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Akin's Laws of Spacecraft Design (2011) [pdf]

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Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#71

Post by Nevermark »

pklausler wrote: post #45
nine_k wrote: post #42

Earlier quoted context omitted.

Imagine that you're a highly intellectual, highly technical, and highly responsible person in control of large sums of governmental or corporate money. You don't want to waste the money, you want stellar results (in spacecraft industry, maybe literally so). Would you assign a large sum of money to a group that cannot present their design clearly, neatly, and concisely? If they are struggling even with that, would you…

I think that Feynman was talking about preparing a freshman-level lecture for Caltech-standard freshmen, but maybe you have somebody else in mind.

I would say: You either don't understand your subject, or don't understand your audience, if you can't explain your subject to your audience, at the highest level they can understand, coherently.

The average person can understand anything ... at some level. Being able to match that level is positive evidence (but not proof) of competence.

Duality: Being unable to match that level is positive evidence (but not proof) of incompetence.

Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#73

Post by Nevermark »

ricksunny wrote: post #67

These are awesome. I took that capstone spacecraft design course at MIT in 2003, and can't recall encountering this list (based on the archive snapshot, he would have shifted on to UMD more than thirty years prior). The project was satellite-focused rather than launch vehicle, so maybe his instructions were imbued implicitly into the course? • Much of the design-conservative ethos permeates aerospace development. It'…

> I wonder how Elon / SpaceX folks would respond to these laws esp. #39 (avoid designing launch vehicles).

Perhaps, based on specific context, let the Law's vote!

> Law 11: Sometimes, the fastest way to get to the end is to throw everything out and start over.

> Law 16: The previous people [...] did not have a direct pipeline to the wisdom of the ages. There is therefore no reason to believe their analysis [was optimal].

> Law 31 (Mo's Law of Evolutionary Development): [...] understand the fundamental limitations of [the existing] technology/approach.

IMHO: Law 31 is the kicker. That triggers Law 11. With general support from Law 16.

Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#74

Post by JumpCrisscross »

Nevermark wrote: post #73
ricksunny wrote: post #67

These are awesome. I took that capstone spacecraft design course at MIT in 2003, and can't recall encountering this list (based on the archive snapshot, he would have shifted on to UMD more than thirty years prior). The project was satellite-focused rather than launch vehicle, so maybe his instructions were imbued implicitly into the course? • Much of the design-conservative ethos permeates aerospace development. It'…

> I wonder how Elon / SpaceX folks would respond to these laws esp. #39 (avoid designing launch vehicles). Perhaps, based on specific context, let the Law's vote! > Law 11: Sometimes, the fastest way to get to the end is to throw everything out and start over. > Law 16: The previous people [...] did not have a direct pipeline to the wisdom of the ages. There is therefore no reason to believe their analysis [was optim…

> > I wonder how Elon / SpaceX folks would respond to these laws esp. #39 (avoid designing launch vehicles)

SpaceX has designed 3 (four if you include Falcon 1) launch vehicles: Falcon 1, Falcon 9, Falcon Heavy and Starship. The first three run the same engine family and are arguably in the same vehicle family.

SpaceX has absolutely embraced avoiding designing new launch vehicles (and even major components) until the fundamental limitations of the existing approach are exceeded.

Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#75

Post by nine_k »

pklausler wrote: post #45
nine_k wrote: post #42

Earlier quoted context omitted.

Imagine that you're a highly intellectual, highly technical, and highly responsible person in control of large sums of governmental or corporate money. You don't want to waste the money, you want stellar results (in spacecraft industry, maybe literally so). Would you assign a large sum of money to a group that cannot present their design clearly, neatly, and concisely? If they are struggling even with that, would you…

I think that Feynman was talking about preparing a freshman-level lecture for Caltech-standard freshmen, but maybe you have somebody else in mind.

I think if you understand something really well (anything: the law of gravity, the Curry-Howard isomorphism, electrolytic dissociation, general relativity,...), you can find a bunch of comparisons, or metaphors, or other ways to explain it so that an interested five-years-old will get a rough idea. A very rough idea indeed, but one that could allow them to ask qualitatively reasonable questions, and that forms an intuition which helps during a real study.

Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#76

Post by userulluipeste »

nine_k wrote: post #42
barishnamazov wrote: post #10

Law 20 seems to express the state of most startups these days: > "A bad design with a good presentation is doomed eventually. A good design with a bad presentation is doomed immediately."

Imagine that you're a highly intellectual, highly technical, and highly responsible person in control of large sums of governmental or corporate money. You don't want to waste the money, you want stellar results (in spacecraft industry, maybe literally so). Would you assign a large sum of money to a group that cannot present their design clearly, neatly, and concisely? If they are struggling even with that, would you…

What often happens next is, another party comes up in the middle to manage the interaction between both of you (with the proper bump in the ask price), because there's not only so many decision makers looking for neat presentations and whatnot but also there's only so many teams willing to do the actual work.

Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#77

Post by CamperBob2 »

pjdesno wrote: post #40

> "Trellis coded modulation got this rate up to 50 kilobaud by the 1990s" Not quite, and an interesting story that fits these engineering maxims better than you might think. An analog channel with the bandwidth and SNR characteristics of a landline phone line has (IIRC) a Shannon capacity of 30-something kbit/s, which was closely approached with V.34, which used trellis coded modulation plus basically every other cod…

Not quite, and an interesting story that fits these engineering maxims better than you might think.

Huh? The SotA for dial-up modems in the 1990s was indeed 56 kbps, achieved with various encoding and compression hacks in both domains including trellis coding.

Weirdly enough, you can apparently still buy them from US Robotics: https://www.usr.com/products/56k-dial-up-modems/

Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#78

Post by summa_tech »

nine_k wrote: post #75
pklausler wrote: post #45

Earlier quoted context omitted.

I think that Feynman was talking about preparing a freshman-level lecture for Caltech-standard freshmen, but maybe you have somebody else in mind.

I think if you understand something really well (anything: the law of gravity, the Curry-Howard isomorphism, electrolytic dissociation, general relativity,...), you can find a bunch of comparisons, or metaphors, or other ways to explain it so that an interested five-years-old will get a rough idea. A very rough idea indeed, but one that could allow them to ask qualitatively reasonable questions, and that forms an int…

The "interested" part does a lot of lifting though. It's really hard to explain things to uninterested people.

If the person you are explaining your project to is not interested in the technical side, presumably under the rather confused but popular theory that technical aspects are not relevant to technology ventures, you'll not be making headway. It's much better to just make up some dollar numbers and run with that.

Re: Akin's Laws of Spacecraft Design (2011) [pdf]

#80

Post by gcanyon »

JumpCrisscross wrote: post #68
gcanyon wrote: post #12

> The biggest commercial success is not the best technical design: Nokia N95 versus the first generation iPhone That’s not a good example. Neither is Beta vs VHS. The most they illustrate is a different law I am coining right here: Canyon’s Law of Design Optimization: you will inevitably choose to optimize for different metrics than your customers would wish. Don’t try to convince them they are wrong.

> That’s not a good example It’s a great example. One can list a litany of technical specifications on which the N95 is superior. That, however, doesn’t make it a superior product.

"technical design" vs. "technical specs"

I think we're in violent agreement.

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