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dCLCp t1_j8mgiul wrote

I would have appreciated if they highlighted some of the downsides in this article. There is always a downside. Just off the top of my head, we know that these "thousands of bespoke parts" work, but we don't know how they work precisely. They can make predictions and hopefully nothing breaks in a way we don't understand (because it works in a way we don't understand) but as projects become increasingly sophisticated with more and more moving parts and separate contracts layers of siloed bureaucracy... eventually the people that designed part A will make something that interacts with part L in a way that they didn't predict because the parts weren't designed in concert from the ground up. They were designed separately and artificially. The parameters were known but parameters change. Mistakes also happen. How resilient will these parts be when suprises happen?

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youarenotyourstuff t1_j8motvt wrote

I agree that downsides should be discussed along with benefits.

I disagree that we don’t know how they work. Part of the process of generating these designs is defining the interfaces to other parts, the loads and the pass/fail criteria. You literally have to define how it works to the algorithm to get the design in the first place.

If you get those things wrong, even classically designed parts can fail. Garbage in yields garbage out.

This is also the reason for validation. Validation often finds unanticipated or misunderstood interactions and manufacturing defects. Which is why it’s needed regardless of design method.

And if a part fails, then you know something in the process (design or manufacturing) is flawed and you chase down the root cause, find an effective solution and correct the process that produced the issue.

Basically, it’s all standard engineering practices for bespoke designs. It’s not easy, but it’s nothing new.

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dCLCp t1_j8mr1nk wrote

What do you think are the downsides?

Someone else mentioned standards. It's impossible to standardize anything when everything is bespoke. What else?

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youarenotyourstuff t1_j8mtm65 wrote

A big one is that designing with this process means at every step you are highly dependent on complex software modeling. Instead of using well known design rules to develop your design, you have to run a sophisticated algorithm that probably needs a hefty amount of compute power. Then you have to run FEA on literally every part, again needing lots of resources. That kind of software isn’t cheap and neither are the computer clusters.

Also, you have to put a lot of effort into defining your requirements very precisely and uncovering hidden requirements. For example, if you need a lot of strength in a part do you need that in both directions or only one? If you only need strength in one direction the best solution might be a steel cable, but I don’t know if there algorithms would consider that.

There’s also part integration. Things have to be designed for manufacturing and service (part tolerance stack up, order of operations, tool and hand clearances, etc.)

You also have to carefully consider your validation and what assumptions it makes about the parts that might no longer be true.

In the end, generative design is probably only worth the effort for specific parts or even portions of those parts, not the whole product.

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____Theo____ t1_j8ny30p wrote

But all of these considerations are also in play when you design something without the gen algo. This is just engineering lol

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youarenotyourstuff t1_j8o99hm wrote

Yeah that’s my point. All the normal engineering steps apply for sure. Just some of them are made more difficult due to a complex shape instead of a beam.

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Khaylain t1_j8n3fig wrote

There's also a problem with adding on stuff later. For example you have some brackets to hold something, one made classically with mostly square shapes, the other with this type.

Then you later need to add some way to attach another thing to the bracket. With the classic version there might be the option to just add some threaded holes and it's done, with the AI/topographical version you'll probably have to start "from scratch".

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C-D-W t1_j8myxi8 wrote

I disagree. We know exactly why they work because they are using Finite Element Analysis to test them, just like we would with any other part.

In fact, the neat part about this process is that they are basically using FEA in reverse to create them. So we're using math that we know works from zillions of different validations on traditional parts - and feeding that into an algorithm that just connects the load point dots in the most efficient way possible given certain constraints.

So I would say it's more reliable than you give it credit for.

But the biggest downside, and the reason you won't probably ever see this style of design used more widely is that manufacturability is a huge pain and/or expensive. Outside of 3D printing technology, these things are very hard to actually construct.

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dCLCp t1_j8mzagt wrote

Mmm yes thank you this is the type of input I was hoping for.

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t6jesse t1_j8mpkpx wrote

I think the AI is using the same software tools as humans are to analyze each iteration's strength - it's not thinking in some alien language. Also it's reacting to prompts and parameters set by humans. The only difference is it has the patience to brute-force every possible solution, whereas human engineers usually think in terms of what they've seen before.

I think all the issues you've laid out are issues that any large and sophisticated project would face, not specifically an Ai-powered one.

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dCLCp t1_j8mqus4 wrote

That's fine but the main thrust of my point (hence why I lead with it) is there ARE downsides. And they didn't discuss those which makes this article less good because I'd already heard about them doing this stuff. I knew it was being used, and while this article did elaborate more than some random scimag article I read 7 years ago that was talking in theoretical terms, it should have also elaborated more on the downsides because this type of writing is almost sensationalistic when that is the exact opposite that I want from science journalism. I want to know the whole truth.

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____Theo____ t1_j8nzeli wrote

I think your confusing this tool as some panacea where engineering input is no longer needed. It’s not automating the whole design process. It’s just a tool for one part of it, all the additional concerns you have mentioned are part of the engineering process. If you have AI start dictating the requirements, inputs, and validation then yea that gets scary. This is just a design tool

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dCLCp t1_j8obwc2 wrote

I think you are missing my point entirely which is merely that we deserve to know more.

That's it. Everything else is just me speculating as an example and your own assumptions about ME based on those speculations while ignoring the only thing I cared about.

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____Theo____ t1_j8opcx2 wrote

I hear what your saying. I should mention that I am a mechanical engineer. And to directly address your original post. Your concerned that it’s not clear that the part is designed to appropriately handle the loads or that conditions may change and it may no longer work properly.

The part design can only be robust enough to handle the conditions it is designed for. Getting the right requirements is the first step of the design process. If the requirements change the part would need to be totally re evaluated. This would be true wether it’s designed traditionally or not.

