 Thank you very much. I appreciate being here. It's a great event, as always. And it's my great pleasure now to introduce Andres Arrieta. He is one of our ME very successful associate professors. Andres got his BSME in 2006 from the University of Los Andes in Bogota, Colombia. And then a PhD in 2010 from the University of Bristol in the United Kingdom. Andres has been an exceptional scholar and researcher for us in the school and does most of his research at the Herig Labs, which is a lab very close to my heart. His research focuses on exploiting structural non-linearities to achieve intrinsic property and shape adaptability in engineering systems. His approach has resulted in very novel functionality of metamaterials, morphing wings, energy harvesting, and soft robotics. His research work has attracted significant funding from the National Science Foundation, Defense Advanced Research Project Agency like DARPA, and the Air Force Office of Scientific Research, as well as industrial sponsors, such as Anhorza Bush, like that one, as well as Ford Motor Company, among others. He has been very productive, lots of publications in journals, but in particular in articles in science, applied reviews letters, and ACS Nano. He also has been very active in going to conferences and publishing period conference paper, just what we expect from a professor of his stature. He has already mentored seven PhD students to completion, as well as 18 master students to completion, which is quite productive for this stage of the career. His most notable award today is the ASME Gary Anderson Early Achievement Award in 2018, as well as NSF Career Award. It's my very distinct pleasure to introduce Andres Ariadar. Thank you, Eckhart. Thanks everybody to be here. It's really a privilege to be able to talk about my journey to many of my mentors, some of the people I look after, to be able to, you know, as an aspiration to go in their footsteps, and also to talk to my students, which of course are the ones who have allowed me to be here. My talk is going to be a little bit different. I'm going to talk about my curiosity of discovering, and how this was the journey that I take to become a professor. So I wanted to make this relatively personal, and this was by choice, and it was a choice that I made because I'm relatively impersonal when I'm the university. So I wanted to show this side to my students and also to my colleagues, and what motivates me to be here. So my motivation started by looking at a KLM jumbo jet when I was two years old. So I remember these, we went on a trip and I heard all my life that I was, well, not all my life, when I was a kid for several years, I heard that I was repeating all the time where is my KLM jumbo jet, KLM jumbo jet, KLM blue jumbo jet. So somehow I really liked jumbo and I really like aircraft. And also when I was growing up, I had really a big privilege of having three grandparents that were looking after me, and in particular one who was living with me, and all the time feeding me with information. And some of the information was about science and about the solar system. So the first place where I started writing my name properly was an astronomy book about the solar system. And on that time, we had still nine planets. And of course, I'm very sad to say that I put it there on purpose to keep Pluto there. Now, of course, it's dwarf planets, so it was degraded. But anyways, or demoted, sorry, not degraded. These were things that I was really fascinated when I was a kid. And when I started thinking about what I wanted to be when I was an adult, I was fixated to become an aerospace engineer. But then I started to realize how life works. So I come from Columbia, and we didn't have, well, actually, there was one aerospace program in Columbia at the time. But I understood that it was probably not the best to follow. So I settled for mechanical engineering. And I took that choice because I knew that that was my surest path to be able to work on aerospace applications. So while I was growing, you know, this is the late 80s. Steel, the world was not globalized as it is now. So my parents, and in Columbia, it was hard to get Lego. So we had our own Colombian Lego, which is called Armotodo. And I was making spaceships that, to me, look like these. Unfortunately, I didn't have any pictures of them. But I remember they were quite nice to me. And I played all the time with them. And the interesting thing is that these things were made for architectural applications. So these started to form my thinking, I believe, in how can I connect and how can I use what is available to me to find the best path to achieving my goals. And my goal was to have a spaceship like this one. So then I used my Armotodos that were given for us as a gift to do buildings. Now, I'm going to make a big jump. I did go to Los Andes, and I'm extremely grateful for my education there. It was really thorough. And it really taught me some of the most important lessons that I carry with me, one of which is grit and being humble. So when I went to Los Andes, and he didn't have pictures of that, unfortunately, but I remember the speech of my head of department. He presented the department. He told us how the program was. And then he ended up, his speech, and there were some cake and some refreshments on the back of the room. And he said, OK, everybody, I wish you all the best. And I hope you enjoy the cake and the drinks, because this is the only gift you're going to have in the next five years. And I always tell this to my students, because it marked me. I understood what was needed to be successful in a place that was elite, because Los Andes is an elite university. And there was no gift. I assure you about that. And there were hard times, but it was really, really satisfying to be able to raise the level to the challenge and do the best that I could under those circumstances. And coming from a school in Colombia that is better known now than almost 21 years ago. No, sorry, that's when I started. When I left 15 years ago, it was hard to go to a place like the University of Bristol. And the story of how I ended up in Bristol is for another time. But I applied there, and my two advisors, in particular David Wag, believed