In this episode we speak to Elena Kokkinara, CTO at Inflight VR, a VR platform developer for in-flight entertainment. We discuss how VR has developed over the last decade, how the body ownership illusion can make you feel like you have an entirely different physical body, whether developers can code in VR environments, and whether AR is in competition with VR.
About Elena Kokkinara
Elena Kokkinara is CTO at Inflight VR, the first company that provides a VR entertainment solution for airplane passengers. Having completed a PhD in VR and published numerous papers on VR and computer vision, she is passionate about creating new experiences for Virtual Reality users and gamers. Her scientific interest is to explore the necessary parameters to design a flight-specific VR ecosystem.
David Mytton (00:05): Welcome to the Console podcast. I'm David Mytton, co-founder of console.dev, a free weekly newsletter highlighting the best and most interesting tools for developers. In this episode, I speak with Elena Kokkinara, CTO at Inflight VR, a virtual reality platform developer for inflight entertainment systems. We discuss how VR has developed over the last decade. How the body ownership illusion can make you feel like you have an entirely different physical body, whether developers can code in VR environments and whether AR is in competition with VR. We're keeping this to 30 minutes. So let's get started. I'm here with Elena Kokkinara. Elena, thanks for joining the Console podcast.
Elena Kokkinara (00:50): Thank you for inviting me.
David Mytton (00:52): Let's start with a brief background. Tell us a little bit about what you're currently doing and how you got here.
Elena Kokkinara (00:58): Right. So I'm currently the CTO of Inflight VR. It's a company where it makes entertainment solutions for inflight, for airplanes, basically, using VR technology. My background is on virtual reality. Basically I did a PhD on virtual reality and I come from computer science. I studied computer science and computer graphics in a master's degree.
David Mytton (01:23): Let's start with the use cases for VR then. Is it primarily gaming? Is that what everyone always thinks of?
Elena Kokkinara (01:30): Not at all. VR, it's been around for 20 years and I think it's only the last five years or so that it has become popular with the gaming community. Health and education have been benefiting from it and they have a lot to gain from there and other sections too, other sorts of entertainment, a lot of use cases really and less.
David Mytton (01:53): So how have things changed over the last decade?
Elena Kokkinara (01:57): It's a funny question. I've been there for a little bit more than a decade and I've seen a huge growth. At the beginning, it was mainly used for research, very expensive and bulky equipment, and really very limited people had access to it, right. You had to have a lot of funding to get it and use it and there were really few real world applications. I think at the beginning, it was mostly health related or in the U.S. military related fundings that you could find to power this type of research. But then one day the consumerware headsets appeared with the Oculus DK1 and everything changed, right. Actually, I have an anecdote to share with you that in my academic career, I was working on a project that was, how could you bring VR in an airplane in the future aiming for 2050.
In the middle of the project, of the three year project, the DK1 appeared, and we could try already, actually within the same project, we could try VR in an airplane. So it was all very fast. Now everything became smaller with very, let's say, low visual quality at the beginning compared to these very expensive equipment, but it was very affordable, right. So it became a trend. Slowly, the quality became much better. We have lighter headsets also now, more comfortable, less equipment. Now we have the inside out cameras. So you don't have to have all these external cameras to track the system and everything. So it's still very expensive, I would say for the consumers. Then we have also the standalone ones that make everything super much easier and portable and everything. Yeah, everybody wanted to develop in VR. So unity and unreal, the game engines, they were creating a lot of support along the years, right. So it was easy also for the people to develop, but it's been there for more than 20 years and it has been developed only the last five to seven years quite a lot.
David Mytton (04:14): Right, and that was triggered by the release of the Oculus.
Elena Kokkinara (04:20): Yeah. Definitely. I would say. Yeah.
David Mytton (04:23): What was it about Oculus that was so revolutionary?
Elena Kokkinara (04:25): I guess the chip equipment, chip materials, the tracking was good. It's the main challenge for VR and everybody could use it for one very small percentage of the price of what there was there before.
David Mytton (04:40): Yeah. Okay. So the headset and the Oculus, that's what everyone thinks of when they think of VR. Is that still the primary user interface?
Elena Kokkinara (04:51): I would say yes. I mean, at the beginning there were other type of VR, like The Cave, I don't know if you've heard about, it was a room that you had the projectors in all the sides of the room and you could wear glasses and then you could see in 3D and you felt you were inside the 3D space, but I think nobody's using this anymore. It's very expensive still. But yeah, it is this type of headsets, really. They're getting smaller with less cables, as I said, more comfortable. They now start becoming, having these more sunglasses like style, the smaller we manage to make the processing power hardware. We need the smaller devices we get and I think this trend will keep going. I don't know. Maybe one day we will arrive at these contact lenses, black mirror vision that many people have.
