S1E5: From the lab to the factory with Johan van Stuijvesant Meijen and Clemens Dransfeld

I can imagine that for someone that's not familiar with composites, if you say I make airplanes out of hairs. Their reaction is probably it. We proposed a completely different way how to describe this composites. Composites is the word, or you call this fiber reinforced polymers. This disruptive way of describing these materials came by looking at a flock of birds flying back. When we saw a flock of birds, you know, stallings, for example, they moved, it's called a coherent motion. They moved as a flock because they moved together. And we figured out that the way how biologists describe this behavior, that we can translate this behavior to describe our material. This is Coffee with Martin, where aerospace conversations take off. In this episode, we go to the foundation of aviation, the materials. With more importantly, what it takes to turn an idea into something that actually works in the real world. How do you go from microscopic fibers to structures that carry people across the globe? I'm joined today by Clayman Stransfeld. He's a full professor within the department of aerospace structures and materials, with a strong focus on manufacturing. Together with Joann from Stuyves on Mayan, a young robotic engineer, he works at the Tudel Field Lab of Robotics, some Excel. Together we explore composites, manufacturing technologies and the reality of scaling innovation beyond the lab. Because in aviation, the real challenge isn't just inventing something new, it's making sure the world is ready to use it. Let's get into the conversation. So welcome, Joann and Clayman's to the podcast. Thank you. And my first question is always to my guest is what is your favorite cup of coffee? Oh, should I go first? Yeah, first. Yeah, but it's definitely not to the one at work. I'm sorry, but no, definitely the one I make myself in the morning with my mocha pot. I buy the beans from the coffee shop that you want open to roast beans. Nice, I didn't know that. Yeah, yeah, yeah, I go there once or two weeks. And just have my little ritual in the morning. So pour over coffee. No, it's there with the mocha pot. A mocha pot, okay. I grind the beans and then mocha pot. For you, Clayman? Well, the only coffee machine I have is a BL80, the one which is screwed together. Yeah. And this goes back from a time where lived in Italy. But actually my favorite coffee, I just had a flashback, is when I lived in Italy, you work in an office somewhere. And then you typically go down the street around the corner in a cafe, you stand, you don't sit down. And you have an espresso, you chat, and watch out and you walk back. That is in a way the idea of my favorite coffee. Yeah. And did it happen already in the Netherlands that you have your coffee like that? No. No. No, it's a culture-based. Yeah, it's a culture-based. So thanks for being here. My second question is, okay, if you're standing at that coffee machine at the TU Delft, and someone who approached you and said, hey, you are, or Clayman, what do you do? Can you explain that in one sentence? Ooh, in one sentence. It would definitely depend on who is asking, but I would say I'm trying to develop a technology to build the aircraft of the future. Okay. Not that. Sounds cool. I think it's cool. Yeah. And you, Clayman? Yeah, my answer is, tiny a little bit longer, but basically I work with composites. Composites are carbon fibers embedded in a polymer very strong and light materials. But these fibers are seven micron in diameter. So ten times thinner than a human hair. And my work is, how do I make out of such a thin fiber and then time aircraft? What are all the steps involved? That is my field of work. I can imagine that for someone that's not familiar with composites. If you say I make airplanes out of hairs, their reaction is probably what. So my first question is to get the deeper into the topic is, how do you stay on the edge of innovation in your own field? Well, particularly in my case, so Clayman's here gave a very broad answer of what he does. I'm a bit more specific because I'm just working on one technology. And then basically my way to push to the edge of innovation is try to push this technology to the highest level that you can achieve before it's being used in aircraft. And for this, if I really look at how I do this on a day to day, sometimes I just have these moments in which I just go to the lab and I do experiments a bit out of feeling and I try to just do the things I never did before. But for which I have this engineering sense that tells me you should try this because this might give you a innovative result and you might find out new things about the technology. What's that? I'm curious about that engineering feeling as you said. What's that? It's a bit of a. For me, sometimes it really feels like a gut feeling. I don't know, in the past months, you maybe did a bunch of experiments. And in some experiments, you observed some results of which you think, "Hey, there's something happening there, but you never really studied that particularly." So there's maybe this one parameter that in the machine that you can change. And one time, sometimes even by accident, you change a parameter or you forgot to turn