in me and helped me to get a scholarship there. And it was really interesting. I don't want to talk too much about my research, but it was about these laminates that are changing shapes, just like slap bracelets. Or now these Microsoft mouse mice that some of you use. I know Stuart has it. I saw it yesterday. And I bought it myself, of course, a vice table mouse. It's something that I need to have. Anyways, I was working there on things that change shape and things that change shape dynamically. Because in my undergrad, I started to be very interested in dynamics and controls. And these allowed me to work on something that was close to my childhood dreams, which is aerospace applications. And at some point, my dream was to put these on a large aircraft, which is a little bit too much. But anyways, it kept me going for some time. Now, after my time at Bristol, I was very fortunate to meet Professor Peter Haggedon, which I know Arbind also knows. And there in Darmstadt, I deepened my knowledge in nonlinear dynamics and vibrations. And afterwards, I was extremely lucky to be able to go and work with Professor Paul Romani at ETH Zurich now on things that looked a little bit more to what I wanted to do with my childhood dreams. So we were able to develop some interesting applications on morphine structures and had my first opportunity to mentor students and meet other incredible human beings there. So then I started to think a little bit about what I wanted to do. And it took me some time. But from my astronomy and physics times and talking with my brother, I was very interested about fundamental phenomena. And I got involved or I started to play with these dome pattern sheets, which maybe some of your kids or some of you have on these puppet toys. And I wish I had patterned these before because they are really now everywhere. But anyways, it's still really interesting. So if any of you have played with these, you'll know that it's very interesting. These, it's called the metamaterials are reshaping when you start pressing on them and they have these hysteretic behavior that is very interesting. But when I started playing with these, I didn't know what these were leading me. Now, it led me to something that it's my second big point that I want to make. It's the interconnectedness that you find in everywhere in science and in life. So I had no idea that these dome pattern metamaterials when you press them and the reconfiguration was related to a very fundamental phenomenon called geometrical frustration, which is the inability for a lattice system or a system of interacting particles to minimize their interaction energies simultaneously. So there is classical example of a lattice made of triangles. So if these triangles are thought as, let's say, magnets and they want to be aligned antiferromagnetically, so they want to be one up and one down, you can arrange two of these guys in the triangle, but the three become frustrated and frustration. It's also an important part in our lives. It was in my life being a hyperactive kid. I gave a lot of frustration to my parents when they needed to go to school because I was, you know, messing around. And now it forms an interesting part of my life. I started finding frustration everywhere and in particular when you have all these lattices where these elements are interacting and are frustrated that cannot be minimized at the same time, you start having these states of degeneracy. And degeneracy essentially means that you have many possible states. And this happens in many different systems, starting by water eyes, colloids, magnetic systems, and even in some structures. And then what I was extremely happy to know is that these geometrical frustration and the many stable states that you find in these systems and in the sheets that I play with come from uncontrolled degeneracy. So this is a connection with the fundamentals. And when I teach my ME 274 class, ME 270, I try very hard to give my students a motivation of why it's important to learn the fundamentals. And I also try to tell them the connection between different fields. And when I started looking at this problem, I would have never guessed that it appears in condensed matter physics, in quantum physics with Goldstone bosons. And it was really fascinating for me to see all these connections. Where is this ball going to fall on this Mexican hat potential? This is the question. And it can fall and stop in any of those points. And this is what it's called degeneracy. You don't know where you're going to end up. In the same way that I didn't know that I was going to end up at Purdue. Very interesting how life pushes us and breaks symmetries. And we end up in some state at the end. So I want to tell you that it's very important to have your eyes open, to connect and to find interesting opportunities and look hard to reach out beyond your own comfort zone. Which is what I'm doing here. Because I'm no quantum mechanist. But it's been very interesting to draw some of these connections. And this has allowed us to start playing with these sheets and find order and find ways to control these geometrical frustration and create functional elements, like for example a robotic gripper, that it's a little bit more functional by this leveraging of the order in which these domes are inverted to reach one of these frustrated states that is more beneficial for a certain manipulation task. And to my great shock, one of the other nice works that I've done, and I'm very proud of it, was my connection with biology. And this is another point that I want to make. Being multidisciplinary in thinking, it's extremely important in the current world. So I was extremely lucky to get to know about the earwig wing. And it was serendipitous. I went to a breakfast with Professor Barry Trimmer, who was visiting us. I told him I work with multistable structures and said, oh, do you know the earwig? And he was like, I don't know what the earwig is. Do you know what the earwig is? Some of you may know it, right? I didn't know what... I actually knew what it was in Spanish, but I didn't know the name in English. Anyways, I started looking at the earwig wing, and so it happened that it has some specific properties that