Comment by WalterBright
5 hours ago
When I worked at Boeing, I talked about autoland systems with my lead engineer. He said the autoland was too perfect, as the airplanes would touch down at the same place every time.
This caused that place in the runway to suffer severe fatigue damage.
IIRC, there was a similar problem on aircraft carrier flight decks, where they had to induce some randomized amount of dispersion to keep the tailhook from hitting the same spot over and over again.
I work at a self-driving car company and we observed a similar problem when we did some off-road testing on dirt tracks. The cars were too precise and they were cutting deep ruts into the soil. We too solved it by adding a pseudo-random offset to the track.
Before the current wave of automation there was a previous technology to automate buses using optical sensing and lines in the road which had the same issue.
Hmm in distributed computer systems similar patterns exist, e.g. adding jitter to avoid thundering herd effects.
This feels like an essential pattern of the universe or something…
"Spread spectrum" is used in EE to spread out the frequency ranges used and reduce interference. The extreme version being CDMA.
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Citation please. Doesn't pass the sniff test.
I suspect the ocean in its various states provides quite a bit of dispersion. Replacing deck plates on a ship is a normal part of maintenance. I find it very hard to believe they'd induce randomness rather than having just that one plate get a different hardness (I know some people will screech about that but trust me, the warship industry is well practiced at such things).
Not sure about the ocean industry but carrier landings have full autoland support for a long time (see e.g. magic carpet).