it off, turn something on. And it has an effect. And so then you see that, "Hey, wait a second, there's something there." And then my engineering sense says, "Okay, maybe if I change that parameter this way, that way." That sounds like a happy feeling at that moment. Do you celebrate that? It's more actually so that when things stagnate a little bit with the results, then it can affect actually my mood a little bit sometimes. So I could enter the weekend a bit, not with a bad mood, but a little bit grumpy. Like, "Oh, did it manage to do this?" So then if I have one of these moments in which I get a result that I don't know where suddenly turns out to push innovation in that technology, then it just positively affects my mood a lot. And actually, for the past three months, I don't know what's happening, but I'm entering the weekend always in every mood. Always happy. Good things are going very well. Happy feeling. Yeah. We're going to later talk about the technology itself, but for you, Clamans, how do you stay on top of the innovation in your field of work? I think I stay on top of the innovation by looking at every other field, except my field. So I really like to be inspired to analogies by really looking at 360 degrees. Sometimes, for example, so I work with composites with these fine fibers and need to be aligned and consolidated. And so you find similar structures elsewhere in nature, for example. You find, for example, in system biology, people think about how to describe things, you know, for their world, whereas we can use them also in our domain. So I really like to go in completely, you know, tension fields, medical science, biology, art, anything philosophy, you know, to be inspired. And do you have like an example in the tip of your tongue that happened recently or what? Yeah, one example, for example, we proposed a completely different way how to describe these composites. Composites is the word, are you called this fiber reinforced polymers. Distrapped a way of describing these materials came by looking at a flock of birds flying by. And we saw like basically a flock of birds, you know, stallings, for example, they move, it's called in a coherent motion. They move as a flock because they move together. And that is like an unexpected connection analogy, but that proved so novel that other people start picking this up now. When was this? Or this was maybe three, four years ago? Okay. That's nice. There's proof coming around back to you again that the flock of birds is a, this is an analogy which you would normally not make and we were not actively looking at it. But yeah, the connections come sometimes the connections are very far outside of the main. And if you look at, because I know what you do, you do a lot of research on the tape line, that's machine, right? Okay, maybe go a bit more into depth about the technology and the machine and the research you do. So in this journey from a single thin fiber to an entire aircraft, you have to make intermediate products. And one of the first intermediate products nowadays is that you make a tape. A tape is a unique direction alignment of fibers, which is provided with its polymer matrix. Maybe it's a good drink, though. - Polymer matrix. - Yeah, polymer is basically the polymer matrix. So you have these very, very strong fibers. And the polymer matrix is like a liquid kind of something like a honey that you can melt and push between the fibers. And then that polymer, then a room temperature is hard and keeps the fibers together. And together between the fibers and the polymer, you get this ultra strong material. These are really high properties. - Yeah. And what do you do on the machine? - Yeah, and so basically you have to go from the fibers and the polymer. You have to make this intermediate product or you can call it a starting product. And we work really on the science how to make these starting products. And then with these tapes, later on, colleagues, like Johan, you know, they will put it on a robot and use the robot to lay down in a complex shape, for example. - Yeah. - But our work is really the performance of the material is hidden in the intricacies of that starting product. - Yeah. - And so we worry a lot about or investigate how do we have to align fibers, impregnate them, make sure there's a thin as possible, as homogeneous as possible. That the fibers are well aligned or whether they are maybe a bit moving around, should they, should they not, should the fibers be distributed evenly into that polymer. - And what is the biggest challenge in that research? - It's controlling the material at all scales. Maybe to explain that, you know, the larger scale is maybe the aircraft component, which is like our curved shell with ribs. - Yeah. - But then if you go down, the shell itself is composed of multiple layers, and the layers are made out of those tapes. And within the tapes, you have the fibers, which are seemingly all aligned, but not really. And we know, also from previous researchers and previous research, that very small differences in that alignment at a micrometer scale, have a microscopic effect on the performance, you know, can basically make the difference between, it's a great material, or it's a very bad material. - And I'm curious, because we