Hackaday Links: June 15, 2014

hackaday-links-chain

Love the classic brick Game Boy, but hate the low-contrast LCD, terrible battery life, and the inability to play Pokemon Emerald? This one’s just for you. It’s the ultimate DMG Game Boy – a Game Boy Advance SP stuffed (is it stuffed if it’s taking up more room?) into the classic Game Boy enclosure. Forum thread.

Zooming in to a microchip. It starts off with a DSLR and ends up on a scanning electron microscope. This is an older chip, and the CPU you’re using right now probably has much smaller features.

Every movie and every TV show set in space invariably has space helmets with LEDs pointing towards the face. Think how annoying that would be for an astronaut. Here’s how you add LEDs to a space helmet for a nice theatrical effect. Just don’t use it on a real EVA.

Everyone’s favorite crowdfunded space probe can apparently be detected with an 8-foot dish. That’s the same size as an old C-band dish, a.k.a West Virginia wildflowers. We know some of you have one of these out there, so go make a ~2GHz feed horn, grab a USB TV dongle, write it up, and send it in.

Alright, MAME cabinets. Say you want to go old-school and have a CRT. Some arcade games use a vertically oriented display, while other, slightly more modern games use a horizontally mounted display. How do you fix this? Get a big bearing, of course. This one allows a 19″ CRT to be rotated 90 degrees – all you need, really, if you’re switching between Pacman and Mortal Kombat.

Hey mechanical keyboard enthusiasts! Here’s some Hackaday Cherry MX keycaps. Informal interest check in the comments below. Suggestions welcome.

ISEE-3: On Track To Come Home

map

Intended trajectory from ICE team in 1986 (blue), 2001 ephemeris of ISEE-3 (white) and current ephemeris (red/green). Click to embiggen.

When last we heard of the progress of commanding the derelict ISEE-3 satellite into stable orbit between the Earth and the sun, the team had just made contact with the probe using the giant dish in Arecibo, sent a few commands, and started gathering data to plot where the spacecraft is and where it will be. A lot has happened in a week, and the team is now happy to report the spacecraft is alive and well, and much, much closer to the intended trajectory than initially believed.

Before last week, the best data on where ISEE-3 was heading was from a 13-year-old data set, leaving the project coordinators to believe a maneuver of about 50-60  m/s was necessary to put the spacecraft into the correct orbit between the Earth and the sun. With new data from Arecibo, that figure has been reduced to about 5.8 m/s, putting it extremely close to where the original ICE navigation team intended it to go, all the way back in 1986. This also gives the team a bit of breathing room; the original planned maneuver to capture the spacecraft required nearly a third of the available fuel on board. The new plan only requires the spacecraft expend about 5% of its fuel stores. This, of course, brings up the idea of continuing the planned mission of the rebooted ISEE-3 beyond the Earth-Sun L1 point, but that is very much putting the cart before the horse.

Of course, getting ranging data of the spacecraft is only a small part of what has happened with the ISEE-3 part this week. Thanks to the ‘away team’ sent to Arecibo to install hardware and attempt to make contact with the satellite, both transceivers are working, telemetry is being downloaded from the probe, and work has begun on refining the exact position of ISEE-3 to compute where and when the spacecraft needs to make its maneuver.

Regular Hackaday feature and software defined radio god [Balint] was on hand with the away team at Arecibo to install his company’s SDR unit on the largest dish on the planet. His happy dance of the first data from ISEE-3 made the blog rounds, but the presentation (PDF) and photo gallery tell the story of working on the largest dish on the planet much better.

There’s still a lot of work to be done by the ISEE-3 team as they figure out how best to capture the spacecraft and prepare for the burn in the following week. They should have the exact orbit of ISEE-3 nailed down early this week, and after that, ISEE-3 could on a path back home in less than two weeks.

Talking To ISEE-3

hello.again.m

ISEE-3, the plucky interplanetary spacecraft fueled by the dreams of thousands of crowdfunding backers and hydrazine is now transmitting data to Earth.

Where all radio contact with ISEE-3 this year has only been a carrier frequency, the folks at the reboot project have successfully commanded ISSE via the huge Arecibo telescope to transmit data back to Earth. Usable data are now being received at 512 bits/second at ground stations in Germany, Kentucky, and California, surely being looked over by the ISEE reboot project engineers.

Simply transmitting the commands to put the data multiplexers into their engineering telemetry mode was no small task; a power amplifier needed to be built, shipped to Arecibo, and installed in the giant dome hanging over the Arecibo dish. The amplifier was only installed in the last day, during an earthquake, no less.

There’s still a lot of work to be done before the project can go any further; the team will need to check the status of the spacecraft from the data received, more systems will be checked out, and eventually the spacecraft will be commanded to perform a 17-hour long burn with its small thrusters, putting it on course to be captured by Earth some time in August.