David Mytton (05:43): Yeah. Okay. So when you go into a VR environment, how does our perception change?
Elena Kokkinara (05:51): Well, basically the essence of VR is this sense that you are immersed, right, and you forget the real world and you feel like you are somewhere else. You feel like you are really there. That's also the sense of presence as we call it. The way this works, it's very similar to the real world, right. So we feel and we understand the virtual word in the same way as in the real world with our senses. Vision, hearing, touch, even movements of our own body, right, and the trick is that these senses, they are contingent between one with the other. If we see something and we see something touching us, this has to be consistent in order to believe that it's real. Okay, that's what makes us believe it's real. Or if we move our body and then we have a virtual body, the body needs to move in a similar way in order to feel believable.
We call this a sensory motor contingencies, and this is essential to make this perception feel realistic. Now there is another parameter there, which is the adaptivity and the plasticity, let's say of our brain, and we can play around with this because our brain learns to adapt to small inconsistencies, right. So we can bend reality. Think of the mouse movements, for example, right. You do very small movements, but you see in your screen much bigger movements and you still understand that it is you that is doing this. It's similar in the virtual world, you can play around with small inconsistencies and you can still believe it's real, but you change the perception, right. So you can think things are further away or your environment is bigger or your body is different or you can make people believe they're flying. So we play with the plasticity of the brain in order to change perception and this is what makes VR special, because if you just want to replicate reality, what's the value of it?
David Mytton (07:54): There are a few challenges that people probably have experienced with this around motion sickness and using devices for long periods of time. How's that changed and what do you see as the solutions to that?
Elena Kokkinara (08:11): This is always going to be a challenge, right. So motion sickness, it's mainly the content creator's responsibility to avoid. I think that the hardware it's good enough to provide everything we need. We have good processing power. The field of view is getting bigger and bigger, resolution is almost now we can even have 8K resolution. So all these hardware components are more or less there, but then if the content creators make it wrong, you are going to feel sick, right. So if there is movement, fast movement, sideways movement, up and down because your brain basically is not able to adapt to these big changes, right. Your balance system knows you're not moving, but then your eyes tell you you're moving then you get sick. So there are good practices to follow. If we follow them, we are good. Then there are also the graphical components. So we cannot make too heavy graphics because this will cause latency on the rendering.
So we need to be careful there too. Well, that was always the case also with video games. You couldn't make something super expensive procedurally, because it will have latency. So there, we have more limitations with VR because there are two cameras that trend there at the same time, in the same environment. So double the processing power we need. In terms of eye strain, which is this tiredness you feel in the eyes after using it for a long period of time, it's going to be there. This is not going to change. It's like your computer screen. You need to take breaks after 20-30 minutes and look far away because your eyes basically converge in something that 's a few centimeters away from your eyes, right. So the muscles don't don't work and you get tired. I don't think this is going to change unless we go into this lens' vision again and then it allows you to look in and out whenever you want.
David Mytton (10:24): Yeah. Okay. You mentioned the resolution as being an important factor and you can get to 8K. Now, is that sufficient, is that realistic enough, or do you think it'll go further?
Elena Kokkinara (10:35): I think that's good enough, as long as you don't see the pixels, is good enough. But yeah, I mean, if we talk about realism in general for graphics and so on, if the resolution is good enough, then you've solved most of the issues. But in terms of graphical realism, I mean, there is research that suggests that it's not that important. I bring video games as an example all the time, because things are very similar. It was never important realism. Unless you look for it, unless you want these impressive environments, but it's the engagement that makes things feel wow, and it's the sensory input that makes it believable as I explained before, the way you combine your senses. So yeah, realism is important if you are looking for it.
David Mytton (11:24): Yeah. So I suppose it depends on the use case, games like Minecraft, they're not realistic, but that's all part of the aesthetic of the game, isn't it?
Elena Kokkinara (11:32): Exactly. Yes exactly.
David Mytton (11:34): Yeah. What about peripheral vision? How important is that?
Elena Kokkinara (11:39): This is important. If there is not a big field of view, you can also feel uncomfortable after a certain period of time. So right now we can simulate good enough with the most popular headsets, whatever the human eye can cut. It's not there yet, 100% of course, but it's good enough. I think with 110-115 degrees of horizontal field of view, it's good enough. When you get less than 100, then you have this window effect. You feel like you're looking at the word through a window, which makes everything less realistic also.
