The Infinadeck Omnidirectional Treadmill - Smarter Every Day 192 (VR Series)

Hey, it's me, Destin. Welcome back to Smarter Every Day. A treadmill is a pretty simple device, right? You set the speed you want; you get on, you start moving. But you don't actually go anywhere. This technology people have realized for a really long time is perfect for virtual reality because you could walk somewhere and actually use your body but not leave the confines of your own home.

Okay here we are in California. We are at a company called Infinadeck. This is a small engineering outfit. These guys make a 360-degree treadmill, the one that's in the movie Ready Player One. So the interesting thing is they're a really small company, but they've got a really cool idea, so let's go check out how this thing works.

All right, so this is George, and he owns Infinadeck, right? Yeah. All right. And basically, Infinadeck is a 360-degree treadmill technique. That is, is it safe to say that we've got treadmills on top of treadmills here? It's a treadmill made of treadmills. Okay. Treadmill made of treadmills. So you can think of it as you've got one axis of rotation here, and each individual treadmill can move in this direction as well, right? Yeah.

So how do you? So it's a combination right? Obviously, if you want to go X. This is our X direction. This is our Y. X is nothing but a treadmill, you know, like any other treadmill. The Y is nothing but the smaller treadmills. Right now we're using the Vive tracker on you, right? So where is the, there they are right there. So your tracker's on your rear. We kind of artificially take you about seven or eight inches in front of that to get the middle of your CG. And this tries to keep that middle of the CG in the middle of the treadmill right there.

Oh, I got you. So the feedback – that was one of my main questions – is what is the feedback loop? It's a positional feedback loop. Yeah, it's fairly simple right now. We're making it better. That's the part we're gonna just keep improving forever, years and years and years, really?

So the goal, so you have an object and then, oh, I get it. It's this – this is called, they're very visual. This is a semi-autonomous command position sensor. That's the best specific way to say that, right? Now what we're also doing on this one is you put foot trackers on. When you combine the foot trackers, the headset, and your hand controllers, you now have six different points that are tracked on you, and that's enough for us to give you an avatar.

George Jr. told me if I screwed this little VR tracker into the bottom of the camera, we can insert that camera into the virtual world, which of course we had to do. So we're ready? Yeah. So I just – I just get in? Yeah, go ahead. So, all right, let me help you a little.

Okay? So first let’s do your feet. All right, this is the CG, you're gonna put that on. Make the tracker meet directly behind your back. Okay, so go on, put your headset. This feels like I'm actually getting in the Oasis here. Oh wow! I can see the camera in the virtual world. If you look towards me, you should see the two controllers? What the heck, man!

So we're gonna have you do now. Okay, okay. I'm trying to. This is just normal VR. So I can actually see the ring now. That's something I didn't expect, so I can – it’s there.

Yeah. Alright, so now that's – I see my body too. What's up with my body? So we're gonna sync that with you. So if I can have you stand with your legs straight down and your arms straight out to your sides, like a T-pose? Three, two, one. Did it work? Oh, I can see my body! Wow!

Alright. Okay, that's rad. That's really rad. Okay, gotcha. So right now you're tracking the position of my hands and my feet? Dude, that is messed up! This – I’d like him – alright. So I can see the camera, the tic-tac there, but what's more important is I can also see this ring.

And Griffin, why did you say you have this ring in here? So this is there to kind of lock you down in the real world without being too much of a burden to say. So this is like, you know when you do an integral you get the plus C at the end. So this is a boundary condition for me to kind of lock my brain into both worlds. So this is like, this tells me where I'm at virtually and like actual my body, right? Absolutely.

Okay, so are you ready to start walking? I'm ready to start walking. We're gonna recommend you have your hands on the range when you first try this just so you get used to it. That's okay, so when you start. Yeah. I thought it would make sense for you for it to put me in the center, okay?

So now, right? What is trying to do is this trying to keep the CG of my back in the center of the ring, right? So I'm gonna touch this and as I walk. Okay, it takes just – okay, I'm there. Okay. I don't want to hit that tree, so I'm gonna turn this way.

Okay, so I can't really tell if I'm walking 90 degrees or not. Okay, so there's inertia in the rollers, okay? I thought there might be. So if I move backwards, it's gonna keep me there. If I move forwards, so it takes just a second. Just a couple of seconds on the Infinadeck, and I instantly understood the problems that these guys have to overcome.

It's pretty interesting. It seems pretty simple: whatever direction a person walks, the Infinadeck moves in the opposite direction, whether it be X or Y, at the exact same velocity and acceleration. Think about a normal treadmill: your brain is doing all the processing. Your brain is constantly solving the equation – a treadmill velocity plus body velocity equals zero. If at any point you don't solve that equation correctly, you start moving relative to the treadmill.

This is a very similar problem, but it's much harder. It's harder because there's two dimensions; that's the obvious one. But it's also harder because the processing isn't happening in your brain. That processing is offloaded to the Infinadeck, which, oh by the way, can't read your mind. There's a delay time for the Infinadeck to figure out where your position is and try to change that... Yeah. Yes.