do that in a lab environment, in a controlled environment, we do a lot of research on that specific material, but we're not selling the material to an aircraft manufacturer. - Yeah, what's the next step, are you in contact with the industry, or does the industry visit us, or how does that process look like? - Yeah, our product is not the tape, or we don't have a webshop, we can order our tape. - Our product is the knowledge, basically. So, so we, on our equipment, we figure out how it can be done, and that can lead to multiple outputs. - Here, we explore material configurations that nobody has done before, or we do research on, for example, what is more and more important, circular materials, we re-process recycled materials, or we make materials with our configuration. For example, we work on ultra-thin tapes that have special properties, you know, and we basically, what we do, we try to develop the manufacturing technology to make this product, we try to prove the performance, you know, how is the relation between processing and performance. - So, this knowledge, we do, then, often trigger the interests of industry, and the industry can be anybody from a carbon fiber manufacturer, or an aircraft producer, who say, "Could you work with us together, we would like to understand that better." - Yeah, it's good to know. - And, Joann, let's talk about, let's say, your technology. - Sure. - You do cool stuff with robots? - Yes, yes, yes. - Can you explain the listener what you do? - Okay, I'll try to not get too nerdy on it. Basically, the technology I'm working on is very broadly seen, it's a welding machine, so, clements, just explain how it's very busy with creating these tapes, the material itself. And, you use that material to create panels or components. Sometimes, in an aircraft, well, aircraft for nowadays is built out of a lot, a lot, a lot of different components, and these components need to be joined together. So, like an example, which is very simply the wing attached to the fuselage, to the barrel. But also, at the smaller scale, you have little overlaps that you need to join together. And, in our technology, we're trying to weld two parts together. The thing is, there's a catch to this, because the reason why we try to do this is because there's this material that we are also strongly pushing for in the Netherlands. Those are composites with carbon fibers, so these very thin hairs, where the polymer matrix is a specific type of polymer matrix. And that's a thermoplastic. So, thermoplastic, I don't know if you would want to ring the bell. - Let's do it. - Thermoplastic composites. The type of plastic that you can melt and reconsole it against. For example, the plastic bottles at the supermarkets, those you can melt, and then they become cool down, they become hard again. But there's other types of plastics that are more like they go through a chemical process. So, yeah, those are called, usually epoxies. I don't know if people have heard about epoxies. - Let's ring the. - Epoxy. - I'm going to have to ring the bell many times. - Well, that's the type of polymers, thermosets. And there you have, it's a two component plastic. So, when the two components are mixed, it goes through a chemical process and then it becomes hard. And then when it's hard, you cannot melt it. - It stays like that. - You can compare it like making a pancake. First, it's liquid, then you provide heat, and then it's solid. - It's solid, and it will stay like this, under the heated plastic. - Yeah, yeah, yeah, then the only, if you heat it up again, you're only going to burn it. Or you're not going to make it into the liquid pancake. - But you. - So, you're in a bombing technique for aircraft, but do you know how it's being done right now? What's the current status of technology? How do they connect aircraft parts? - So, this is also a bit where I was trying to go. So, right now, the materials that are used in aircraft are not this fiber with the thermoplastic matrix. It's either aluminium or thermosets, so the epoxies. And these materials you cannot weld. So, right now, they're using techniques like riveting. So, it's very simply said, like bolts, to join parts together. Or they're using adhesives. Or, in case of the epoxies structures, you can also just. Before they go through the full chemical reaction, you can put two parts together that you want to join. And while they're in contact, they continue going through that chemical process. And then they become like one piece. You call that co-curing. But now, because we see this potential for this thermoplastic composites, this new material that, in the Netherlands, we're actually trying to push for a lot. In order to use the material, you need to have techniques to process the material and to assemble parts made of this material. And one of the advantages of this material that you can melt it and consolidate it again, so that would be like welding. So, we are developing a technique to weld these materials. So, you mentioned the robots. So, actually, I myself don't work a lot on the robot, but I work on the part that is attached to the robots. That is trying to make contact with two components made of this material. And it tries to generate heat where the two components touch each other so that