Where can I pass slides? This one slice back and forth is hello everyone. Thank you for having me here. Also like the curation of the of the slides was is is very nice because I feel like the work I’m doing is a is like if the four previous presentation had a child. And yeah, we’re going to talk a little bit more about creasing and you’ll see all the share visions I have with many of the previous talks.

0:39 My name is Alfonso Parra. I’m a PhD student at the MIT Center for Bits and Atoms. Sadly, I’m not graduated yet. But I’m having a blast. So, I’m procrastinating that part. But I eventually have to graduate. I’m not sure yet. Maybe May. U this is at MIT. The director is Neil Hersianfeld and as you can see I am very interested on folding mostly large scale stuff mostly non-paper materials although folding paper is a is is a very sketch process right and today I want to share with you what I consider very important is about like how a combination of folding and discretetly assembly can enable the realization of architected materials across three different scale that we will go from millimeters 2 meters to the dozens of meters.

1:25 And allow me to start from the back like why discretely assembly and discreetly assembly. This audience is very much educated on mechanical metamaterials we will go super fast. Mechanical metamaterials those man-made materials that shown properties that are impossible to find in nature. And most of them follow cellular solid approaches. We saw in the keynote yesterday how since the atoms to monolithic materials geometry is governing with local rules global properties and you don’t need to look that back from cellular solids you can start there Lorna Gibson opened a whole field of research about cellular solids her main conclusions that that was that these kind of materials in which geometry plays a huge role their material properties mostly depend of of course in the consent material but geometry plays a huge part of it as well which is great news for us as we have more tools in our toolbox to do fun stuff but of course there’s always a caveat and the problem is that the challenges and manufacture them at scale and this is important at scale because of of course additive manufacturing came with a premise that I’m going to solve complexity which is a partial lie as it’s solving complexity in your volume printing but we have bigger problems than this and in my I’ve in my lab we like to see additive manufacturing as an as an analog process because of all the information is encoded on how do you displace material or remove material not in the material.

3:04 So as a to push back that we like to see our approaches as digital materials and in case you might be confused let’s make together an exercise which I think it’s pretty fun. Let’s watch kid building Legos and then you realize that the stuff they make is very straight and then you ask the same kid to draw a straight line and it’s a little bit not straight.

3:31 And the reason of this is because Lego is fundamentally digital because of the the the the Lego block has tiny building tiny local geometries that provides something that is extremely important which is error correction in every step and that is the fundamental soul of digital. Digital is not about boolean. Digital is about error correction. How unreliable sources of information can give you reliable outputs. And so that’s make that digital is a key feature for scaling.

4:09 Also there’s no trash in a Lego room which that’s fascinating. Everything is a block. That’s like the main core and you can also reconfigure. So following those same premises in my lab, Kevin Chung generated the lightest stiff stiffest lattice done since today. We’ve also published on discretely assembly discretly assembled mechanical metamaterials showing that we provide a family of faces and you can reconfigure on them to make materials with homogeneous properties.

4:43 Then we have also been exploring about like let’s get rid of monolithic properties. Let’s go let’s let’s dive in to the anisrop piece. So, we show how we can make one afternoon robots that are able to swim or to fly with camber morphing. But well, so I hope I have convinced you about the discrete assembly part and I want to try to convince you about why folding because of it’s another key part of my thesis.

5:17 All the previous elements I’ve showed you are beam based materials like cellular solids that are satisfied by linking beams. And you know research is not quite about saying that plate lises outperform beam based materials at same density specifically on stiffness and strength. The reason for that is this beautiful paper is shows to me like the best example for for for to to have a rationality for this in this paper Thomas Jon let’s take a look to the cell here to the right at the end of the day a lattice is no more than just like your topological order of connectivity right we have those two cell are the same just six points the one in the left is joined by a beam the one in the right is joined by a plate.

