Questions tagged [flight-computer]
Questions regarding the computers onboard spacecraft which handle mission-critical data.
1
vote
1answer
116 views
How accurate can a satellite's orbit be?
How precise can an artificial satellite be when it comes to following the exact orbit in relation to Earth or hitting the same point above Earth in orbit? Which orbit would be the most stable for this?...
7
votes
1answer
222 views
How would the International Space Station be maintained unmanned?
Russia's lunch to the ISS failed and the crew may have to leave it unmanned. How would the ISS run without a crew? Could some one else take it over or squat in it?
https://www.npr.org/2018/10/11/...
3
votes
1answer
93 views
How does the Apollo LM ascent guidance program P12 actually work?
P12 is the AGC guidance program for normal ascent from the lunar surface to orbit. According to the mission planning documents, after separation and ignition, the ascent stage holds its initial ...
2
votes
2answers
136 views
Arcustangent function of the Apollo Computer, atan() or atan2()?
What type of the arcustangent function was used, the one with single argument only or the famous atan2(y, x) or arctan2(y, x) with two arguments x and y? What kind of aproximation was used?
119
votes
2answers
17k views
How did the Apollo computers evaluate transcendental functions like sine, arctangent, log?
Navigation with a sextant or maneuvers using gimbal angles might be two examples of cases where an Apollo computer might need to do trigonometry.
Trigonometric functions like sine, arctangent, etc. ...
9
votes
1answer
163 views
Problems as a result of clock drift that have occurred in space?
I was reading this question about the clock drift on the Apollo missions and am sure that a drift of 1 second / day on some of the longer missions would likely result in a mission failure due to the ...
3
votes
1answer
127 views
Apollo-11 AGC core memory has 5 wires per core (rather than 3 or 4) - why?
Apollo-11 AGC core memory has 5 wires per core (rather than 3 or 4) - why?
I am referring to this image in Wikipedia:
https://en.wikipedia.org/wiki/Apollo_Guidance_Computer#/media/File:...
10
votes
3answers
464 views
How many memory banks does Opportunity have?
Sparked by the comments to this answer, how many memory banks does Opportunity have? I'm specially interested in the flash memory but any other info is also welcome.
According to this JPL press ...
4
votes
1answer
148 views
Raspberry Pis in Space?
I'm aware of the Astro Pi (1, 2, 3, 4) on board the ISS, but have there been any other instances of the RPi in space (Astro or not), for example in cubesats or other spacecraft which contain a ...
9
votes
1answer
370 views
Timing accuracy of the Apollo Guidance Computer?
The AGC timing reference came from a 2.048 MHz crystal clock. But how accurate was this clock circuit? Note 3 of this schematic: "The value of the follwing components to be determined at unit test" is ...
7
votes
1answer
187 views
Cypress PSOC chips in a Cubesat
The Cypress PSoC line of microcontrollers, especially the PSOC 4 family are very versatile and capable, and seem a natural for use in cubesats.
Unfortunately, at least one experiment: http://www.dtic....
9
votes
1answer
198 views
What's the record for the longest time a deep space craft has functioned without a reboot?
The question How is Voyager 1 still operating? and the interesting comparison to the record times that Earthbound servers have run without reboot got me thinking about deep space spacecraft.
I'm ...
14
votes
2answers
608 views
How is Voyager 1 still operating?
I watched a documentary on Voyager 1 and 2 last night and wondered "how is the digital equipment on them still operating"?
I work in IT, and decided to look up what the longest running servers were - ...
23
votes
2answers
4k views
How complex was the math and physics necessary to place Apollo 11 on the moon?
Specifically, I'm interested in how closely the models used to calculate the various burns and course corrections represented reality. Was standard Newtonian mechanics sufficient or were relativistic ...
5
votes
1answer
925 views
How were these NASA engineers able to take men to the moon and bring them back with this limited computing capability?
The Apollo Guidance Computer had only 2k RAM and 32kb storage.
Also what O.S. did they use, and who made it?
0
votes
0answers
180 views
What are all the ways that FPGAs are used in the Flying Laptop spacecraft?
In the eoPortal's spacecraft Mission profile for the Flying Laptop, the term FPGA (Field Programmable Gate Array) appears 12 times, including the paragraph below. I'm still having trouble ...
18
votes
2answers
2k views
What was the first programming language in space?
Sputnik 1 was the first satellite in space. Did it have a programming language on board or was it purely analog?
in 1949 Von Neumann released the language Short Code.
Fortran was invented in 1957.
...
4
votes
2answers
256 views
Commercial grade single board computers (SBCs)
Suppose a nanosatellite is made with several commercial grade SBCs working together. And we design it so as to give output based on majority voting type of algorithm. I am aware of single event upsets ...
1
vote
0answers
88 views
What are the features of microcontrollers used in space? [closed]
What are the most desired features of microcontrollers used in space in on-board computers? Are there some special implementations, special functionality? Are features of some microcontrollers not ...
6
votes
1answer
177 views
Who built Juno's chipsets?
Lockheed Martin was responsible for the construction of Juno. But I was wondering who built the chips Juno uses for its onboard computers, and whether or not they are radiation hardened. I would ...
0
votes
1answer
379 views
Software development for Apollo [closed]
How was software developed during apollo?
