Latest / Mechanical Engineering Made Simple / (#101) Fixing Teslas and Evolving NASA Parts
Transcript
- 0:00Welcome back design junkies, to Mechanical Engineering Made
- 0:02Simple. If you enjoy the podcast, show
- 0:05your support with a like a follow or comment.
- 0:07It's free for you but means the world to us.
- 0:10Let's keep leveling up together. It is great to be back.
- 0:12So today we are looking at a well, a massive shift in how
- 0:17things are made. And look, I know we hear game
- 0:19changers every other week in this industry all the time.
- 0:22But today, I don't mean a small change or, you know, a new
- 0:25button in SolidWorks. I mean a fundamental rewrite of
- 0:29the rulebook. Yeah, total paradigm shift.
- 0:31Exactly. We aren't just talking about CAD
- 0:33drawings anymore. We're talking about systems that
- 0:36evolve geometry the way nature evolves bones, right?
- 0:39Cars that can physically fix themselves while sitting in your
- 0:43driveway and the AI Co pilots making it all happen.
- 0:46That's right. And our mission for this deep
- 0:48dive is really to walk through that story, the story of the
- 0:51modern digital engineer. OK, we're going to trace this
- 0:54chronologically, so it all makes sense.
- 0:56We'll start with the birth of the digital twin at NASA.
- 0:59Back in the space race. Back in the space race, then
- 1:02we'll move into generative design where the AI actually
- 1:06takes the wheel. And finally we have to do this.
- 1:08We look at the risks. The scary stuff.
- 1:11The scary stuff What happens when these incredibly powerful
- 1:14tools get into the wrong hands? I was reading through the source
- 1:18material you sent and I have to say there were some serious aha
- 1:22moments. Specifically, a NASA bracket
- 1:25that looks like it belongs in an alien autopsy and a ransomware
- 1:29concept that learns how to play you like a video game.
- 1:32But OK, before we get there, let's start with the Foundation,
- 1:35the Digital Twin. The digital twin.
- 1:37It's a buzzword we hear constantly.
- 1:39Right. And usually when I hear Digital
- 1:41Twin, I just think of a really high fidelity 3D model, you
- 1:44know, a fancy assembly and KTS spinning on a screen.
- 1:48But you're telling me that's too shallow?
- 1:50Way too shallow. If you just have a 3D model, you
- 1:52have a digital shadow. Not a twin, a shadow.
- 1:54OK, a true digital twin or DT, is a synchronized link with a
- 1:59physical object. Imagine a turbine in a factory
- 2:03or a car on the road. The DT uses data from embedded
- 2:06sensors to simulate the the real time status of that object.
- 2:11So it's not just the geometry, it's the state.
- 2:14Exactly. If the physical object heats up,
- 2:16the twin heats up. In the simulation, if the
- 2:18physical object starts vibrating at, say, 40 Hertz, the twin
- 2:22vibrates at 40 Hertz. It's a living mirror.
- 2:25That distinction is crucial. That is the difference between a
- 2:27photograph and a live video feed.
- 2:29Perfect analogy. But where did this start?
- 2:31Because I'm guessing we didn't have IoT sensors back in the
- 2:34day. We did not, but we did have the
- 2:36Apollo project, and this is the origin story.
- 2:39OK, NASA had this massive logistical problem.
- 2:42I mean, once you launch a vehicle into space you can't
- 2:45exactly pop the hood to check on a rattling noise.
- 2:48No physical access. Zero.
- 2:50So essentially built two of them, two space vehicles, one
- 2:53went on the mission and one stayed right here on Earth.
- 2:56The twin. That sounds incredibly
- 2:58expensive, but I guess it was necessary.
- 3:00So if an oxygen tank explodes on Apollo 13.
- 3:03You test the fix on the Earth twin first.
- 3:06You see if it works before you tell the astronauts 1,000,000
- 3:09miles away to try it. It mirrored operations to allow
- 3:14for troubleshooting. That was the grandfather of the
- 3:17digital twin. High stakes, high cost, and all
- 3:20manually synchronized. Exactly.
