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1355 points LorenDB | 2 comments | | HN request time: 0.416s | source
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whatever1 ◴[] No.44300677[source]
Question why is it so easy today to build reusable rockets? Is it because the onboard cpu speed of the chips can solve more granular control problems with low latency?
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roshdodd ◴[] No.44301068[source]
As someone who actively works in the field, it was a culmination of:

- Advances in rocket engine design & tech to enable deep throttling

- Control algorithms for propulsive landing maturing (Google "Lars Blackmore", "GFOLD", "Mars Landing", and work through the references)

- Forward thinking and risk-taking by SpaceX to further develop tech demonstrated by earlier efforts (DC-X, Mars Landing, etc.)

Modern simulation and sensor capabilities helped, but were not the major enabling factors.

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hinkley ◴[] No.44302182[source]
I recall hearing SpaceX cite manufacturing improvements as well. How do you feel about materials science and the ability to source parts not made of unobtanium?
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1. Tuna-Fish ◴[] No.44302442[source]
Many of the hardest problems facing rocket engines are about temperature, heat and thermal density, not structural strength.

This means that 3d-printed copper (alloy) is an amazing process and material for them. You can build the kind of structurally integrated cooling channels that the people building rockets in the 60's could only dream about, and it's not a gold-plated part that required a million labor hours to build, it's something you can just print overnight.

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2. hinkley ◴[] No.44311525[source]
I learned a couple of years ago that the people in the sixties did in fact 3d print, but they did it via electroplating and wax. It took weeks to print a Saturn V rocket bell because they had to build up something like 5mm of material onto the outside of the bell after carving the channels into the outer surface of the inner bell and then packing them with wax.