From various sources, it can be gleaned that the computer was a ibm system 360, and the language was basically a fortran dialect or fortran.
What I'd like ...
23
votes
4answers
5k views
Is the Pi really fit for outer space?
Recently, there has been growing interest in using Raspberry Pis in CubeSats. NASA is even in on the trend. But, considering that outer space is pretty harsh on electronics (i.e. radiation and cosmic ...
15
votes
1answer
851 views
What space applications, projects and agencies are using the Ada programming language?
The answer to this question mentions the use of Ada-programmed applications on the ISS.
Ada was developed for the US DoD to replace a plethora of computer languages (some 465), for mission-critical ...
23
votes
9answers
6k views
Can you really use Arduino for a small spacecraft?
A group of Russian geeks intends to shoot a small vehicle to the moon, which is supposed to photograph the places of the Apollo landings. This will be the ultimate proof that people actually visited ...
13
votes
2answers
6k views
Which operating systems is the International Space Station running?
I've seen some of the articles mention that ISS switched from Windows to Linux. But that's just considering the laptops. What OS are the other computers present on ISS running? I would think that e.g. ...
12
votes
4answers
969 views
Successful Linux-based Cubesat missions?
Has anyone had any experience with successful Linux-based flight computer on Cubesat missions?
What Linux hardware was used and what problems did you encounter?
I am contracted to write flight/ground ...
11
votes
3answers
614 views
RTOS vs Linux against single event upsets
I am working on the on-board computer for a CubeSat. Our computer will be vulnerable to radiation, hence single event upsets, e.g. bit flips are likely to occur. Would a lighter, smaller OS like ...
8
votes
1answer
714 views
What is the maximum acceptable latency in rocket control computers?
Rockets require real-time computers, in that there are operational deadlines between events and system response. How quickly does the rocket's controller need to respond to sensors and events, without ...
17
votes
1answer
2k views
If the space shuttle computers all output contradictory commands, how is it chosen?
The space shuttle computers use triple-redundancy, and if one computer contradicted the other two, it would be ignored. I read that if all three gave contradictory output, one computer would be ...
16
votes
1answer
5k views
Operating system of New Horizons spacecraft
I've been doing some searching and I can find some technical details about the flight computer of the New Horizons spacecraft. What I've found is:
It has a Mongoose-V 32-bit CPU (a radiation hardened ...
3
votes
1answer
387 views
Why aren't there more guidance computers on cargo rated launch vehicles?
According to this video human-rated launch vehicles can have six guidance computers while cargo-rated launch vehicles seldom have more than two. If these computers function independently for greater ...
25
votes
2answers
28k views
What computer and software is used by the Falcon 9?
I don't know if this would be public, but what CPU / Microcontrollers are used and what software do they run on the Falcon 9? Do they use an OS or is it just bare metal programming?
I found some ...
9
votes
1answer
1k views
Using non-radiation-hardened processors in lunar orbit …
Is it feasible to design a flight computer for a small CubeSat spacecraft destined for lunar orbit that is controlled exclusively by one or more non-radiation-hardened processors? What are the main ...
4
votes
2answers
1k views
What are the MDM's on the ISS, and how many different kinds are there?
In the prelude for SpaceX CRS-3 mission, the failure of a Multiplexer-Demultiplexer (MDM) on the International Space Station (ISS) seems to be a real concern for launching.
In the pre-launch press ...
19
votes
1answer
4k views
Why is a stick required to operate Soyuz's computer?
In this screenshot from the recent Soyuz TMA-12M launch, a crewmember is seen using a stick to enter commands into the computer:
Is this stick standard, taken on all Soyuz flights? Also, why aren't ...
19
votes
1answer
2k views
Was the Apollo 13 CM guidance computer fully shut down?
I was watching the movie Apollo 13, and one thing struck me as quite odd. According to Wikipedia,
[Movie director Ron] Howard went to great lengths to create a technically accurate movie, employing ...
11
votes
1answer
551 views
Are all crew on board a spacecraft trained to handle flight-systems?
Spaceflightnow.com writes to say
(Edited to apply my highlights)
"The improvements are rather significant," Kelly said in a NASA interview. "The displays that the cosmonauts and myself ... use to ...
13
votes
4answers
2k views
Do any systems in space use Artificial Intelligence yet?
Technology has apparently advanced to the point some states in the Untied States are debating AI managed cars. The thought comes to mind that space is relatively less crowded than most streets on ...
21
votes
3answers
1k views
How often are ISS computers (MDMs) replaced?
The electronic "heart" of the International Space Station are the Multiplexers-Demultiplexers (MDMs) located within & outside the pressurized modules.
How often are they replaced? (An ideal ...
12
votes
1answer
3k views
Why did the ESA choose SPARC for LEON?
In late 1997, the European Space Agency started the LEON project to provide higher performance processors for ESA missions. An open instruction set architecture was a first-level requirement (both to ...
22
votes
1answer
1k views
How are flight plans calculated?
When a project like Rosetta is being developed, how are flight plans calculated? Do planners simply input the desired target into a program or a flight computer which spits out the optimum flight path ...
22
votes
1answer
5k views
On-board computer / data handling system of Rosetta - details?
I seek detailed information on the computer and/or data handling system of Rosetta.
Who manufactured it?
What type(s) of CPU is used?
What kind of architecture does it belong to and at what ...