- 3:22OK, that's NASA. They have the budget for two
- 3:23spaceships. But how does this Fast forward
- 3:27to today? How does this concept look in my
- 3:30driveway because I don't have a second car in a lab mirroring my
- 3:34commute? No but a server does and the
- 3:36best examle right now is Tesla secifically the model right?
- 3:39Tesla uses digital twins to design their cars but the magic
- 3:43haens because they Kee them connected.
- 3:45The cars are constantly talking to a remote center and this is
- 3:48more than just GPS or Spotify updates.
- 3:51Much, much further. So here's a specific story that
- 3:53really highlights the power of this Back in 2013, there were
- 3:56reports of three Model S cars experiencing burnouts.
- 4:00Burnouts. So fires.
- 4:01Essentially overheating issues that led to fires.
- 4:03Yes, yes. Now in the old world of
- 4:04automotive engineering, what happens next?
- 4:06That is a massive physical recall.
- 4:09You're sending letters. People are driving the
- 4:11dealerships waiting for hours. It's the logistics nightmare.
- 4:14And APR disaster. But Tesla used the digital twin
- 4:18approach. They analyzed the data streaming
- 4:21from the cars, the digital twins of the entire fleet.
- 4:25So what did they find? They realized the problem wasn't
- 4:28a defective part necessarily. It was an issue they could fix
- 4:31by changing the suspension clearance at highway speeds and
- 4:36altering the charging settings. So the car was riding too low
- 4:39and hitting debris on the road. Partly, yeah.
- 4:41So they pushed an update over the air.
- 4:43They effectively fixed a hardware vulnerability with
- 4:46software. The problem was solved without
- 4:48the owners ever having to open the hood.
- 4:50That is wild. I mean, it just changes the
- 4:53entire economics of maintenance. It does, and it lets you do what
- 4:56we call predictive maintenance. You can re engineer the life of
- 4:59a product like doing fatigue analysis on an aircraft wing
- 5:03without destroying the physical object.
- 5:04You're simulating the stress on the digital version to save the
- 5:07physical one. Precisely.
- 5:08It's a game changer. It's like having a voodoo doll,
- 5:11but you use it to heal the person instead of hurt them.
- 5:14That is actually a surprisingly good analogy.
- 5:17I might have to steal that one. Feel free.
- 5:20OK, so that's monitoring things. That's keeping an eye on what
- 5:23already exists. But the sources you sent over
- 5:26suggest an even bigger shift is happening in how we create
- 5:29things. This brings us to generative
- 5:32design. This is where the role of the
- 5:34engineer really starts to change.
- 5:36Traditionally, engineering is well, a human sits down, stares
- 5:40at a blank screen and draws a shape.
- 5:42I think this bracket should be a square with a hole in it.
- 5:45Exactly. Then they run a simulation to
- 5:47see if it breaks. Right iteration one it breaks
- 5:49you make it thicker iteration 2. It's manual trial and error in
- 5:53generative design. The human doesn't draw the shape
- 5:55at all. So what do they do?
- 5:56Just ask the computer nicely? Yeah, please make a bracket.
- 5:59Almost. They define the requirements.
- 6:01They tell the computer I need a part that can hold this much
- 6:04load, uses this material, and very importantly stays out of
- 6:08these specific zones. And then the AI generates the
- 6:13shape. It sounds a bit like those AI
- 6:15art generators everyone's playing with now.
- 6:17Is the exact same concept. One of our sources uses the
- 6:20analogy of Dolly. You type in an armchair in the
- 6:24shape of an avocado, and it creates it.
- 6:26It explores the latent space of possible images to find one that
- 6:31matches your text. An avocado armchair.
- 6:34I would sit in that. Sounds comfortable, but in
- 6:36engineering, we're not making avocado chairs, we're making
- 6:39titanium space parts. The stakes are a lot higher
- 6:41because physics doesn't negotiate.