6:07 If we equalize the area of that cross-section and extrude it, we have same volume. And also cross-section of pose are analogly similar to for second moment of inertia. So if we crush them, what is h going to happen is the cell in the right is going to have two elements working and the cell in the left is going to have one element working which is going to give us for free twice stiffness and strength.

6:32 And if you look at from a manufacturing perspective folding is intrinsically a 2D process. 2D process are extremely important just because of in very for example in very demanding industries are the only one that are available to provide us rate u but if you look from a car manufacturing perspective for example it consumes the 23% of the total amount of energy and to me that’s wild like because of like if you would design just something that unfolds you will need way less energy resources to satisfy the shape that you’re designing to.

7:17 So I think we can come to a conclusion that as as Julia was saying as well folding provides you with efficiency your stock now is can come from MacMaster you don’t need to order fancy powders u and it has huge potential to be accessible to build in almost every place that doesn’t need to have like extremely technological capabilities. So that is why I combine folding and discrety assembly for achieve architectural materials across three different engineering scales and I’ll show you more work starting from the smaller and bulk solar materials this work is about okay the premise for this work are two one is that I want to take the cheapest MacMaster steel I have fold it and show that we can compete eat in the ashby plot with very fancy 3D printers, optimizes, lices stuff.

8:14 This later we will see that Toyota was collaborating with us for for this work and implement trying to implement in the motoachi plant. And the second origin of like why I’m fascinated about this problem is because this paper of Robert Orici that talks about the natural conflicts between strength and toughness and I think this is a way to try to ticklish this problem. I started by taking semi-p periodic latises cubic center cubic oct face center cubic octahedra vertical next octahedra you can see this lattice in both ways doesn’t matter I pick octets because I know I can fold them so I make pyramids of it the analytic folding equations for things with axial symmetry are quasi trivial just like and this is the key part of my thesis.

9:12 Like in my thesis, geometry is the description, the mechanism and the method of a structure. So if I know every state of the unit cell, I can just like helping to fold. So these are just like PLA 3D printed molds. I have samples of these later you want to play with them. But this is 301 stainless steel 0.3 mm. We can fold 302 420 aitic martensitic doesn’t matter and which I consider that this is very important because of like this has a huge potential to simplify the supply chain of your manufacturing process like a stamping process on a car might have like up to 60 alloys but that is because of material has a budget of strain and we’re using the budget of that strain to satisfy shape.

9:57 These type of processes don’t use that budget they give you shape for free. I made an army of them. I assembled them and and then like that’s me. And then Toyota told me like I read your paper and I did 2,000 and I was like holy. I went to the Moto Mashi plant. It was pretty nice. And I showed that the assembly process is uni actual so has a beautiful potential for automation.

10:26 I made a family of them to show that like also like the beauty part of this can be that my thickness is almost irrelevant for my manufacturing process. Kind of same molds will give me different compression behaviors. I show here cost without my cost to be fair because I’m a in like we say in the lab grad student with tweezers are free. But what I’m trying to say is that it only has 20 bucks of steel from MacMaster.

11:00 And we all know that MacMaster is not cheap. We show that I love MacMaster by the way disclaimer. Don’t get me confused. I show that if you will try to simulate this will be a nightmare. So why don’t we simulate one apply 3D predictive boundary conditions and and and just keep going which we do that and as me the my engineer side love projections I don’t want to have one simulation this conference has been about like one engineer simulating a thousand this is exactly that because later for some project you’re going to see later I might need like 600s of megapascal at 0.015 and 015 relative density.

11:43 So I get my candidate B4 and has some folding patterns. I folded that assembly assemble and we show that it reliably simulates. So the goal was to get cheap steel and make it perform well. So we’re in a pretty sweet spot in the ashb plot and let me walk to you here. These are scaling laws. Different cellular properties will scale depending of if they’re being based, blade base.

12:14 Even if you put the wor the worst scaling law, we’re still scaling pretty well into the region that Rachel I think was commenting. This is for stiffness. This is man-made lightweight materials. And there was an island there. And so I I put there a gift for the people to grab. This is for strength and this was some of the uses that was to protect that green sysmometer.

