Solving VR’s infinite walking problem with moon boots
“It’s about continuity of experience,” said Brad Factor. “It’s about maintaining that immersion. It’s about ease of use and the learning curve: you don’t need to teach someone how to use VR, just be able to put on your headset and experience the virtual world naturally. That’s a lot we’re focusing on.”
Factor, the founder and CEO of a company called Ekto VR, has invented what is, in essence, a pair of chunky, cyberpunk-looking moonwalking boots for use in virtual reality environments. If Dorothy wore ruby slippers to travel safely through the magical, technicolor land of Oz in The Wizard of Oz, then Factor’s invention is designed to enable equally safe travel through virtual reality.
Have you ever wondered how it is possible to create a convincing virtual reality scenario that allows you to, say, walk through the Sahara desert without the painful experience of colliding with a wall in your apartment? Ekto VR thinks it has the answer: Throw on a pair of the company’s simulator boots over your regular shoes, put on a VR headset, and you can experience walking through virtual environments that are much, much larger than physical space. it is contained within.
The Ekto VR boots work by using a series of motorized wheels on the bottom, which rotate in the opposite direction to the speed at which the wearer is walking. To prevent motion sickness, the boots allow the wearer to initially take several steps forward. This is done to provide the necessary vestibular signals from the inner ear to tell their bodies that they are accelerating forward. However, after a few steps, the boots automatically slide the wearer back to the center of the room so they appear to be walking in place, as if on a treadmill. In the meantime, the user believes they are continuing to make progress, and based on the VR scene they are experiencing, they are.
“As far as the feedback we get the most at the demos, people are almost completely convinced (and, in some cases, completely convinced) that they will walk out of the room,” Factor told Clear Tips. “People ask us, ‘Are you [the boots] about? They are working? Am I getting close to the edge? [of the room]?’ It’s really like they don’t have any sense of where they are. They’re immersed in the environment to the point where they’re not sure they’re still inside the room they started in.”
(Note: Clear Tips hasn’t been able to put these shoes to the test ourselves.)
Before he started creating virtual reality boots, Factor was employed by Honeywell Aerospace, where he spent eight years building flight control systems for planes like the Boeing 787 Dreamliner. In that case, he was responsible for some of the core technologies that allow 200-300 people to sit at once, seemingly stationary, inside a large metal tube, before emerging thousands of miles away at their destination.
Now he’s working on the inverse of that problem: keeping people in a fixed location while tricking their brains into thinking they’re traveling great distances. If he can crack it commercially, he’ll be the first, but he’s not the only one to try.
The problem of endless walking
Ekto VR is not the first company to try to solve the problem of endless walking in virtual reality, sometimes referred to as the LI (locomotion interface) challenge. Efforts to do so date back to at least the 1980s. In Howard Rheingold’s 1991 book Virtual Reality: The revolutionary technology of computer-generated artificial worlds and how it promises to transform society, tells the author using a VR treadmill at the University of North Carolina.
Paired with a VR headset, the treadmill allowed users to walk through a virtual version of Sitterson Hall, now home to UNC’s computer science department. In doing so, the virtual reality demo made it possible to experience what it would be like to walk through a full-size, three-dimensional version of a building that was still in the construction phase.
“I was able to walk down the halls of an entire building without physically leaving a small room because I was walking the length of a treadmill, holding on to a pair of handlebars,” Rheinghold wrote. “When I wanted to turn right and discovered what was at the end of the corridor that I could see stretching out in that direction, I turned the handlebars and kept walking straight. It took me a minute to get used to it.”
Aside from UNC, other attempts to solve the endless walking problem took place at the University of Utah, which developed a machine called the TreadPort. It featured a large treadmill with a tilting mechanism, combining locomotion interfaces with the visual, auditory, and olfactory senses, and even radiating heat and wind elements.
Much work has also been done in Japan, particularly at the University of Tsukuba. “I would say you could point to all the solutions out there today, particularly the hardware ones, and say [that researchers at the University of Tsukuba] I already tried it,” Factor said. “They made an omnidirectional treadmill. They did something very similar to the starting point we had, called motorized shoes. They made a rope walker. They tried, like, eight different approaches, maybe even more. I don’t think they tried to push any of them forward. [to the point of commercialization].”
More recently, researchers at Unity Technologies Japan developed an innovative solution to the endless walking problem, which creates the illusion of an infinite virtual corridor within a “play space” that measures 16 x 22 feet. Called “redirected walking,” the approach aims to trick the brain into thinking the subject is walking in a straight line when, in fact, they are walking in a giant circle.
