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I remember watching a few videos awhile back talking about origami designs in spacecraft:

Origami in Space: BYU-designed solar arrays inspired by origami

Engineering with Origami

I've only done a cursory search (and it seems really hard to get images of recent satellites and their designs on Google...) but why am I not finding images of more folding satellites? Wouldn't a bigger solar panel = better? Even starlink seems to be a flat device that folds out boringly in a rectangular way.

Seeing how the Brigham Young University video is more than 7 years old, I'd thought we'd see something more elaborate unfold by now. Am I just not looking in the right places? Or are there still challenges that need to be overcome? Or is it just the fact that most spacecraft don't need a giant solar panel or antenna (since that seems to be the two applications most suited for a lot of folding)?

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    $\begingroup$ Possibly part of the problem is that the most interesting antenna are currently on military satellites, so while their folding probably counts, they are less likely to produce papers on how they fitted 100 meters of antenna in en.wikipedia.org/wiki/USA-223 $\endgroup$
    – GremlinWranger
    Sep 27, 2021 at 2:49
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    $\begingroup$ The ISS arrays pack into boxes in a very cool way. space.stackexchange.com/a/23953/6944 $\endgroup$
    – Organic Marble
    Sep 27, 2021 at 2:57
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    $\begingroup$ Part of the problem is that origami does not translate well into unfolding rigid panels. Origami assumes flat, semi-flexible panels that do not mind being bent and unbent. This is utterly different from reality, where making a folding hinge element is a mass- and complexity-intensive operation, beset with potential issues like vacuum welding, thermal stiction, etc. $\endgroup$
    – CuteKItty_pleaseStopBArking
    Sep 27, 2021 at 21:28
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    $\begingroup$ A different and interesting question you might ask separately is "How many origomi-like structures have been launched to space?" $\endgroup$
    – uhoh
    Sep 29, 2021 at 0:09
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    $\begingroup$ The art of origami is to transform a boring piece of paper into nice-looking or suggestive shapes. We do not need nice-looking geometric shapes for satellites. Even a capsule named Dragon does not need to look like one. What is usually needed is reliable deployment mechanisms, mostly for solar panels and antennas. I am not convinced that an origami-inspired mechanism is always best in terms of reliability and compactness. $\endgroup$
    – Ng Ph
    Sep 29, 2021 at 22:00

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The James Webb Space Telescope (finally scheduled to launch mid December 2021) with its folded-up sunshield and primary mirror counts as an origami spacecraft. Those structures need to unfold themselves after launch in an automated fashion.

The JWST has 344 single points of failure, several of which are criticality 1, which means the vehicle is essentially dead should the failure occur. Some of those criticality 1 single points of failure are to be expected but are only expected to occur after the vehicle has successfully operated for a decade. These expected end-of-life criticality 1 single points of failure include running out of liquid helium and running out of propellant.

One key problem with the JWST is that several of those criticality 1 single points of failure are related to the automated unfolding of the sunshield and primary mirror. There are about 50 related just to the unfolding of the sunshield, and many more related to the unfolding of the primary mirror. A criticality I failure after the vehicle has operated successfully for a decade is to be expected. A criticality I failure before the vehicle has started operating is another thing entirely, and it might well be the reason we do not see very many origami spacecraft.

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    $\begingroup$ I will be crossing my fingers whilst knocking on wood and throwing salt over my shoulder in a silly superstitious behavior attempt to help / hope that the JWST does unfold its sunshield and primary mirror correctly. I want that spacecraft to succeed. $\endgroup$
    – David Hammen
    Sep 30, 2021 at 12:05
  • $\begingroup$ Perfect answer. Luckily JWST went off perfectly but this is exactly the reason origami spacecraft are avoided as much as possible. The amount of testing that JWST required was utterly immense and was the dominant factor in why it so incredibly expensive. When you are spending such immense amounts of money on spacecraft and cannot repair them you want to keep the number of failure options as low as possible. $\endgroup$
    – Pioneer_11
    Mar 31, 2022 at 1:23
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It's a mixture of a number of factors, but the mechanisms required for "origami" spacecraft tend to make them heavier, more complex, more expensive and more prone to failure than a single piece spacecraft and therefore tend only to be used when necessary. Furthermore, with the exception of solar arrays, most rockets have a large enough faring that their payloads run into weight limits before size limits (with the falcon heavy having a notably small payload bay for it's size). Therefore, "origami" elements simply tend not to be necessary.

To address your solar panel question specifically. Unless the excess solar power is can be put to good use a larger solar panel generally just means more weight and therefore is not desirable.

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  • $\begingroup$ Do you have any references to support your assertions? Such as that "most payloads run into weight limits before size limits", for example. Some examples of "single piece spacecraft" (Presumably meaning that there are no mechanical extensions) would be nice too. $\endgroup$
    – Organic Marble
    Sep 30, 2021 at 0:55
  • $\begingroup$ Single piece was poor phrasing on my part - although I believe a number of cubesats are built in that way - what I was referring to is how most satellites are built with a central body and one or two solar arrays on the side $\endgroup$
    – Pioneer_11
    Sep 30, 2021 at 1:11
  • $\begingroup$ as for fairings this image should give you a good idea (twitter.com/torybruno/status/1175046216104779776/photo/1) - as you can see Falcon heavy is the most restrictive as it's payload fairing is on the smaller end despite it having double or triple the payload capacity of the competition. While I don't have a quote to hand, I recall a number of people criticizing falcon heavy for this. Most of the rockets on this chart have payload to volume ratio's of 100-200kg/m3 (for LEO) whereas falcon heavy has a ratio of 440kg/m3 $\endgroup$
    – Pioneer_11
    Sep 30, 2021 at 1:36

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