Thanks to the seminal work of Howard and Hanks et al, the world is intimately familiar with the story behind perhaps the most epic hack of all time, the saving of the crippled Apollo 13 mission. But Apollo 13 is far from the only story of heroic space hacks. From the repairs to fix the blinded Hubble Space Telescope to the dodgy cooling system and other fixes on the International Space Station, both manned and unmanned spaceflight can be looked at as a series of hacks and repairs.
Long before the ISS, though, America’s first manned space station, Skylab, very nearly never came to fruition. Damaged during launch and crippled both electrically and thermally, the entire program was almost scrapped before the first crew ever arrived. This is the story of how Skylab came to be, how a team came together to fix a series of problems, and how Skylab went on to success despite having the deck stacked against her from the start.
If you don’t live in northern Europe, Alaska, or the extreme southern part of South America, there’s a 400-ton, $150 Billion space station flying over your head several times a day. It’s the International Space Station, and it’s the most complex and expensive construction project of all time. Look up at the right time, and you can see a point of light rising in the sky, brighter than any star, darting across to the opposite horizon.
The ISS-Above is a great device to keep tabs on the six astronauts currently orbiting our globe, but if you want to see the space station rise over the horizon… well, lugging a Raspi and an HDMI monitor outside isn’t the best solution. The Pulsar is a tiny wearable board with a ring of LEDs programmed with 50 future passes of the space station. When the station is overhead, the LEDs light up, and a bright object appears over the western horizon.
[Liam] brought his Pulsar to the most recent Hackaday Pasadena meetup, and as his wearable LEDs lit up, the ISS appeared right on cue. The evening was only tainted by a crazy lady who decided to argue the existence of the International Space Station.
If the space station were left to its own devices, the living quarters would get incredibly hot. There are computers, hardware, and six crew members, all generating heat that must be gotten rid of. To do this, there are two heat exchangers inside the station that take warm water, dump that heat to ammonia, and send that ammonia out to panels outside the station. On December 11, 2013, Loop A of the thermal control system shut down, putting the station one failure away from evacuation. Plans for a spacewalk were tabled, but the ground crew managed to fix this hardware failure by telling the astronauts to push buttons, a metronome, and a software patch.
The problem with Loop A of the Internal Thermal Control System was a flow control valve that regulated the amount of ammonia flowing through the heat exchange. Too much ammonia, and the station would be far too cold. Too little, and it would be too hot. This valve is electronically controlled and takes exactly 13 seconds to move from open to closed. The first attempt at fixing the problem was having ground crew send the command to open the valve and cut the power halfway through. This involved using a metronome app on a phone to send two commands 6.5 seconds apart. It worked, but not quite well enough.
The failure of the metronome technique led [Todd Quasny] to write a script to turn the ‘on’ and ‘off’ commands from the ground to the ISS with millisecond resolution. This meant the commands to control the valve could be sent with the right delay, but they weren’t received with the right delay. This is a problem that had to be fixed from the station’s computers.
To finally solve the problem, ISS software engineer [Steve Joiner] was called in to write a software patch for the thermal control system. This is spaceflight and writing software is a long a laborious process of testing and code reviews. Nevertheless, the team managed to write and upload a patch in just two days.
This patch gave controllers the ability to control the valve with a resolution of 100 milliseconds, good enough for very fine control of the thermal system, and all without requiring the massive amount of planning that goes into a spacewalk or resupply mission.
A few months years ago, [Liam] funded a Kickstarter for a small desk toy that would tell him when the International Space Station was overhead. [Liam] got a little tired of waiting, so he decided to build his own with a Raspberry Pi and an astronomical computation Python library.
The impressive part of this build is computing where an orbiting object is in the sky given the ISS’ orbital elements. For this, [Liam] is using PiEphem, a library that can compute the positions of the sun, moon, planets, asteroids, and Earth-orbiting satellites given a location and a time. Since the ISS orbital elements change every so often, his software is set up to download an update every week or so.
[Liam] developed a few versions of his space station detector, each with a different display. The simplest uses a few LEDs, either through a LedBorg, Blinkstick, or PiGlow to serve as a notification of when the ISS is overhead. Two more complicated versions use an LCD display or LED matrix to signal when the next ISS pass will occur.
[Shingo Hisakawa] sent in a tip for a for a neat little box called the Levistone that tracks the Internation Space Station with a laser. His video log goes though all the steps for this great little project.
[Shingo] originally planned to pull orbital data down from NORAD and send that to an ArduinoBT board with ethernet, GPS and compass modules. In the original plan, the Arduino would do the orbit calculations and point the laser using a few servos. There wasn’t much success with making an Arduino do all the work, so the an Android phone stood in for the GPS, compass and connection to the web. The duty of calculating the location of the ISS using GPS and orbital elements was moved onto the Amazon EC2 cloud. The final product looks great, even if it’s impossible to record the beam for the video.
With the ability to calculate the azimuth and elevation of the ISS from any point in the world, [Shingo] came up with SightSpaceStation, a neat mashup of his data and Google Maps. There are also iOS and Android apps for a nice piece of work in augmented reality. It’s a great project that would really compliment the ISS desk lamp we covered a few days ago.
[Nathan Bergey] came up with a really neat desk lamp that provides a visualization of when the International Space Station is overhead.
The lamp uses a Teensy board to light a few LEDs on the edge of a piece of plexiglass. Because the orbit of the ISS decays over time, the time that overhead passes will occur is unpredictable after a few months. A stand-alone satellite tracking lamp will eventually lose it’s accuracy, so [Nathan] needed to parse tracking data the internet. Since he couldn’t find an API to track the ISS, [Nathan] wrote a Python script to parse the data he found on Heavens Above. Everything on the computer runs in the Gnome panel and is passed to the Teensy over the USB connection. [Nathan] posted all of the code is posted on github.
It’s a really great build that provides a reminder that there are people in space, and we think this would be a great way to provide some notification of upcoming Iridium flares, or when it’s most likely to pick up some APRS packets.
Check out [Nathan]’s demo of his ISS lamp after the break.
Years ago, he used to send APRS packets into space with a small rig powered by a 286 computer and HandiTalkie. These packets would drift off into space most of the time, but occasionally they would bounce back to Earth whenever the space station or PC Sat would fly by. The packets were often captured by other ham operators across the globe, who happened to be tuned to 145.825 MHz.
His interest renewed, he dug out his old HandieTalkie and Kantronics Terminal Node, aiming them towards the sky via an antenna situated in his back yard. When he returned 10 hours later, he found that he had collected all sorts of “space packets” from across the globe.
While not exactly a hack, it is definitely a neat exercise in ham radio operation. We can imagine slinging data packets off the space station would be an exciting experience for any budding operator (and OMs as well!)