Yet another approach, developed by researchers at Stony Brook University, Nvidia, and Adobe, does something conceptually similar by using an eye-tracking HMD (head-mounted display) to detect users’ saccades, the rapid movements of the eyes that occur when people are looking. at different points in our field of vision, for example, scanning a room. By effectively “hacking” these saccades, it is possible to redirect users’ gait direction without causing dizziness or discomfort.
“We are the most complicated biological system, certainly more than any treadmill, for example, right?” Qi Sun, lead author of the study, told Clear Tips. “So why don’t we use the most common but complicated machine, ourselves, to enable that kind of experience that we want to solve? That was the original, highest-level motivation for this investigation.”
What’s interesting about the myriad of approaches to solving the endless walking challenge is that, even several decades later, there is still no agreed-upon solution that has caused researchers to dismiss all others. No one has yet created the perfect commercialized solution that clearly lights the way into the future. That means there is not only a lot to play for in terms of who owns this market, but also the details of the approach taken.
The next big thing in virtual reality?
Will locomotion interface technology be the next big thing in virtual reality? Much depends on whether virtual reality is ultimately about creating virtual worlds or simply providing a new kind of interface. If it’s an interface, predominantly used for practical applications like the VR equivalent of Zoom meetings, this kind of realism may not matter as much. In that case, being able to walk long distances in VR might not only be unnecessary, but also a detriment to the user experience. For example, a VR version of shopping doesn’t necessarily need to replicate the experience of walking down the aisles and carrying an increasingly heavy basket. That would be a huge discount next to the seamless ease of Amazon‘s one-click shopping.
On the other hand, if the most compelling use cases for VR come from creating compelling virtual worlds, solving the locomotion problem is absolutely necessary. Study after study has shown that subjects find VR environments more immersive, with a greater subjective sense of presence, when moving through virtual walks rather than, say, teleporting between locations using a handheld controller. As a 2004 study from researchers in Japan put it, the sensation of walking affects people’s “cognitive maps,” the way our brains process distance and movement. In short, walking adds verisimilitude to virtual reality that can trick our brain into perceiving what we’re seeing as real.
Gaming is a great example of a use case that will only get more compelling the closer the experience gets to reality, but not just for gaming. For example, if you’re an architect who wants to show a commercial real estate client what the layout of a new shopping center will look like when it’s built, you’ll be able to walk through a virtual version of the building (as Rheingold said over 30 years ago). years) would be very beneficial.
Industrial applications and beyond
As for Ekto VR, Factor said his company is initially targeting the latter type of industrial applications.
“When you get into the type of major [VR] training applications, talking about refineries, pipelines, offshore platforms, manufacturing facilities, or aircraft inspections, people will say, ‘Well, [we could just use an interface that teleports users around it,]he said. “That’s great from a performance perspective if what you’re optimizing is you need to see areas that are completely independent of each other quickly. But we’re getting further and further into these more comprehensive scenarios where you need to do a full inspection of the skin of the plane or see how something in the tail wheel [of a plane] connects to the nose wheel, or a valve in one plant affects a condenser elsewhere [of the building]. These really require you to understand your surroundings much better. [and how they spatially relate to each other.]”
With those kinds of industrial applications in mind, Ekto plans to launch its partner beta program in the first half of 2022. As for pricing, Factor said the company is still weighing its options, from offering kits for sale or lease . Exact pricing has yet to be announced, but an initial buyout would likely be in the $15,000-$20,000 range.
“Now obviously those kinds of pricing that we’re talking about, they’re not for the consumer, and to some extent they’re not even really suitable for most enterprise use cases,” Factor said. “A lot of it is low volume at this point. As we increase volume, we expect to dramatically reduce costs and prices.”
Eventually, he said, the company will try to sell on the market at prices below $1,000, making it a more attractive proposition for everyday applications. That includes the prospect of more consumer-facing use cases.
Endless walking isn’t the only missing part of the VR puzzle. Simulating touch, smell, taste, and more are other yet-to-be-resolved areas that are just beginning to attract the attention of forward-thinking researchers. Expect to see a lot more of this in the coming months and years. After all, the hype surrounding virtual reality, one part of the larger concept of a Metaverse, hasn’t been hotter in years.
Whatever you call it, we’re going to be spending a lot of time in virtual worlds, so getting it right is crucial.