- 6:43Good point. So give us a walkthrough of a
- 6:45success story. I'm a little skeptical.
- 6:47Is the AI actually finding better solutions or just weird
- 6:51ones? Let's look at the NASA Goddard
- 6:53Space Flight Center. They have this process called
- 6:56evolve structures. Okay, they were building
- 6:58something called the Excite tip tilt bracket for a balloon
- 7:01mission The. Excite Bracket sounds intense.
- 7:04What were the constraints? It had to hold a sensor short,
- 7:06but the main challenge was shock.
- 7:08It had to survive a parachute landing.
- 7:10We're talking about A10G vertical load. 10 GS.
- 7:13So if that bracket weighs a pound, it suddenly feels like 10
- 7:16lbs instantly. Right.
- 7:18And it couldn't block the light paths for the instrument.
- 7:22So NASA set up a showdown Man versus machine.
- 7:26I love a good rivalry O the human team.
- 7:29An expert designer and a structural analyst.
- 7:32People at the top of their game. And the AI team.
- 7:34One engineer and his only job was to encode the requirements
- 7:38into the software. OK, So what happened?
- 7:40The human team worked for two days.
- 7:42They went through four different iterations.
- 7:44They struggled to balance the stiffness and the weight.
- 7:46And AI team it. Took about 30 minutes of human
- 7:49time to set up and then the AI just ran for an hour.
- 7:52So it's faster. I mean, that's not surprising,
- 7:55but was the design actually better?
- 7:57Significantly better, right? The human designs were either
- 8:00too heavy or in their final attempt, just unmanufacturable.
- 8:04It looked good in CAD, but you couldn't actually build it.
- 8:07The AI design however, well, it looked weird.
- 8:10It looked organic. It looked bone like.
- 8:13When you say bone like what do you mean?
- 8:14It looked like the inside of a femur, all these messy,
- 8:16intricate structures. And that happens because the
- 8:19algorithms used topology optimization.
- 8:22They just remove material that isn't carrying stress, which is
- 8:25exactly how nature evolves bones.
- 8:28It's a principle called Wolf's law.
- 8:30If a part of your bone isn't bearing a load, your body
- 8:32dissolves it to save energy. And if it's under high stress,
- 8:36it adds more material there. Exactly.
- 8:39So the AI is basically simulating millions of years of
- 8:42evolution in an hour. Doesn't care about looking
- 8:45pretty or geometric, it only cares about the load path.
- 8:49And what were the final stats on that?
- 8:50The AI part was three times stiffer and significantly
- 8:54lighter than the best human attempt.
- 8:56Plus it was designed for digital manufacturing, so they can send
- 8:59the file straight to a 3D printer.
- 9:01That's incredible. You're talking about development
- 9:03time dropping from months down to days, and you get a better
- 9:06part. It's not just about speed, it's
- 9:08about breaking out of human bias.
- 9:10Yeah, we like straight lines and 90° angles.
- 9:13Nature doesn't. But this raises a tough
- 9:15question. If the AI is so good, faster,
- 9:18stronger, lighter, why do we need the humans at all?
- 9:22Why not just hit print on a car? Because of something called the
- 9:25complexity trap. OK, let's unpack that.
- 9:27What's the complexity trap? Think about a modern car.
- 9:29It's not just an engine of wheels anymore.
- 9:31It has 80s advanced driver assistance systems.
- 9:34It has heated seats, infotainment, hundreds of
- 9:37sensors. All of that needs power and
- 9:40data. Which means wires.
- 9:41Miles of wires. The Siemens source highlights
- 9:44this perfectly. The wiring harnesses in modern
- 9:47vehicles are massive. They're incredibly intricate.
- 9:50You simply cannot draw every single wire manually anymore.
- 9:54So you reach a point where the human brain is the bottleneck.
- 9:58It is the bottlenecks. You need something called wiring
- 10:00synthesis. You set automated rules that
- 10:02generate thousands of connections and splices.
