SpaceX technologies

[Nytro]

Am gasit un post interesant:

 

SpaceX uses an Actor-Judge system to provide triple redundancy to its rockets and spacecraft. The Falcon 9 has 3 dual core x86 processors running an instance of linux on each core. The flight software is written in C/C++ and runs in the x86 environment. For each calculation/decision, the "flight string" compares the results from both cores. If there is a inconsistency, the string is bad and doesn't send any commands. If both cores return the same response, the string sends the command to the various microcontrollers on the rocket that control things like the engines and grid fins.

The microcontrollers, running on PowerPC processors, received three commands from the three flight strings. They act as a judge to choose the correct course of actions. If all three strings are in agreement the microcontroller executes the command, but if 1 of the 3 is bad, it will go with the strings that have previously been correct. The Falcon 9 can successfully complete its mission with a single flight string.

 

The triple redundancy gives the system radiation tolerance without the need for expensive rad hardened components. SpaceX tests all flight software on what can be called a table rocket. They lay out all the computers and flight controllers on the Falcon 9 on a table and connect them like they would be on the actual rocket. They then run a complete simulated flight on the components, monitoring performance and potential failures.

SpaceX engineers perform what they call "Cutting the strings" where they randomly shut off a flight computer mid simulation, to see how it responds.

Dragon uses a similar triple redundant system for its flight computers.

 

After talking with the Dragon team at GDC2016, it appears Tesla hardware is not used. They do use some interesting software on Dragon 2. They use Chromium and JavaScript for the Dragon 2 flight interface. The actual flight computers still run on C++.

Source: Discussion with various SpaceX engineers at GDC 2015/2016

 

Via: https://space.stackexchange.com/questions/9243/what-computer-and-software-is-used-by-the-falcon-9/9446#9446

[Guest]

Daca tot suntem la off-topic, am o intrebare pentru voi:

 

Acum totul e frumos intre SpaceX si NASA... Credeti ca NASA incearca sa "fure" de la SpaceX (tehnologie de construire si lansare a navetelor, etc) pentru a merge pe cont propriu in viitor, sa scape de astia? Sau credeti ca expeditiile astea in spatiu numai prin efort colaborativ se pot face? Din ce am citit SpaceX are rolul de a construi navetele si a de a le lansa pentru entitatile ce au nevoie de aceste servicii... Cum credeti ca vor evolua lucrurile?

Edited May 31, 2020 by Guest

[Nytro]

Eu cred ca vor colabora. La urma urmei, SpaceX nu prea are ce sa faca fara ajutor financiar de la NASA. Chiar daca vor oferi servicii de mers in spatiu pentru oameni simpli (e.g. pentru a filma un film porno in spatiu) sau daca vor primi bani pentru cercetare si vor trimite oameni pe Marte, ei nu au fondurile de care dispune NASA de la Guvernul american. 

 

Pe de alta parte, nu inteleg de ce NASA ar avea nevoie de ajutorul lor. La banii pe care ii au ii pot cumpara. Daca cineva stie mai multe despre colaborarea intre ei, si eu sunt interesat.

Intre timp s-a cam lamurit problema: nu folosesc Windows 10 cum pare sa se vada pe acele display-uri. Ei bine, nu e garantat asta, dar nu cred ca e necesar pentru ei. 

[yoyois]

@aismen Ca sa nu o dam in conspiratii prea mari, NASA nu prea construieste rachete.

Nasa comanda si foloseste rachete de la alte firme. deci ei nu prea pot folosi nimic din ce ar fura. Ca exemplu SLS (o noua racheta in dezvoltare) e facuta de Boeing care e contractat de NASA.

 

In plus 'Commercial Crew Program' in care SpaceX lanseaza astronauntii acum e vechi de zece ani.

 

Dupa parerea mea face sens ca NASA sa incurajeze companii private sa-si dezvolte tehnologia proprie si dupa NASA sa cumpere doar cate un zbor(in loc sa cumpere toata racheta+tehnologia).

 

Dupa parerea mea, se incearca o colaborare care sa reduca preturile pt toata lumea. Asta nu inseamna ca Boeing nu face lobby politic si nu face mizerii ca sa castige mai multi bani de la guvern...

 

 

Inspector General Accuses NASA of Favoritism to Boeing Over SpaceX

 

NASA paid SpaceX for safety review after Musk smoked pot (sponsored by boeing)

 

[ardu2222]

Stiti ca schema de baza ca si concept a motoarelor ionice pe baza de rhodium - krypton figureaza intr-o carte de fizica nucleara despre plasma scrisa in Romania in anii 80"? Profesorii si cercetatorii care au scris tratatul chiar au specificat ca in viitor se vor putea utiliza pentru "rachete cosmice". Daca gasesc cartea la anticariat o voi digitaliza

P.S scuze de offtopic.

Edited June 1, 2020 by ardu2222

[Nytro]

Interesant, daca ai ocazia ar fi util de stiut. Cred ca in anii "trecuti" Romania statea bine la capitolul cercetare.

In prezent nu prea se pot fura bani din acest domeniu asa ca politica s-a indreptat spre altele.