21
$\begingroup$

I've previously asked Roughly how many self-viewing cameras are present in a Falcon 9 LEO mission? asking if it's closer to a dozen or a hundred on a log scale, because I have a hunch there's probably three dozen imaging devices present altogether, even if they're not all active at the same time.

Then I saw this answer - the last paragraph says:

To sum it up, selfie capabilities offer no scientific value but add costs. A selfie capability is however important for marketing and PR purposes, as it allows the operator to share footage with the public. I am thinking about the glorious footage from the Falcon 9, or the propaganda-heavy Chinese Space Station footage taken from its companion satellite Banxing-2.

I think this is probably wrong as it is written - considering the continuous and rapid rate of technology evolution going on with each new launch.

$\endgroup$
  • 8
    $\begingroup$ Technically not spacex related, but after the Columbia disaster it became standard procedure for Space Shuttle going to the ISS to do a 360 flip infront of the ISS so that the ISS cameras could take high res photos of the space shuttle so that ground teams can inspect for damage. $\endgroup$ – David says Reinstate Monica Jan 27 '17 at 19:29
  • 2
    $\begingroup$ @DavidGrinberg indeed. Considering that extremes of temperature and pressure are packed so tightly in some spacecraft and all are subjected to micro- (and perhaps not so micro-) meteorites, sometimes a camera is really helpful, especially during an active mission when you can't just Tweet a request for any other recordings that someone else may have made :) $\endgroup$ – uhoh Jan 27 '17 at 19:53
36
$\begingroup$

A caveat about this answer: it's not about SpaceX directly, more about the use of self-inspection cameras in general across space and launch vehicles.

It is used for engineering and status information. "Selfie" footage has been standard (at least on launch vehicles) since Apollo. Telemetry offers a very limited view of things and is prone to misinterpretation in the event of unanticipated failures. We only need to look at the last Progress failure to see how the telemetry failed to tell the whole story.

While self-inspection capability may offer no scientific value (to the extent that a satellite offers scientific value), it offers operational value by providing a means to confirm or rule out potential failure situations, which may inform operational decisions on how or whether to mitigate them. The decision whether or not to include this self-inspection capability is ultimately driven by a trade on whether the additional mass and complexity is balanced by the operational benefit it provides.

On the ISS, which is admittedly in a class of its own, it offers enormous benefit as an unparalleled means of continuously monitoring vehicle health. This is of particular importance for detecting things for which there is no real plausible telemetry alternative, or for which the available telemetry is not sensitive enough to paint a complete picture.

To say that these cameras only offer PR value is flatly false. The strongest evidence for this is the fact that the overwhelming majority of imagery produced by launch and space vehicle "selfie" cameras is never released to the public.

$\endgroup$
  • $\begingroup$ Thank you for the perspective! I wonder if it would be appropriate or helpful to also leave a similar or related answer to the original question that got this whole thing rolling. $\endgroup$ – uhoh Jan 27 '17 at 16:28
  • 8
    $\begingroup$ Appolo 13 dammage were known only by telemetry mesures and sound heard by the crew, and they wre greatly surprized when, on their way back to earth (when eath telescopes were close enough for images), they heard that part of their hull had blown up. A "selfie camera" could have been usefull here. $\endgroup$ – Nygael Jan 27 '17 at 16:58
  • 1
    $\begingroup$ Agreed. One of the links in the Columbia accident chain was that on that flight, no robotic arm was installed. If it had been, the arm mounted cameras could have looked for the wing leading edge damage. $\endgroup$ – Organic Marble Jan 27 '17 at 22:02
  • 5
    $\begingroup$ @Nygael: The Apollo SM wasn't imaged from Earth. When the SM separated from the CM, the astronauts had a brief opportunity to view and photograph the SM. $\endgroup$ – Hobbes Jan 28 '17 at 8:48
  • 1
    $\begingroup$ @uhoh Bingo. A picture is worth a thousand telemetry streams sometimes. $\endgroup$ – Tristan Jan 31 '17 at 14:28
15
$\begingroup$

There is value added. I was an operator of a satellite that had a video of the satellite being deployed. We were able to see from the video that the deployment was clean.

I assume if nothing goes wrong, the only value is PR, but if something does go wrong, video can help considerably.

EDIT: This kind of thing is exactly what might be useful from the ZUMA mission debacle. By having the footage available they can presumably remove several branches from a root cause of failure analysis, and provide another truth to verify the sensor. For instance, if the contact sensor reported it was disconnected, you could see if that was the case. You could spot mechanical failures, which telemetry might indicate there was a problem, you could spot exactly where it happened.

$\endgroup$
  • $\begingroup$ Great! Actually, this information would be much more helpful if you added it also to the linked question and/or answer. This question is a derivative of that. Thanks!! $\endgroup$ – uhoh Jan 27 '17 at 17:07
  • 2
    $\begingroup$ It would be helpful to give an example or two to show the kind of issue a camera would detect that is not available through telemetry... e.ge the solar panels were fully unfolded and latched, the antenna was not bent, things lke that.. $\endgroup$ – Innovine Jan 28 '17 at 7:50

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.