- 10:04But here's the catch. And this brings us to this idea
- 10:07of next Gen. AI.
- 10:09And how is next Gen. AI different from say, the chat
- 10:12bot I used to write emails? Well, current AI, like those
- 10:15chat bots, is based on large language models.
- 10:18Yeah, they're great at text and images, but they they struggle
- 10:21with physics. They hallucinate.
- 10:23What does a hallucination look like in an engineering context?
- 10:26It. Looks like the AI is suggesting
- 10:28a material that doesn't exist or designing a bolt that goes
- 10:31straight through a fuel tank, right?
- 10:32Not good. You don't want an AI
- 10:34hallucinating the brakes on your car.
- 10:36Definitely not. So we need constraints.
- 10:38We need first principles. NextGen AI is designed to adhere
- 10:42to physics and manufacturing constraints.
- 10:44It has to be grounded in reality.
- 10:46So where does the engineer fit in this new world if the AI is
- 10:50generating the geometry and checking the physics?
- 10:53The role shifts. The engineer becomes a copilot.
- 10:56They stop doing the rote tasks like verifying every single bolt
- 10:59or drawing every wire. Instead, they define the
- 11:02problems. They become the architect of
- 11:04constraints. Architect of constraints.
- 11:07I like that title, sounds important.
- 11:08It is. It's a human centric approach
- 11:10approach. The AI points the engineer in
- 11:12the right direction, but the human has to be there to stop
- 11:15the AI from designing something unsafe.
- 11:17You need that oversight. So the AI answers the question,
- 11:20but the human has to ask the right question.
- 11:22That's a perfect way to put. It OK, so the engineer is the
- 11:25pilot, AI is the copilot. But looking at the report on the
- 11:29malicious use of AI, there's a flip side.
- 11:31If this AI is so powerful for building things, surely it's
- 11:35just as powerful for breaking them.
- 11:37Unfortunately, yes. This is the dark side of digital
- 11:40engineering. The same algorithms that
- 11:42optimize a bracket for strength can optimize an attack for
- 11:45destruction. And what does that look like in
- 11:47practice? Well, think about how the AI
- 11:50designed that NASA bracket. It explored thousands of options
- 11:53to find the optimal shape. Hackers can use that same logic
- 11:57for automation of vulnerability discovery.
- 11:59Meaning just as the off ago AI found interesting moves in the
- 12:03game of Go that no human had ever thought of, right, an AI
- 12:06can scour software code to find interesting vulnerabilities that
- 12:10no human security analyst ever noticed.
- 12:12So it finds the open window that nobody knew was there.
- 12:16Then it exploits it. Yeah, the report outlines A
- 12:18hypothetical scenario they call Wanna laugh.
- 12:21Sound like a bad joke? A very expensive one.
- 12:24Imagine a ransomware that uses AI V8 I to constantly rewrite
- 12:27its own code. Usually security comanies find a
- 12:31pattern, a signature and write a atch to stop malware.
- 12:34OK, but if the malware learns and evolves like a video game
- 12:38player, it can bypass those patches instantly.
- 12:41It evolves faster than the defense.
- 12:42It's polymorphic. That is the fear.
- 12:45And it's not just software. We're talking about physical
- 12:47threats too. Drones.
- 12:48I've seen the videos of drone swarms that look like a flock of
- 12:51birds. It's terrifying.
- 12:52And it's a very hard thing to stop.
- 12:55In 2018, there was an assassination attempt on the
- 12:57president of Venezuela using drones.
- 13:00In 2019, there was that attack on the Saudi Aramco oil
- 13:03facilities. And that was a swarm, right?
- 13:05Yes, a swarm of 25 drones operating in unison.
- 13:09When you combine that with AI navigation, you get a weapon
- 13:12that is very cheap but very destructive.
- 13:16The swarm just follows simple rules.
- 13:17Don't hit your neighbor. Fly toward the target, but the
- 13:20group behavior is incredibly hard to defend.
