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I would like to know if anybody has any advice regarding a preflight check that I am doing for a satellite.

I would like to know if anybody has any experience regarding a standard excel sheet for all the analysis that I will have to do: static, dynamic, acoustic, etc. I'm working through SICSA.

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  • $\begingroup$ Can you give us more information about this Excel sheet and what you have to do to fill it out? You say it is standard. Whose standard? $\endgroup$ – called2voyage Jun 26 '18 at 18:28
  • $\begingroup$ Well I am wondering how the industry uses load limits for example static loads will be -4<x<8, is that the right way to do it. What about acoustic loads, what is the proper way to quantify and apply those loads to my design. Is there any template for that kind of testing ? $\endgroup$ – Alakelele Jun 28 '18 at 10:00
  • $\begingroup$ Since A McKelvy points out that there is no template, you may need to ask separate questions for each area of difficulty. $\endgroup$ – called2voyage Jun 28 '18 at 11:32
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I am assuming that you are referring to satellite qualification, and not a final pre-launch check, which would depend greatly on the satellite in question.

In regards to qualification, there are a number of standard tests that space hardware undergo to assure proper functionality on orbit. Unfortunately, as far as I know, there is no standard excel sheet describing these tests, as each mission will have different requirements and consequently different testing schedules.

The first concern is static structural stability, assuring that the satellite superstructure will hold up to the normal accelerations during launch and the more mundane 1G accelerations felt during the phases of its assembly and testing. This is usually performed in a centrifuge and iterated through multiple spacecraft orientations.

After this, the spacecraft is typically subjected to environmental testing. A thermal vacuum chamber is used to subject the satellite to a near vacuum and a cycle it through a range of temperatures that is equal to or greater than the expected operational range. Depending on the mission, this phase of testing may include radiation and magnetic field exposure.

Sometimes bunched with environmental testing is the launch dynamics testing. Large shaker tables are used to subject the spacecraft to vibrations that simulate the launch profile. This testing is also used to determine modal natural frequencies of the spacecraft. If required this phase also includes acoustic testing which simulates the acoustic profile inside the fairing.

Some satellites (certainly many satellite subsystems) require EM noise testing. For this testing, the satellite is placed in a listening chamber wherein the electronics are powered up to determine the EM noise generated and determine if it is within mission parameters.

During and after all of these, the on-board systems are usually tested to verify that the telemetry/comms are all nominal. Beyond these physical tests, satellites typically under go vast functionality testing to assure that the electronics all function properly, subsystem intercoms work effectively, ground station communication systems are functional, and software systems trip no errors.

All of the things I've listed are extremely general. The truth is that these tests, like most things in the space industry, are highly specialized. They are not required for every payload, just some; many payloads will require specific testing which I have not listed here. It takes a person with an intimate knowledge of the spacecraft's systems and the mission requirements to properly determine what pre-flight testing needs to occur. I recommend you ask a supervisor.

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  • $\begingroup$ Thank you for your answer, those tests are exactly what I have been reading about. The biggest unknown for me right now is how to test with software the shock events and also how to properly configure the acoustic test. If I understood correctly only very thin objects will suffer from that test, do we know a general threshold for thickness ? Thank you $\endgroup$ – Alakelele Jun 28 '18 at 10:06
  • $\begingroup$ @Alakelele - It depends on the launch configuration. The primary concern is the electronics and instrumentation. You should explore the structural characteristics of the weakest/most critical parts of your system and compare it to the amplitude/frequency of the acoustic profile you expect. I'm no expert on acoustic responses, but I would guess that the sound wave amp/freq are good upper bounds for the strain and oscillation being applied to thin components. Compare this to the yield strengths and fatigue tolerances of the material. $\endgroup$ – A McKelvy Jun 28 '18 at 12:46

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