they melt. And you apply pressure and then you can create a very strong bond between the two parts. Then my question pops to mind is, why should we use a robot then? If the technique of bonding is separate from the robotic technology? That's a good question. So, first of all, a human would never be able to apply the force. That we need in our technology, so to have an idea, the experiments I did the other day, we were applying forces of close to 4000 Newton. And that would be equivalent to 400 kilos, more or less. So, we press onto our parts with 400 kilos. And well, to get a bit of a. context of my technology continues ultrasonic welding. What happens is we have a sort of hammer that makes contact with the parts and it vibrates at an ultrasonic frequency, 20,000 times per second it vibrates with a very small amplitude so you rarely see it. 20,000 times per second. Yes, yes, yes, 20,000 times per second. The hammer, well it makes contact, it's like vibrating. That causes a lot of friction and when you have friction 20,000 times per second, they might be rubbing your hands against each other 20,000 times per second while you could make fire on your hands. And yeah, this hammer is applying force of like together with other components of 400 kilos. We as humans cannot do that. So that's why you need big machines to apply these forces and then why specifically a robot. So we use a very large robotic arm that can also do very complex movements. So you could also just create a simple structure where you connect a cylinder and apply the force but the moment you want a weld curved components. So in airplanes the shapes are need to be aerodynamic. So you're going to find a lot of curved curved paths in an airplane in order to go over such paths you need a machine that can do complex movements. And if you look at from the state of art today, you're working on that material compared to when it's are we going to apply it and then aircraft factory. When are we continuous, it's only welding aircraft parts together. What's your idea? Oh yeah. Well, hopefully, hopefully very soon. I would say so in the aircraft industry is a bit conservative because I mean of course we we're talking about the lives of people we need to know what we're doing. So the path of developing a technology you need to really demonstrate that your product is safe and that you can deliver the quality that they want. But maybe we could be talking about between now and 10 years to be applying it on structures that are not primary. So a primary structure in an airplane is a structure that really carries a lot of load. So in the wings for example and we could be already applying the technology maybe on structures which are not primary. So that if if they would break it would not mean that the aircraft crashes into the ocean. And if if you look at these carbon fiber tape exclaments it's already been used right in making wing structures. Increasingly yeah. Thermal plastic tapes are slowly slowly being used more and more. But also it's a bit the same story. I mean the aerospace industry is a risk adverse industry which we when we sit on a plane we're all very happy about that. But that also means that basically you first try a new technology and a really small part if it falls off airplane will still fly. And and maybe you put it on a bigger part and if it this falls up it will fly not so good but it can still make it. And then only when you're over the years you accumulate experience and you're really sure you haven't overlooked anything. This is then where you move slowly to very large structures. And but for and in thermoplastic composites originally the people people were working with fabrics. So a fabric is really like a textile like the clothing we wear. And these fabrics were then impregnated into thermoplastic that this was called organo sheets. And they said it is advantage first the fibers are like on in the weave pattern going up and down they're underlating so they are not straight therefore they are not strong. And the other thing is imagine you it's like making a clothing you buy a roll of textile and you cut out the pattern and 50% is waste. And now if you assemble imagine you assemble you close out of UD tapes you know you put next to each other there is hardly any waste and the fibers are straight and strong. So and you can apply it with a robot like similar robots like you are working on. And so it is better in performance less waste and high performance higher level of automation. So you're only putting the fibers there where the structure needs exact that's interesting. And it's way easier to tailor to locally put more fibers where I need them. But it is still in a way even that there are companies like given an example GKN Fokker who are pioneers in introducing thermoplastic composites to the market. It is still for example the vision of making an entire fuselage barrel out of thermoplastic composites really large or making a wing cover you know like the upper lower part of a wing like a 20 meter 20 meter part in one shot. This is still a daring venture and even that on paper the technology exists but this is a major risk also in equipment machinery to go this way. And eventually it will come. And one of you said earlier that the Nellens is let's say