made it by stable, specifically that this wing can be looked as a four-facet origami system, but decreases spaces between the facets stretch. And this is what we found and led us to discover how the earwig wing unfolds and folds. This is an epi-simulation. What is extremely interesting is that these behavior of the stretching of the creases and the popping up and down that it leads these by stability, it's also connected to frustration. And you can see it by trying to put together in 3D tetrahedra. They will form six... Each vertex is going to come into a six... Each vertex will share six sides of a tetrahedron. And this is because this adds to 360. In Euclidean space, the addition of the angles when you share vertices need to add to 260. So if you try to put, for example, five tetrahedra together, there is going to be a missing angle. And this missing angle is the same missing angle that creates the popping up on the earwig and, again, my frustration appeared. So it's very interesting how, absolutely by luck, because I didn't know about this before I started studying, the main contributions of my work up until here were connected. It's really, really remarkable. This work, in particular, also highlights some of the other things that I think have really helped me to come here, which is I've really had the lock of being in different countries. I did my PhD in Great Britain, my postdoc in Germany, and was a group leader in Switzerland and seen all these different ways of doing the same thing by different peoples really helped me to understand diversity, appreciate diversity of approaches and diversity of backgrounds. And this has led me to put a lot of effort in helping with internationalization and collaborations as my contribution to my department and the college. So we have done some study abroad, outreach to minority engineers, and also I had the privilege of going with Ding Chiang to Colombia to try to enhance our collaborations with universities over there. Now, I think that I don't have too much time left for this, so I will go to the end. And is how I measure success? So I didn't have any metrics here because my metrics is to see my students having fun and also receive from my friends and my family their appreciation for my work. This is the metric I use and this is what really gives me and drives me every day. So these are just a collection of pictures of things that happened in my lab, our first conference in numbers, our first barbecue, my first doctoral hat. So these are traditions that I'm trying to bring from my time in Germany and Switzerland to my lab, my first hooding, first trip to Chicago and here are most of my students without whom I wouldn't be here and it's my privilege to be able to mentor them and share with them a little bit of the journey that brought me here. I also have to thank all my sponsors which of course help, not help us support us and allow us to do the wonderful things we do. And finally, I want to thank my family which had to deal with my frustrating behavior as I was growing up, particularly my granddad, he's going to turn 100 and won in a few days and his example really was consequential and fundamental to me being here. So thanks everybody and hopefully you can take some questions. Thank you Andres, that was truly wonderful, very informative, but also a little bit entertaining. Questions for Andres? Yes? Thank you, thank you for sharing the story, it's just a story, thank you so much. So this is Yu, I'm an assistant professor from industrial engineering, so my background is also robotics and mechanism design. So I saw this very interesting design, shape and morphine, shape programming. I wonder if you briefly comment about the challenges and the opportunities in shape and morphine in robot applications. Okay, yeah, this is really, really wonderful. So let me tell you how I got there. So I was working on morphine wings which tried to change the shape of an extremely optimized system, a wing structure, hyper light, and where the shape change, a little bit of bad shape destroys the behavior. So then I thought, okay, maybe I find a relatively simpler problem and then I started thinking about soft robotics or compliant robotics. Why is that? Because maybe it didn't have to be so lightweight, the shape didn't need to be so extremely precise and we started working on it. What I have learned is that, of course, this was not true. The challenges are equally hard. Now, what is very interesting about compliant robots for us is the opportunity to simplify their functioning by encoding properties into the structural system. And when I talk about properties functionality such as control and actuation. So I think that as engineers we naturally try to solve our problems by using techniques combining different types of systems and then using all our tools to make it work. But this begets complexity. And I think that this is one of the challenges for our time, particularly if we want to see robots everywhere. They cannot be complex and they cannot be very expensive. So an opportunity is how do you make robots more robust and simpler and how do you make them affordable such that they can be really deployed everywhere. And this is what's driving me in trying to come up with interesting properties that allow you to have encoded reconfiguration and coded controls. We call it encoded mechanologic to be able to have a simple input that by modulating it in time so this is connected to the order of the pressing of these meta sheets allow you to go to different types of final states. And I'm very happy to see that Milind was here. He helped me to understand that this is a type of higher level logic that it's just finite state machines type of logic which for me was relatively new when I started looking at it. But it gives an opportunity to simplify the system greatly. So I see that making affordable robotics it's a great opportunity and the challenge is how do you encode sufficient functionality to make it work. And we try to do that by simplifying the system as opposed to maybe make it more complex. Yeah, I'm Barrett Caldwell from Industrial Engineering. I want to ask you a very speculative question that actually goes back to your Colombian leg up. All