SpaceX-developed rocket 'Falcon 9' is flying into space with Linux and C++


Official SpaceX Photos

SpaceX, a private space development company founded by NASA and Elon Musk, succeeded in launching a manned spacecraft using a reusable rocket `` Falcon 9 '' on May 31, 2020 Did. IT related news media ZDNet explains the software aspect of Falcon 9.

From Earth to orbit with Linux and SpaceX | ZDNet

Most advanced CPUs used in PCs and servers are not used in rockets and spacecraft. Since rocket development basically requires a long period of several years or decades, it is not unusual for a relatively new CPU to be used when it is developed, but to become an outdated model by the end of development. Because

In addition, since radiation flies around in space, the CPU used in space needs to strengthen its radiation resistance, so development will inevitably take time. For example, the CPU used in the command and control multiplexer/demultiplexer (C&C MDM) of the International Space Station (ISS), which is still in orbit, is a 20MHz model of the Intel 80386 developed in 1988.


NASA's Marshall Space Flight Center

Falcon 9 has three dual-core x86 microarchitecture CPUs, and the OS adopts Linux. The reason Falcon 9 has three CPUs is to guarantee the safety of redundancy. SpaceX uses the 'Actor-Judge' system that performs process processing on multiple cores at the same time and recalculates when the results differ, ensuring redundancy. In other words, the instruction is sent to the microcontroller only if all three installed CPUs have the same decision.

It is not clear what kind of chip is used in Falcon 9, but it takes more than 10 years to develop, so ZDNet points out that it is likely to be considerably older than at least the CPU in 2020. I am. However, since the Falcon 9 is a rocket with reuse in mind, the CPU used in the first stage of the rocket does not need radiation countermeasures, so it will be installed in the Raspberry Pi 3 in 2021. NASA is considering adopting the Arm Cortex-A53 ' for the Falcon 9 CPU.


Official SpaceX Photos

In addition, not only the hardware but also the software is independently developed. According to SpaceX developers, the software team for Falcon 9, Grasshopper and Crew Dragon is made up of 35 engineers. The mission is to develop each core platform, simulation software, ground station communication and analysis software, which is coded in C or C++.

Astronauts are also using the HP ZBook 15 , a mobile workstation with one of the Linux distributions Debian , Scientific Linux , and Windows 10. This terminal can be used as a remote terminal for C & C MDM, as well as for email and web browsing.

In addition, Crew Dragon, a manned spacecraft, uses a touch screen type interface, and the flight software UI coded in C++ is rendered with Chromium and Javascript. It also has physical buttons in case the touch screen breaks down.

by Official SpaceX Photos

in Software,   Hardware,   Ride, Posted by log1i_yk