big in thermoplastic composites. It's a unique setting. KK you tell me a bit more about that. Yeah I think it is a really I mean I look at it someone I only live here maybe eight years now. So I was always looking with envy looking at it from abroad. But it is a unique setting of universities and companies emerging out of these university environments where they had developed very strong entrepreneurial vision with a few key people who said we think this is the next thing and we put all our bets on that. And because of that material manufacturers emerged in the Nellens who were really pioneering like these fibers and tapes and fabrics also originally then companies emerged who were focusing on how do I turn the semi finished or the starting material into a shape. Other companies were focusing on how do I design the machinery to make the parts. Other companies were focusing or I need simulation software for this forming process. How do I do that? And so basically in the Nellens for being a smaller country there is a unique density of competences academic and industrial which you find in this concentration you felt I would say nowhere in the world. It's really a unique setting. And this you know once you have reached that critical threshold it becomes of itself propelling you know then people work together now each other they do more they make more progress through collaboration and having good collaboration partners you know and this propels itself more and then the outside world is going to look at you as the expert. And people come more and more to work together. And do you know what choice is determined such a market entrance for a new material, a new part. It's not really trial error right? So it's how who do you have to convince that your technology is superb. For this I have to quote someone. I have to quote Anto Fringa, a Jika and Fokker who is one of the pioneers in really introducing thermoplastic Iro structures. And he said like well you have to dare when you are a smaller player on a global scale and Nellens is a small player you have to dare to go a different way. And also what he said what resonated very well with me is you have on the other side on the customer side on the OEM side you need one person who believes in you. Because ultimately it's a bit it's about trust and taking a risk and you can do all qualification programs and tests and everything you know you can but still when you have proven everything and you've proven it works you know the prices competitive the performance every you check all the boxes still someone has to say yes I'm going to do it but this means that we are going in a completely different journey until compared to what we have done until now. Yeah so it's a non-technical variable. Yeah it's a non-technical it's a really it's a human factor in spite of all the technology it's a human factor at the end. Yeah that is decisive to make it you know from to push it from the lab into an industrial application. So we are academics right so we work in academia. How do we work together with the industry because it's it's a different world right so we're not commercial as tudel and then you can forcress to make money out of a product so how does that how does that knowledge come I would say it's very simple just a listen and understand okay basically just I mean both sides listen to each other I think industry partners good industry partners are very open and curious you know what are you doing why are you doing it and and and we as academics should be very interested in understanding industry, why do you take this decision? And especially when these are non-technical decisions, what led you to do this? And try to understand and by understanding each other, you can put yourself into other people's roles and that may create the decisive shift, maybe in your research. 'Cause I'm gonna address my problem differently. And Johan, how do you take your industry partner along in your work? - I work in this research center called SumXL. - Maybe we should. - Hey, what is SumXL? Smart, advanced, manufacturing, XL. So we are a research center or field lab. I've heard many names for it. But basically just a very big space where technology that was started in the universities when the faculty, so actually SumXL is right across the road from the faculty of aerospace engineering. And technologies that originated in the faculty of aerospace engineering, we also have other technologies that may be originated somewhere else, maybe mechanical engineering. But a lot from aerospace engineering, these technologies where they saw potential of, hey, this can actually be applied in industry and maybe we need to push a bit more to get this actually out into industry. Because often in the faculty, if you have maybe someone doing a PhD on a topic, that's the person needs to write papers, needs to write a lot of articles. SumXL is a bit more the spot where we can also do a lot of research on technology. But. - More applied? - More applied. So we want to make it work. We don't necessarily want to understand the effect of this parameter on this. So that's also where I said before, sometimes I just go to the lab and I just try things out and see what works because I got to make it work in the end. - Yeah. And I think it's also