...and if it tries to do it too quickly, you know, you can have an overdamped and underdamped system, is that correct? Yeah. Is that the right terminology? So, yeah. So at the moment, what we're currently doing, we're trying to make it so that the acceleration on the user in any way that they're not really trying to experience is never more than 0.1 Gs. Got it. Oh, that seems to be about a good amount to not really be, you know, disturbing for the user.

Okay. We're trying to figure out where exactly that is and how to do that. If I walk forward, I'm gonna feel an acceleration in one direction on my body because I'm pushing against the floor, right? But then the floor is gonna move, and it's gonna move my body in the opposite direction, so I'm going to feel an acceleration that's negative, which is strange for, you know, a normal walking around human.

Then, once I hit a steady state velocity, I'm gonna level out that acceleration in my mouth. My body's gonna be cool with it, right? But the moment I stop, that's a change in velocity, and the Infinadeck has to accommodate for that. It has to move you back to the center gracefully, and one thing that happens is if it tries to move you back too fast, it'll overshoot, and then it has to correct.

So this is a really interesting engineering problem because it doesn't have perfect knowledge of intent. Like, that's the difference with your brain; you have intent. And so when you're walking in a normal treadmill, you get to choose everything, right? But you have to understand over the last few years we had to build and modify the Infinadeck too along with the control system, and there's only a few of us, so... Well. It's been challenging all around.

This is why the problem is interesting because when you're walking in the world right now, my acceleration is zero. And then when I stop, I'm used to imparting acceleration to my body, but that doesn't happen till later. Yes, it's a work in progress how far you go back. That's clever. That’s a challenge. That's a hard math problem.

One thing I thought was really cool is you can use this to be a different size in the virtual world just by changing a constant, right? You can scale how many steps it takes to get around in the earth just by a scale factor, but literally a scaler, that’s often. Oh, there's the same boat; look at that.

It's a dude. It's like I want to jump! I'm just too small to get it. Too small to go to my boat and laughs That's fun. That's really fun that the model... There's my bench. Look behind you, there's my bench!

Before, in engineering, we have these assignments called technology readiness levels. There's nine of them, and I would say this is somewhere between a six and a seven, which means there's a working prototype that works, and they're just refining the subsystems; they're about to go to production.

So it's really cool to be able to walk on this Infinadeck before it goes out into mainstream production and see the behind the scenes engineering things they're having to solve. It's really interesting. So, it's clear George knows all this. I mean, he instantly understands all the variables I asked him about. That how tall the person was, like if you think about it, your center of mass is at a different length, and so that moment arm is different; you have to deal with inertia differently, like from the bottom of it.

It's really interesting. Anyway, this is me talking to George, and you can tell he totally gets it. I can imagine that the inertia, overcoming that inertia is different for each person because if I'm 175 pounds and I move here, it takes a certain amount of torque. I'll cut the deck off now. It takes a certain amount of torque for these motors to move me, and that's going to change based on the size of the person, is that correct?

That's correct. It's more about your acceleration than the inertia. The deck is capable of moving a lot faster than you can move. So we could pull your feet out from under you if we ever, you know, had it set to do so. So all the algorithms and stuff will have more to do with other variables, like your CG, CG imbalance. And there's a moment arm between the distance from my feet to where my CG is, right?

So, so the acceleration that you put there, there's gonna be this lag time in my brain where I try to counteract that, is that correct? Very much. Alright, this is the part of the video where I tell you about the sponsor, and, you know, a lot of people fast-forward through this part, but you know this is the important part because we wouldn't be doing this if I hadn't have listened to Ready Player One on Audible.

I'm not gonna tell you about Ready Player One; you know that's old news at this point. I’m gonna tell you about the new book that I'm listening to. The sponsor is Audible. You can get a free book by going to audible.com/smarter or texting the word "smarter" to 500-500.

The new book that I'm listening to is called "Twelve Rules for Life" by Jordan Peterson, "an Antidote for Chaos." Now, I'm listening to this book because I heard some podcast with the author. There's a lot of people talking about this book, and I wanted to check it out because he doesn't believe things that I believe. In fact, he takes a third party-like perspective look at some of the things I believe, and so that helps me get outside myself and grow a little bit.

So I really enjoy it. If you're not listening to audiobooks, you really should be. You're smart people; you know this part is a big deal for me, and I know this part can be a big deal for you because audiobooks literally have changed my life. So, Audible.com/smarter, that's how you can support Smarter Every Day or text the word "smarter" to 500-500. Thank you for considering that.

Last thing. I want to say thanks to the guys at Infinadeck. A treadmill made of treadmills, that is insane. You're there, man, this is just a control systems problem at this point, isn't it? We just need some control engineers. We ought to hire a couple.

That's what this is at this point. At this point, it's just computer stuff and math, so this is doable. I hope you enjoyed this video enough to subscribe. If you do, there’s a little bell beside the subscription button. If you haven't enjoyed it enough to hit the bell to get a notification on your phone every time I upload, then don't. That's completely okay.

Anyway, I'm Destin. You're getting Smarter Every Day. Have a good one. Thanks for learning with me. You're gonna fall. You fell. You jumped. Whatever. What are you doing? Why you making noise?