12:44 Sismometer really needs to be protected because they need to measure very tiny movement but they need this project need to be launched from an airplane which is you know not a good idea. So the foam will protect everything. And something that fascinates me as well is that if you go dynamic okay 13 minutes good if you go dynamic and you are into a crash event the plot of your force is that you’re going to get a peak force then you’re going to have a plateau and then you’re going to have compactation.

13:13 What kills you is the peak force. In this work I show that I can control peak forces and I can control plateau. Compactation is for free and that’s actually kind of good. So I’m working on dynamic crack initiator crack initiators and again all this brings is brought by 3D printing PLA and then folding steel and assembly. So that’s one of the we ah I’m I’m activating the videos every time I click.

My bad. We jump into a larger scale. Let’s go to the meters. This project started because Airbus came to us and told us that they want to they want us to make the horizontal tail plane of the A320 but now morphing at scale one to one. And I was working previously on the beam based thermoxuded materials and I started to increase the beam thickness up to the point that this was not a cellular solid anymore which is to me funny.

14:13 So I said like okay I’m going to fold it and it works. So we wrote this project about kigamic corugation strong modular and program of plate lises where I take the mirror fold and I expand it. I tend to expand all my folds. I show analytical solutions for everything and of course we discretly assemble them. But the caveat of like the oh sorry and it show like for example the static performance of this is pretty good.

14:47 60 kontons I check on check GPT has an analog approximation to be six to seven horses. So it performs really well and weighs 250 grams by the way. But the key part the thing I love is that if you break locally the maxwell stability for criteria and you go from stretch dominated to bending dominated you induce bending stiffness and isopropies and that’s fantastic because now you can make robots.

15:18 So we made a bunch of tentacles and this kind of robots as well with this work. And the last of the projects I will show you will be on the architectural scale. One of the benefit of being a grad student is that people tell you you want to come this summer to work with me in this lab and you say yes. So Tommo told me to go to University of Tokyo last summer and of course they say yes.

15:46 And I was playing with mostly run rest dissolations. And it’s a huge beautiful candidate to go to the architectural scale. This work is done with Ricardo Fosi Ruper Malik Moachi and Neil. And the key part of this concept is like if you take a tripod a run tripod and you make a funky unit cell by mirroring and twisting half of its period when you assemble on these three main properties you made effectively a structure that is an hexagonal woven beams that’s very pretty and you preserve your constant second moment of inertia and you can then numerical approximating for surfaces this is the first time I’m numerical approximating I need to acknowledge it So you can make there has a huge potential for the architectural level where with tiny triangles we can go again from local geometry to very big local geometry to make stuff like this or to make stuff like this.

16:49 So here the the the key part I think is that as a designer now you also have control of your cross-section which is directly bending stiffness. So, so like you keep embedding information local information in your unit cell at same cost of manufacturing. And the last project I will show is just a a deviation of my work just for fun with friends. I apply for some grant to make an exhibition of our work.

17:19 They say that if you’re going to make it pretty, make it red. If you’re going to make it red, make it shiny. And if you’re going to make it shiny, make it big. And I really don’t like red. So I I I went very big and very shiny. And these are the works like I’ve been using tools from friends like Clara Mundilova my own tools and then showing that folding and discreetly assembly can realize architectural scale structures in almost an afternoon.

17:49 So we designed this ball is an echosahedron by the way in a weird way. Then this is my favorite close polyhedra the jinosahedron. And this is some 7 m tower. Everything is aluminum. So if anything of this resonated to you and you happen to come to Boston, I’m teaching a workshop with a bunch of circular origami friends on November 16 and 17 in my shop. Which we have a lot of machines.

18:24 It’s going to be very fun. I would recommend you if you can assist. I don’t know how many people has subscribed. We have a limit of 15 people. But it’s going to be fun. So thank you so much. I’ll see you around. To see the full recording of this and previous presentations as well as information about future CDF events, visit CDFAM.com.