because you're doing, you're at the edge of invention, right? So you cannot read the book of. - No, I wish I could ask chat DPD. - Yeah. The computer says, no, I think if you type that in. - Yeah. - So you need the industry as input for your. - Yeah, yeah. So this is indeed the industry. They provide us sort of the requirements. So I want to have this machine, this welding machine being used in airplanes, maybe also in other industries. We're also looking into that a bit now. But it needs to perform a certain task to build aircraft. - When did you graduate last year? - Only two years ago. - I think it was exactly two years ago. - Exactly. - And the 20th of March of. - Yeah, but you worked for a university, right? For the field of some cell. Why did you not choose to go into industry? - So I did my master thesis at Semiccel working on the technology that I work on now. Once you actually get to experience the freedom that you get from doing research on a technology that you have to push forward, it's hard to let go. So I have other friends that got jobs. They all went to Amsterdam. And I don't see them using their creativity a lot. Or actually, I think the concept of freedom in work that is something that I have a lot in. And I think people in universities have a lot. People trust, they trust you. They know that you are, or they hope that you are a bright mind. They put you to do a task and they hope that something will come out. But no one is gonna tell you how to do engineering. Exactly, no one is gonna tell you, yeah, you have to do. You have an end goal and you have to get to that end goal. But the path you can quite tune yourself how you go on that path. - They trust you for you being you. - Yeah. - And then you take that responsibility to the next level. So when my thesis supervisor from Somexel, which is now my colleague, he proposed me to continue working at Somexel, it really felt like I felt valued for what I did before. So he really appreciated the way I approached the technology. - Yeah. - Yeah, the little innovation that I could bring to it. And I feel like I'm still very valued. So it's a very rewarding environment. When things go well, it's really, it's like this little adrenaline in your body. That's like, oh, yes. - And I think Leman's you're a professor at the effective aerospace. I don't think you woke up someday saying, I want to become a professor. - No, well, maybe you know it, but I remember at I think at the end of my high school, I think my father asked me, so what do you want to do? And I said, well, everything except becoming an academic. (laughing) - So you're kidding. - So I think something went wrong along the way. - Yeah. - But it is maybe a journey, you know, like I had a very industrial mindset. I really went, well, when, no, actually it was not the end of high school, it was at the end of my studies. My motivation to learn skills, you know, studied material science and later industry design was I wanted to make things, you know, I wanted to have the skills to make things. And I made many things, you know, designed many products, developed many processes that were put into practice. But then behind that satisfaction of being a creator or a maker in a way, below that layer grew a little plant and that plant is called curiosity. And that grew bigger and bigger and bigger. And actually through making things, you can satisfy your curiosity also. But at some point it kind of took over, you know, and now they are after having a long industrial career of products on the market, which I can say, well, I designed those. Now I take more satisfaction out of really wanting to understand why things work and, yeah, I'm just on a pure knowledge. - Yeah. And maybe general question for you, both if you look at the airspace industry, we are all talking about hydrogen flying, electrical flying. What do you see in that new ways of flying or the future of flight in, let's say, 10, 15 years because you're in top of the innovation, let's say invention, right? You're in the front row. So you must know what's going on there. If you're opinion about it. - It's complicated. I think we will see a whole array of solutions with different life spans appearing concurrently, you know, right now. I mean, for example, on the base layer, but very important, it's a whole development, which is not at all about materials or anything. It's about sustainable aviation fuels, you know. When you make sustainable aviation fuels, you can take all existing aircraft, fuel them up, done, basically. - So with the current technology, you can change. - Yeah, already with the current technology, you can change, but that is only part of the answer, you know? And then I think we will see maybe emerging as an emerging plant. We may see electric flight for short range connections. Because it seems in spite of you think batteries are heavy, but as an aerospace engineer, you're an aerospace engineer, you may know an aircraft power a doxel must not be light to fly efficient. An aircraft can be, it needs to be light to take off, but once it flies, it can be actually heavy. So battery for short range, it may be a solution. And I think the whole thing is like hydrogen, propelled flight for long range distance, where you need to have the hydrogen, you