Both methods evaluate the part in the same way. The same simulation of the part would be done (fea). I don’t see any point where the engineer would not be sure if the part can withstand load conditions given. There’s no hidden magic.

TL/DR Wether it’s an organic shape or traditional design. They are evaluated for suitability/ strength the same way. And in both cases the design is only as good as the requirements given. If requirements change, designs always need to be re-evaluated no matter the method the geometry was formed.

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Arbiter51x t1_j8mifz1 wrote

I think that major problem is nothing in these designs can be certified to be built to any form of technical standard or building code.

We see this problem in the nuclear industry all the time- its very difficult to advance new building codes when you are locked into ASME / ASTM and 10CFR because they all rely on underlying codes (B31, B51) which are built on decades old, proven design. Everything in Nuclear is mission critical, and I would imagine it's the same in Space travel. High quality, proven design, based on established codes and known calculations to back them up. That is proper engineering design.

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youarenotyourstuff t1_j8mq5tb wrote

Aerospace is completely different to building design.

In aerospace designs are custom out of necessity due to each part being highly mass optimized, interdependent on other parts and having different design goals and trade offs from project to project. Also, each part is highly validated and inspected as well as painstakingly assembled in (usually) very clean environments. The exact safety factor of the product is well known and controlled to a low ratio.

In building design, designs are using either commodity parts or commodity materials that are produced too much less exacting precision, often made on site exposed to the elements. So design knows the exact safety factor isn’t known and needs to be large to make up for this. There’s also always human lives at risk.

So building design rightfully has to be very conservative, regulated and has no impetus to change quickly. Aerospace design has to be less prescriptive and less safe just to make it to orbit. That doesn’t mean there’s not a ton of very good engineering involved in both fields, it just means more design freedom for aerospace.

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Arbiter51x t1_j8mrazc wrote

Is it possible to do design validation for designs like in the article?

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C-D-W t1_j8my5am wrote

I think the idea that most parts aren't already bespoke is a misconception. Everything structural on a rocket or space craft is bespoke. Only built for that craft. Maybe only built a handful of times. So that part is nothing new.

Validation for these designs would be no different than anything else. Finite Element Analisys (FEA) would be used first to evaluate the structure and any changes required to meet the specification would be made before prototyping.

However, what's neat about these procedurally generated parts is that it basically is FEA in reverse. Instead of doing design iteration from idea to part - you just tell it the specification and it designs a part that meets that out of the gate.

The only real downside is that you're much more limited on manufacturability. Either it can't be made using traditional methods and requires 3D printing. Or maybe it can be made on a CNC milling machine but it requires a 7+ axis machine center and takes 100x longer to make. Which for some parts might actually be fine, but for others the added cost would never make sense.

Really interesting topic I'd say.

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youarenotyourstuff t1_j8mu4yq wrote

Yes. These designs are basically highly optimized, non-uniform load structures. You validate their load capability the same way you validate complex parts designed by humans: finite element analysis (FEA).

Edit: FEA is how you validate before your first prototype is made. You also CNC or 3D print a prototype and physically stress it just like any other part. Design validation is NOT just done on paper. It also is done on prototypes made using non-production equipment / tooling.

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r_a_d_ t1_j8mymq6 wrote

FEA is actually part of the generation process... It's basically iterating different designs and validating many times. So the output of the process is already at least FEA validated. You would then do all the additional validation that you would typically do on a classically designed part as well.

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Portmanteau_that t1_j8oxlc0 wrote

It's the same in the medical field as well. Extensive V&V for any 'new' device, even if it's based on predicate devices. I think a lot of laypeople aren't aware of the quality and regulatory requirements already in place for industries like these.

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J3SS1KURR t1_j8ooell wrote

I was about to say the article does mention it, but I went back and reread to confirm and realized I had used my own knowledge to supplement or something because yeah, they literally don't talk about the cons of this tech in the article at all. That's bad. I guess I understand why after looking at the type of the content the site produces, but it's still disingenuous when the crux of this problem right now is figuring out whether these designs will hold up at the microscopic/atomic level under the extreme temperature and pressure forces, states, and changes they'll be routinely subject to. Besides sending them up to test, there isn't currently a nice way to ensure the performance specs.

I think the tech itself is great. I'm also really fond of the innovations they've made with sound waves at Fabrisonic--for the longest time it seemed like magic because I couldn't wrap my mind around weaving sound waves into physically-real metals. After reading a couple research papers and going through the math/physics, I finally have a handle on it and how clever it is. It reminds me of the foundations of string theory. Both generative-design techs will undoubtedly lead to innovations and spin-off techs in other industries; biomedical being a primary branch.

I'm a biophysicist by title, but I have graduate degrees in astro/computational physics as well so this is definitely something I've been keen on. I'd love to ultimately get to work with the tech via collaboration or get something in my lab for student research if that's ever a possibility. It's a really cool next step to take that I think is brilliant. We already hijack so many natural processes in the lab (gene copying/tagging, medicines, plasmid-insertions etc.), that it makes sense to use a more biological process in the scaffolding of aerospace and rocket engineering as well.

The cons are extra important to pinpoint. Especially to the engineers, researchers, and scientists who are particularly interested in generative design. Finding ways to solve those problems are the very reasons some people even exist in these industries at all. I'm actually really impressed at the time scales they have this operating at. I'd be interested in seeing exactly what changes it comes up with on average in 2-4 hours period. That's an insane turnaround time. I was expecting changes on the level of days or weeks. Thus, I'm also curious about how the system is evolving and analyzing each generation. At this point I'm just rambling though, so I'll leave it at that. I agree, they should have outlined the key issues alongside the benefits.

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