users?

    Virtuix Omni

    The company that brought the Virtuix Omni platform was Prisma VR Studio, which is responsible for developing different types of VR experiences for companies, and are looking to market their titles both in Arcades VR around the world, as in Steam and consoles. Among the experiences they have developed, we have a basketball experience that works with realistic physics, another football experience where we can be the shooter (thanks to sensors in the legs) or the goalkeeper, one in which we can run in the San Fermines without the real life danger or animal suffering, and the one they showed in the Madrid Games Week in Virtuix Omni: a zombie survival experience called Be a Survivor set in Spain, with the recreation of the Plaza Mayor in Medina del Campo.

    But let’s go to the focus of this article: the omnidirectional platform. This platform is probably the best known, having been in development for many years after a successful Kickstarter, and show on YouTube quite a few games running with it. This promotion was one of the reasons why I was so eager to try it, and the sensations were more or less positive. The platform works like a directional pad, having to carry some platforms on the shoes so that we slide through it. Thanks to this slide, the game is able to interpret in which direction we move. In addition, we are hooked with some harnesses to avoid flying away, something that would happen very easily without them.

    Displacement is more or less natural, having to really lift your legs to walk, as we would in real life, and the sliding on the platform is smooth enough so that we can continue walking without feeling like we’re falling, something that can happen on some other displacement platform that is in development. Even so, it’s not something tremendously intuitive, since at first it’s hard to get used to how everything works. It is not necessary to leave the circle, but simply take small steps, or that was the impression I got. In the 3 minutes or so that the experience lasted, I didn’t have time to get used to it, although at least, it was fun to go shooting zombies with a rifle in which the HTC Vive controller was attached.

    Apparently, Virtuix Omni works with two types of sensors. On the one hand, the supports we carry have small trackers that measure the displacement we do, so the surface as such only serves to slide, but not to measure the steps or direction. On the other hand, in the waist harnesses there are many other sensors, which serve to measure the direction in which we move. Thanks to this combination of sensors the platform allows us to run, walk, move sideways, etc.. At the same time, the harness keeps us restrained (maybe even too much to feel natural), so that we are not in any danger.

    Natural Locomotion by Myou Software

    From a big contraption we went to a software solution developed here in Spain, and that like the other two platforms, could be used in all games that employ some kind of free locomotion. The advantage of Myou Software‘s Natural Locomotion in its next update (right now the system works with the movement of the arms) is that it only requires the API that the studio itself has developed to translate our movements into the language interpreted by the game, and two sensors near the feet. These sensors can be the official trackers of HTC Vive, two Switch Joy-Con or even PS Move controllers. In these last cases, it is necessary to use an adequate support so that they don’t fly away, and the studio itself will give the model to print it in 3D (it’s what they use themselves), or they will sell them on eBay.

    And how does Natural Locomotion work? Basically, before playing we have to take about four steps on site to calibrate the sensor, and then we play. The idea is to make the gesture of taking steps, but staying in place, in a way similar to what Kinect used in quite a few of his games. Maybe that’s why it was so natural to me, because it seemed like a completely natural motion scheme. The game they had to try out was Gorn, the popular all-violent, arcade gladiator wrestling title, and it worked great. What if I wanted to go after an enemy? I started to lift my legs and without problems. The technology is also able to recognize the rhythm that we have, because if we make the gesture faster, we will start to run inside the game. All this made me have a great time while testing the technology and the game, being a delight to take a couple of weapons, walk to a gladiator, and bust his head as if we had two hammers in our hands. By using HTC Vive, you could rotate without problems and keep walking, all in a very, very natural way.

    Some of the other games that Natural Locomotion is already compatible with are heavyweights like Skyrim VR, Apex Construct, In Death and many more titles. If a release was not compatible as built-in, the API to implement it is quite simple, and they would make it available to interested developers at no additional cost.

    Although my experience was very positive, it is true that «walking in place» may sound strange to more than one, and certainly, it was normal to see at the fair quite a few users who began to physically walk themselves, until almost leaving the booth. The cable can be an additional nuisance, but with the new wireless solutions that are coming to market, this would be solved relatively easily.

    KAT WALK Mini

    This onmidirectional platform was brought by VRX Sim, and it was the one I knew the least until recently that I got more into the world of VR. In essence, this platform comes in two formats: a larger one, and the Mini version, which was the first time it could be tested in Spain. Despite the «Mini», KAT WALK Mini is still a platform of considerable size, which again, can be applied to any game with free locomotion.

    The demo I was able to test was a firing range that had to be moved on foot using two HTC Vive controllers that were inside gun-shaped supports. The goal was to finish the circuit with the highest possible score, so there were no enemies or anything like that. Other days at the fair I saw that they put more active games where there were zombies or things like that, but what I want to focus on is how we can move.

    Instead of using special platforms or shoes, it was necessary to be barefoot, to make friction in the platform thanks to the socks. In KAT WALK Mini I think movement is measured by sliding, because if you walk normally, lifting your leg a little and then moving (in this case, sliding your foot back to its original position), the game barely recognized movement. Instead, we also had to slide forward, as if we were doing the «Moonwalk». Yes, it’s quite weird, that at first you move as you can, making much more effort than we would normally do to take a normal step. This is the main problem I see with this platform, because although we can adapt later, it still doesn’t feel completely natural. Maybe it depends a bit on what game we use and how it’s implemented, but I do find it strange. Apparently, this platform has other interesting advantages, like being able to jump, something you can’t do with Virtuix Omni, for example. However, in just 5 minutes you don’t have time to fully adapt or try these more advanced moves.

    Conclusions - Better system and overall advantages

    Despite the different proposals, one advantage provided by these locomotion systems is the same: the reduction of dizziness or motion sickness. This dizziness is due to the perception of our brain, since we perceive movement without executing it, reason why the mind becomes «crazy» and causes the sensation of dizziness. In this way, when we move we do perceive movement, so in theory, should help overcome this important problem. Then there will be the games of ships where the dizziness can come from other sources, but that is already another matter.

    However, the differences are very clear between these systems, and if I had to choose one option, I would definitely choose Myou Software‘s Natural Locomotion. That something so simple works so well seems incredible to me, since we make natural movements (especially if you’ve already spent hours on many Kinect games in which you «walked») and it’s very precise, at least with Gorn. The fact that it doesn’t require a lot of space, is the cheapest option and we can even use Switch or PS4 controllers, helps to make it a totally accessible system. It seems to me even more natural than what Cybershoes offers, another more economical locomotion option that requires less space than omnidirectional platforms.

    Regarding the two platforms, Virtuix Omni convinced me a bit more, since I noticed more than I was taking steps, while with KAT WALK Mini the «Moonwalks» would come in luxury if we are Michael Jackson, but it seemed too much effort to walk. This is something that can be applied to both platforms really, but I appreciate their existence. As with the VR, we are in the first steps, with which everything has to evolve, and as a first step, I find something very interesting to finally be in front of what we can see in «Ready Player One», and what I imagine, we all want to enjoy VR at the locomotion level.