need to cool it down until it becomes liquid. So at cryogenic temperatures, and you need to maintain it in that state, and that is a big deal, you know, in all aspects, probably the most disruptive one in terms of technologies. And that may come even later, and then maybe more in the long distance flights. So we will have a layering of solutions and systems. And in the same way, we will also see, especially the new, I mean, for all new sustainable aviation fuels, for electricity and for hydrogen, compared to the growth of electric cars, you know, you need the whole infrastructure. You know, you need airports that have charging stations, airports that have system-reviation-flute airports, where you can refuel hydrogen, you know, that must be produced somewhere. So only having the product is only a part of the solution, but when will the infrastructure be there? And that is a bit like a. - A chicken and egg. - Chicken and egg that goes slowly, you know, like with electric cars. - Yeah, a new year-own, how do you see? - Well, actually, a few. - So what I was thinking, the first thing that popped to my mind when you asked this question is that, So within the aerospace industry, actually, if you look at the faculty, it already splits up in a lot of disciplines. So we are mostly working on the structures. But you can change so many things. You can also change the whole aerodynamics. So you can, instead of having a traditional airplane, you can have like a flying V. But for these things to happen, all the different disciplines needs to advance. And my contribution from my side is I'm going to try to make the structures as light as possible. And hopefully, so with the technology that I work on, you could potentially make the aircraft lighter. And then possibly allow for electric or hydrogen, or maybe it actually allows you to change the full shape of the aircraft because you can manufacture in a different way. So it's a combination of things. I'll try to reason your answer. But so, manufactibility is very important. I think also for you both in your research. When do you take that manufactibility into account while making your tapes or controlling the robot? Well, when do we take it into account? When does it say aircraft manufactures? No, you because I think you make a piece of the puzzle where you can take that to, let's say, an arbor that makes the aircraft. Or is it not that important? Well, I mean, the whole reason why my technology exists is because of the good properties of the material that I work with in terms of manufactureability. I think it's intrinsic. While you're working, it is driven by the idea of manufacturing. And maybe the close off this round of podcasts is I've prepared three questions. There's two options and you have to choose. So, Klemens, first you. I'm not flying at all in the future or I want to fly consciously. I want to fly consciously. For you, you own? Very good question. Actually, I'm in the process of buying a van so that I can travel more just around your electric van. Yeah, it should be electric then. That's true. Very good question. So, I actually see myself in the situation that's very often when I have to take flights. It's because my friends want me to take flights and I have to say no to plans. But in the end, I cannot say no, it's very difficult. So, I would like to also answer with I would fly consciously. Second question is that if you look at technology, do you think the technology to progress is already here? Do we have it in our heads? Or, no, we need more research. We need more time to develop the technology. I think it is already there in our minds in different places, in different disciplines. And we need to put the puzzle together and putting it together is not just putting it together, but you need to add a layer of knowledge to know how to put it together. I totally agree. I feel like always with technology, it exists. It's there. Maybe not with a physical product that you can buy, but it is there. And you just need to, the courageous people that see it and actually make it into something. And you need time and invest. Last question. Do you prefer having the material in your hands or the machine in your hands? I want both. It's very easy. I could not compromise in between. Because the machine makes the material. So, especially in the field of composites, you cannot separate between the material and the path. And the machine, that is what in my whole career keeps on fascinating me. The machine makes the material and the part at the same time. Nice. And this is like doing magic all the time. So it keeps on intriguing me. So I need both. Sorry. I give you a wild card. Not to choose. Yeah. Well, I actually love playing around with my machine. So I would say the machine, but the problem is if I don't have material, then there's nothing to do with the machine. Understand. But I would choose the machine. Thank you guys. Thank you both for this nice. Thank you so much for organizing. Thank you so much for the invite. I think it's a great initiative. Innovation doesn't end when something works in the lab. That's where the real challenge begins. Because the impact only happens when the world is ready to adopt it. Thanks for listening to Coffee with Martin and tune in for the next episode.