- 13:23A guess. And there is something in the
- 13:24notes about face morphing that sounded like it was straight out
- 13:27of a spy novel. It's a serious identity threat.
- 13:30You take two faces, say yours and mine, and you merge them
- 13:33into one photo. It looks enough like me to pass
- 13:36a human guard, but enough like you to fool the passport control
- 13:40AI. So one passport could work for
- 13:41two different people. Exactly.
- 13:43It tricks the border security AI.
- 13:45The take away here is that as we build these digital twins and
- 13:48use AI to design our world, we are increasing the attack
- 13:52surface. So we need AI fighting AI.
- 13:54We do. We need active countermeasures.
- 13:56We can't rely on human speed anymore.
- 13:58Before we wrap up, I just want to touch on the how.
- 14:01We've talked about AI evolving brackets and learning
- 14:03vulnerabilities, but strictly speaking, how does a machine
- 14:07actually do that? What's the math behind the
- 14:09magic? It's actually surprisingly
- 14:12intuitive. It's based on trial and error,
- 14:15which is a lot like reinforcement learning.
- 14:17Think of a SOAP bubble. OK, I'm picturing a bubble.
- 14:19Wand, if you dip a wireframe into soapy water, the film
- 14:23naturally forms a shape, right? It doesn't know math, it doesn't
- 14:26have ACPU, but it naturally finds the shape with the minimum
- 14:29surface area. It optimizes itself to the
- 14:32lowest energy state. It solves the physics problem
- 14:34just by existing, right? Now, in AI, we use a strategy
- 14:38that's often compared to a bacterium.
- 14:40There's this biological concept called run and twiddle.
- 14:42Run and twiddle, yeah. If a bacterium is moving towards
- 14:46food, so if life is getting better, it keeps running
- 14:49straight. If life gets worse, if the
- 14:51chemical signal gets weaker, it stops and twiddles.
- 14:54It just moves randomly until it finds a better direction.
- 14:56That's. Actually a really good life
- 14:58philosophy. If things are going well, keep
- 15:00going. If not, shake things up.
- 15:03It is, and that is essentially what these neural networks are
- 15:05doing is a process called gradient descent.
- 15:08They run a simulation. If the stress on the bracket is
- 15:11high, that's bad. So they twiddled the design
- 15:14They. Try something new.
- 15:15Right. If the stress goes down, that's
- 15:16good. So they keep going in that
- 15:18direction. They're just minimizing the
- 15:20error to evolve the perfect part.
- 15:22So that NASA bracket is basically just a very smart
- 15:25metallic soap bubble. In a mathematical sense, yes,
- 15:28it's finding the path of least resistance.
- 15:30So what does this all mean for our listeners?
- 15:32I mean, we've gone from NASA's twin spaceships keeping
- 15:35astronauts safe to AI that grows parts like bones, and now we're
- 15:40facing the need to stay one step ahead of the wanna laughs of the
- 15:43world. I think the big conclusion is
- 15:45that the future isn't about AI replacing engineers, it's about
- 15:49engineers evolving, levelling up.
- 15:52Exactly. The value of an engineer is
- 15:55shifting. It's moving from the act of
- 15:58drawing up the manual task of creating geometry to the act of
- 16:02understanding. So the engineer of the future is
- 16:05that architect of constraints. That's it.
- 16:08The better you can describe the problem, the loads, the heat,
- 16:12the materials, the better the AI can solve it.
- 16:14It's not about having the answers anymore, it's about
- 16:16asking the right questions. Spot on.
- 16:19If you could define the constraints, you control the
- 16:21output. That is a lot to think about.
- 16:23Whether you're designing A spacecraft or just trying to
- 16:25organize your wiring harness, the tools are changing the game.
- 16:28Absolutely. If you haven't already, get over
- 16:30to our YouTube channel Mechanical Engineering Made
- 16:33Simple, where we post hands on how to videos, visual
- 16:36breakdowns, and practical engineering walkthroughs.
- 16:38You can actually actually use a family that solves together
- 16:40stays together. Thanks for listening.