right. There's been some recent work looking at the sound propagation on Mars looking at the speed of sound calculations from perseverance and ingenuity. Apparently, because of the nature of the atmosphere it's a biphase speed of sound with a transition in the acoustic range. If you are building a spacecraft or a structure on Mars do we have a geometric frustration problem if the speed of sound changes in a region that we might expect vibrations? I'm completely blown away by your question. I will be a fool if I try to respond technically. I don't know. I really don't know, but it's extremely interesting. It's extremely interesting. And this is serendipity happening as we speak. I cannot give an intelligent answer to your question but I'm going to make sure to find out what's going on there for sure. You'll hear from me. This is incredible. Any other questions? I'm sorry that I cannot give an answer. Of course, I expected Monk to have a question. I don't want to have any misconstruction that I'm not paying attention to this talk. By the way, great to see you again, I still vividly remember our journey together with a few other colleagues to Colombia and rest assured that while there are aeroastro-inspired mechanical engineers there are also a large number of mechanical-inspired aeroastro colleagues and students as well. On the topic of Colombia collaboration, just wondering, since the trip we took, which was three years ago or so, and visiting a few universities and tried to create a pipeline of exchange students and master and PhD students, how is it going and what more can we do? Well, that's a wonderful question, Dean Chang. I think we have got the momentum when we went. This was October 2019, and then we all know what happened in March, right? So everything came to a ground hold through the pandemic. But during the pandemic, right before the pandemic, I was at Los Andes, so I was very, you know, extremely lucky to recruit one of my students who's here, who's Juan Osorio, he's from Los Andes. And we have kept the connections. I met with my bachelor thesis advisor last December to try to reignite the exchange with students. Of course, we're hosting now Nicolás is here from Universidad Nacional on the Europe Sea program. But I think that we needed, we really need to reignite the connections. And what we discussed when I was last there is that we need to have an articulated sequence that allows also the professors from Columbia leverage the time that their students come here. And this is, for example, having six months here, then going to serve, and then they return in to finish their thesis there so that the publications can be done. And one of the ideas that we talked about was to have this symposium or small conference back in Columbia with the students that come here that do research such that we can showcase it to other students in the universities because they know about it, but the impact of having a symposium would allow us to have much more interest. So I think that this has not happened yet and hopefully we can try to do it for next year. So that's something that it's on my bucket list, although it's not really something that I have, it's an ultimate power to do, but I'm pushing for it. Thank you. I think we're almost out of time, right? Is that correct? Because my follow-on question to this is, you were recruiting from Columbia and me personally, I have a few students from Germany always floating around for some reason. But how do we expand this? How do we get others involved to really make it more of a global effort than just maybe on this personal relationship that we're trying to build? Yeah, this is the challenge. So I can tell you a sad story for us. When Juan applied, one of his colleagues, which was a mechanical engineer and he also did physics at the same time, which in Los Andes is not a mean feat, and got extremely high grades, applied to Purdue. His GPA, if you just translate it to percentage, was 91%. 91% in mechanical engineering in Los Andes is top 2% of the past 10 years, but nobody offered him an array here. He was in fluid dynamics. So the problem is that we have to go beyond to really learn the systems and maybe be more proactive in our graduate committees to have international professors that have this local knowledge to flag up these students more vigorously and be champions for them to come. So he is now in Denmark, right Juan? At DTU. It's a little loss for us, I think. So I think that we need to do more targeted recruiting. So what I was describing, have a symposium at the university. People will see our names. We have to have some faculty there to give weight to this symposium. And then when the opportunity comes, we need to grab them. And I think that this is maybe what happens. A little bit of lack of knowledge and we all are very busy, so it's very hard. But I think that there is... talent is really universal and we really need to look everywhere for it. Great. Thank you very much. I think I will close it out now. Avin, you want to have the last one. Thank you again, Andres, for a wonderful presentation. Andrew and Max, thank you. Thank you, Eckhart. And as Andres mentioned, he and I, academic brothers in a sense, coming from the same post-doc experience in Germany. So this is nice to see. Actually, I heard about Andres before he even applied here. My post-doc advisor at the time said, hey, you got to look out for Andres. I'm really glad it all worked out here. Well, this is the last celebrating or associate professor's event of this spring semester. So I'd like to thank all of you for participating. It's been a fantastic series. And, oh, yes, we have a lot of colleagues and friends online. So a big thanks to all of them as well for joining us. A big thanks to the committee, all the people who have organized this event, certainly to Ed and the AV team here, to Marcia, Maria and Amy, that have actually very successfully carried out these events. There's a lot of work. As you know, there's a lot of customized outreach to all the mentors, the special emails that go to specific individuals, asking them to apply, so a lot of work goes on. So please join me in thanking the honorees, as well as those who helped make this event possible. Thank you.