David Mytton (12:21): Yeah. Is that a computational challenge? Is it like additional screens essentially on the side, or do they use curve projections? How does it actually work?
Elena Kokkinara (12:32): It's mainly a hardware issue, I would say. It's not that much of a rendering problem. Nowadays, we have these pancake lenses that they try to wrap. Let's say what you see a little bit. So even though the screen is smaller, it somehow amplifies what you see. Okay. It's like a lens in front of the screen that somehow amplifies the view and then you can do some tricks on the rendering to make it look stereoscopic and correct. We have achieved a few things with that, but then there are other challenges, like how do you make it look okay for every type of facial features, right? So you have to correct for interpupillary distance. There are challenges and until we get into this rounded, let's say, screens where basically you can allow for covering more of your vision, I don't know if we are that close technically, but I hope we get there at some point.
David Mytton (13:38): Okay. Makes sense. You've written in the past about this concept of body ownership, illusion. What can you tell me about that?
Elena Kokkinara (13:48): This is, again, related to what I talked earlier, the sensorimotor contingencies, right. It's like how you trick the brain to make them believe that what you see it's realistic. The idea basically comes from 1998, I think, from some cognitive scientists, Botvinick and Cohen, that they came up with this rubber hand delusion, right, that was not related with VR. It was basically that you would put a person's hand in front of them and then you had a rubber hand and you would hide the real hand from the participant, like with the experiment, but the person would only see the rubber hand. The experimenter would touch, synchronously, your real hand in the rubber hand. So after a few seconds of touching in random places the hand, you would feel that this hand is your hand, the rubber hand, you felt it was your hand.
It's a very, very strong illusion and it works most of the time. What they would do at the end is that they would go to stab with a knife, the rubber hand, and you would move away your real hand because you thought it was yours. That's the way they measured that you felt it was yours. So a few years later we took this concept and we tried it in VR with synchronous touch of what you would see, like something would touch you in the VR, like a digital ball and then in the real world, a tennis ball would touch you. The ball was tracked and you could see it. It was synchronous. The illusion of this hand, this virtual hand, it's yours, really and if something hurts, it can affect you. It was very strong. So then this virtual hand illusion was transferred into the whole body illusion.
You could play around not only with stats, but also with movement. So if you see the movement of the virtual body being synchronous with yours, you feel it's yours. Whereas if the movements are not synchronous or if the stats are not synchronous with the ball, you don't feel this, right. So extremely strong. Then you can do all sorts of things like change the perception of your body, like showing that you have a bigger body with a very, let's say long hand or a very big belly. Then if you have synchronous stats or movements with this virtual body, you would feel that, oh, I suddenly have a very long hand or a very big body, or I'm a child or whatever. There are so many things you can do with this idea and it's very, very powerful.
David Mytton (16:29): That does actually work then, so you've tried that in real applications?
Elena Kokkinara (16:33): I've tried it with thousands of participants in my experiments and it always works, always. Almost always, let's say 95% of the time it works.
David Mytton (16:44): Excellent. So you can become different characters and completely change your appearance in the virtual world.
Elena Kokkinara (16:50): Yeah. Not only you can change the perception of your appearance, but with [inaudible 00:16:56] so that you can change behaviors. So for example, you would put yourself in a body of a different color and your racial bias would change.
Or I don't know, nowadays there are other experiments, like they put you in the body of Freud and then you can give advice on yourself, better advice on yourself and play with these types of concepts. Crazy.
David Mytton (17:23): So all of these interesting concepts, how would someone actually go about putting them into use in an application? If you are a developer, where do you start with building VR applications?
Elena Kokkinara (17:36): I think that most of the people come from a gaming background, right. Gaming development, because it's all very, very similar unless you don't play so much with graphics and you go directly with, I don't know, 360 videos, which is another category altogether. But yeah, mainly it's similar to developing games, you need design, you need art, then development testing. The user experience, it's a little bit different, the user experience design, because there's the whole concept of immersion and presence that you need to consider and these are different from, let's say, gaming design or website design, right.
It's a completely different thing, different dimension also. So yeah, user experience designers need to kind of educate themselves around virtual reality specifically. Then in terms of art and development, if we want to again with video games, the only thing is that you need to learn how to optimize for VR, both VR and the development, right. Everything needs to be lighter. The graphics, the geometry, the textures need to be good for VR, and there are best practices to follow by Unity by Oculus. There are very, very good tools out there and instructions on how to go about it.
