"NASA Shuts Off Voyager Science Instrument, More Power Cuts Ahead to Keep Both Probes Going"
Incredible engineering that two probes, launched 50 years ago, are still going and that we're able to control them from this distance to shut off systems and prolong their lives. Truly a marvel.
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Self-promoting pawn
A neat bit of engineering in this video as the maker designed a 3d-printedd pawn which, upon reaching the final row of the board, transforms into a silhouette that is similar to the queen.
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Air powered RC Plane
I hold a deep love for the amateur engineers pursuing unique things. There is the guy who did vertical landing on his home rocketry, or RC 3d printing engineers. And I use amateur here to mean they are pursuing a project off the clock, sometimes these folks are actual engineers.
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FLIP Maritime research vessel set to retire after 60 years
The ship which rotates and sinks the majority of its length is retiring after 60 years.
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Akin's Laws of Spacecraft Design
- Engineering is done with numbers. Analysis without numbers is only an opinion.
- To design a spacecraft right takes an infinite amount of effort. This is why it's a good idea to design them to operate when some things are wrong .
- Design is an iterative process. The necessary number of iterations is one more than the number you have currently done. This is true at any point in time.
- Your best design efforts will inevitably wind up being useless in the final design. Learn to live with the disappointment.
- (Miller's Law) Three points determine a curve.
- (Mar's Law) Everything is linear if plotted log-log with a fat magic marker.
- At the start of any design effort, the person who most wants to be team leader is least likely to be capable of it.
- In nature, the optimum is almost always in the middle somewhere. Distrust assertions that the optimum is at an extreme point.
- Not having all the information you need is never a satisfactory excuse for not starting the analysis.
- When in doubt, estimate. In an emergency, guess. But be sure to go back and clean up the mess when the real numbers come along.
- Sometimes, the fastest way to get to the end is to throw everything out and start over.
- There is never a single right solution. There are always multiple wrong ones, though.
- Design is based on requirements. There's no justification for designing something one bit "better" than the requirements dictate.
- (Edison's Law) "Better" is the enemy of "good".
- (Shea's Law) The ability to improve a design occurs primarily at the interfaces. This is also the prime location for screwing it up.
- The previous people who did a similar analysis did not have a direct pipeline to the wisdom of the ages. There is therefore no reason to believe their analysis over yours. There is especially no reason to present their analysis as yours.
- The fact that an analysis appears in print has no relationship to the likelihood of its being correct.
- Past experience is excellent for providing a reality check. Too much reality can doom an otherwise worthwhile design, though.
- The odds are greatly against you being immensely smarter than everyone else in the field. If your analysis says your terminal velocity is twice the speed of light, you may have invented warp drive, but the chances are a lot better that you've screwed up.
- A bad design with a good presentation is doomed eventually. A good design with a bad presentation is doomed immediately.
- (Larrabee's Law) Half of everything you hear in a classroom is crap. Education is figuring out which half is which.
- When in doubt, document. (Documentation requirements will reach a maximum shortly after the termination of a program.)
- The schedule you develop will seem like a complete work of fiction up until the time your customer fires you for not meeting it.
- It's called a "Work Breakdown Structure" because the Work remaining will grow until you have a Breakdown, unless you enforce some Structure on it.
- (Bowden's Law) Following a testing failure, it's always possible to refine the analysis to show that you really had negative margins all along.
- (Montemerlo's Law) Don't do nuthin' dumb.
- (Varsi's Law) Schedules only move in one direction.
- (Ranger's Law) There ain't no such thing as a free launch.
- (von Tiesenhausen's Law of Program Management) To get an accurate estimate of final program requirements, multiply the initial time estimates by pi, and slide the decimal point on the cost estimates one place to the right.
- (von Tiesenhausen's Law of Engineering Design) If you want to have a maximum effect on the design of a new engineering system, learn to draw. Engineers always wind up designing the vehicle to look like the initial artist's concept.
- (Mo's Law of Evolutionary Development) You can't get to the moon by climbing successively taller trees.
- (Atkin's Law of Demonstrations) When the hardware is working perfectly, the really important visitors don't show up.
- (Patton's Law of Program Planning) A good plan violently executed now is better than a perfect plan next week.
- (Roosevelt's Law of Task Planning) Do what you can, where you are, with what you have.
- (de Saint-Exupery's Law of Design) A designer knows that they have achieved perfection not when there is nothing left to add, but when there is nothing left to take away.
- Any run-of-the-mill engineer can design something which is elegant. A good engineer designs systems to be efficient. A great engineer designs them to be effective.
- (Henshaw's Law) One key to success in a mission is establishing clear lines of blame.
- Capabilities drive requirements, regardless of what the systems engineering textbooks say.
- Any exploration program which "just happens" to include a new launch vehicle is, de facto, a launch vehicle program.
- (McBryan's Law) You can't make it better until you make it work.
- There's never enough time to do it right, but somehow, there's always enough time to do it over.
- If there's not a flight program, there's no money. If there is a flight program, there's no time.
- You really understand something the third time you see it (or the first time you teach it.)
- (Lachance's Law) "Plenty of time" becomes "not enough time" in a very short time.
- Space is a completely unforgiving environment. If you screw up the engineering, somebody dies (and there's no partial credit because most of the analysis was right...)
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We now understand Roman concrete
Fascinating stuff. I watched a TikTok about it last night. The core is that there are larger than expected chunks of limestone in the cement mix. Their unusual size means that many cracks involve them, and when water runs through these cracks the limestone basically is porous and dissolves to be a bit more glue to fill the crack, dry and harden. However, the other major realization is that it was mixed while being hot, rather than as we do today with cold mixing.
Here's the abstract of the paper:
Ancient Roman concretes have survived millennia, but mechanistic insights into their durability remain an enigma. Here, we use a multiscale correlative elemental and chemical mapping approach to investigating relict lime clasts, a ubiquitous and conspicuous mineral component associated with ancient Roman mortars. Together, these analyses provide new insights into mortar preparation methodologies and provide evidence that the Romans employed hot mixing, using quicklime in conjunction with, or instead of, slaked lime, to create an environment where high surface area aggregate-scale lime clasts are retained within the mortar matrix. Inspired by these findings, we propose that these macroscopic inclusions might serve as critical sources of reactive calcium for long-term pore and crack-filling or post-pozzolanic reactivity within the cementitious constructs. The subsequent development and testing of modern lime clast–containing cementitious mixtures demonstrate their self-healing potential, thus paving the way for the development of more durable, resilient, and sustainable concrete formulations.
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17-year old improves electric motor design such that it might see commercial uses in things like electric vehicles, and in doing so ease reliance on rare elements
As much as I enjoy the 17-year old inventor angle, this was also a great deep dive into electric motors and their production and environmental issues.
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How Howard Hughes used Beach Balls in the Spruce Goose (aka the H4 Hercules)
A fascinating tidbit of history of one of the most well known planes of American history.
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Slow Races On A Pinewood Derby Track Built From Scratch
Literally every time I hear about something relating to pinewood derbies, I am left with a very large yearning to do one.
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