David Mytton (19:03): Okay. How much is coding versus graphical design?
Elena Kokkinara (19:08): Well, I guess it depends on the experience in the use case. As I told you, for me, interaction and engagement are more important in order to create a good experience than very impressive graphics. But of course you go nowhere without a good artist, right. So it depends a little bit on what you're aiming for.
David Mytton (19:29): Right. So we've seen some examples of software engineers moving all of their development work into VR environments and there's a good blog post about someone who's doing this almost full time where they've got their editor in VR and they have loads of different windows open. You can kind of move around rather than having a big display or two displays. You could have eight or 16 in VR. What's your take on this approach?
Elena Kokkinara (19:58): There are people that want to escape reality and that's what VR is for. Some people have this need more than others. See the pandemic, and with all the lockdowns, people need it to be somewhere else in their house and VR helped. Or think of having to be in for a long time in an unpleasant space or very constrained space, like an airplane, you want something to escape this reality and VR it's super good for that, it's a good tool. But do you really want to be in VR long term in VR and they prefer reality from VR. I'm not sure, I prefer reality, to be honest. I could use VR for experiencing something special or learning something I couldn't learn in the real world, but I don't want to replace my reality for VR in the long term, let's say, right. In terms of the developers, yeah, I mean, maybe some people want to develop being by the beach for a few hours, but the entire day I'm doubtful they could even handle the tiredness in the eye and all these things.
David Mytton (21:09): Right. I suppose that's where graphical resolution becomes really important if you are dealing with text, which is what code is. If you've got a 4k monitor in front of you, you've got a high quality display and it can be, I suppose, quite challenging moving into a 3D world would rendering the quality that you need for the text.
Elena Kokkinara (21:27): Yeah. I don't think this would be really a problem soon. I mean, this will be solved if it's not already solved with the 8K headsets.
David Mytton (21:37): Okay. So it's more about just existing in the environment and how that is from a lifestyle perspective.
Elena Kokkinara (21:44): Yeah, definitely.
David Mytton (21:46): Yeah. Okay, and what about machine vision and image processing? Is that related to VR at all?
Elena Kokkinara (21:53): I think this is more relevant for AR so far, but the newest headsets, they come with depth cameras and see through cameras where they use them to blend, let's say reality with virtual reality. I can think of cool applications that you can do with these cameras using machine learning and image processing. I don't know, some sort of simulation of the real world by seeing the cameras in VR in a fun way, or they have been using it also for, let's say, recognizing obstacles in the real world, so you can avoid injuries and protect you somehow from bumping into things. I can think of other use cases also, but yeah, it wasn't ever a major technology to consider when working with VR, but it could be if you want to do fun applications.
David Mytton (22:45): Okay. What do you see the relationship with AR being? Do you say it's in competition with VR or the application's just very different.
David Mytton (23:30): Right. We've seen companies like Apple put a lot of time into their AR technologies and the APIs and everything over the last few years. Do you think that is the right direction? Is it constrained on a mobile device?
Elena Kokkinara (23:45): If Apple does it, it will become mainstream. So there is no way around it, to be honest and for sure they're going to do something very impressive and different than others. So, I mean, we're looking forward to it also.
David Mytton (24:04): Excellent. Before we wrap up, I have two lightning questions for you. So the first one is what interesting tools or dev tools are you playing around with at the moment?
Elena Kokkinara (24:15): We're playing around with some new headsets that to be honest, are very cool. There are some prototypes, they are ultra thin. They're more towards these sunglasses form factor that I said earlier. They're super cool. I mean they're prototypes still, but if the headsets go towards that direction, I think they would become much more attractive for the users.
David Mytton (24:47): And the innovation there is about how light it is and makes it just a lot easier to engage?
Elena Kokkinara (24:54): It's easier to wear, basically. It's easier to carry around.
David Mytton (24:59): Yeah. Then the second question is what is your current tech setup? What hardware and software are you using on a daily basis?
David Mytton (25:48): Excellent. Well, unfortunately that's all we've got time for. Thanks for joining us, Elena.
Elena Kokkinara (25:53): Thank you so much.
David Mytton (25:55): Thanks for listening to the Console Devtools podcast. Please let us know what you think on Twitter. I'm @davidmytton and you can follow @consoledotdev. Don't forget to subscribe and rate us in your podcast player. If you are playing around with or building any interesting dev tools, please get in touch. Our email is in the show notes. See you next time.
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