It’s an amazing achievement to do any sort of communication on this scale, and now events in the ISEE-3 mission timeline will be coming rather quickly. We’re trying to organize a video/blog/cast thing with the team from NASA Ames or Morehead State, but the team is, understandably, a little busy right now.

ISEE-3: Ready To Come Home

ISEE

The team working to reboot the ISEE-3 satellite hurtling towards an August encounter with Earth is hard at work. They’ve put up a crowdfunding page, and now that they’re completely funded (don’t stop donating, btw), they’re starting to go deeper into the waters that will allow them to capture a forgotten satellite.

The project put up a status report going over what they’ve accomplished so far, and what work has yet to be done. For a few months now, they knew both transmitters aboard the craft were operational, but they were not sending telemetry. The team has gone through the documentation, came up with a set of commands, and are currently en route to Arecibo to transmit those commands.

Two ground station transmitters are being constructed, one specifically built to be installed at Arecibo for this application. The other is a portable, self-contained 700 watt transmitter that will be used at the official ISEE-3 ground station in Morehead State University in Kentucky.

With transmitters taken care of and receiving handled by an SDR from Ettus Research, a lot of work has focused on the command and telemetry systems.  In 1978, the user interface for commands and telemetry was primitive to say the least. The team is now working on a system built-in Labview that’s much easier on the eyes than the vintage text terminal screens.

So far, signals from ISEE-3 are planned to be received at Arecibo, Morehead State, and Bochum observatory in Germany. This will give the team extremely good coverage for most of a day, and there are other ground stations in California that will extend the time the team is able to communicate with ISSE-3 each day by a few hours.

There’s still a lot of work to be done; the team really doesn’t know what systems are still operating, although most of them did make it 20 years with only one fault. In the next few days, we’ll all get to see if this satellite will be up to the task of coming back home to Earth. If everything goes to plan, ISEE-3 will be on track towards a 17 hour burn to put it on the correct trajectory some time in mid June.

ISEE-3 Dream Team Needs Your Help

ISEE-3 Moon flyby

The mission to save ISEE-3 has is underway. The ISEE-3 Reboot Project has posted a crowdfunding campaign on Rockethub. When we first covered the ISEE-3 story no one had heard from it since 2008. Since then AMSAT-DL, an amateur radio group in Germany has received signals from the probe.

The ISEE-3 Reboot Project is being managed by [Dennis Wingo] and [Keith Cowing], the same two men who spearheaded the effort to recover NASA’s Lunar Orbiter images from old magnetic tapes. They did most of their work using restored 1960’s equipment in a vacant McDonald’s.

The goal of the ISEE Reboot Project is to return ISEE-3 to its original Earth/Sun Lagrange point L1 orbit. Once safely back in orbit, it will be used for STEM education, amateur radio solar predictions, and for science about the sun. In [Dennis Wingo's] own words

If we can do this, we will have an open source, publicly accessible satellite data stream of the first open source satellite above Low Earth Orbit.

[Wingo] and [Cowing] aren’t alone in this effort; they are working with a venerable dream team. In addition to getting the nod from NASA, the team also has the help of [Dr. Robert Farquhar], the orbital dynamics guru who originally designed ISEE-3’s comet intercept orbit . [Farquhar] has an extremely personal reason to participate in this project. In 1982 he “borrowed” the satellite to go comet hunting. Once that mission was complete, he promised to give ISEE-3 back. [Dr. Farquhar] and his team designed the maneuvers required to bring ISEE-3 back to L1 orbit back in the 1980’s. This includes a breathtaking moon flyby at an altitude of less than 50 km. Seriously, we want to see this guy’s KSP missions.

Communicating with the ISEE-3 is going to take some serious power and antenna gain. The project has this in the form of a 21 meter dish at Moorehead State University in Kentucky, USA, and the Arecibo Observatory. Arecibo should be well-known to our readers by now. Moorehead and Arecibo have both received signals from ISEE-3. The reboot project team is also working directly with the AMSAT-DL team in Germany.

If this effort seems a bit rushed, that’s because time is very short. To implement [Dr. Farquhar's] plan, ISEE-3 must fire its thrusters by late June 2014. In just two months the team needs to create software to implement ISEE-3’s communications protocols, obtain and install transmitters at Moorehead and Aricibo, and send some basic commands to the craft. Only then can they begin to ascertain ISEE-3’s overall health in preparation for a thruster burn.

If  the ISEE-3 Reboot Project succeeds, we’ll have an accessible satellite well outside of low Earth orbit. If it fails, Issac Newton will remain at the helm. ISEE-3 will fly right past Earth, not to be seen again until August 2029.

[Read more...]

Follow

Get every new post delivered to your Inbox.

Join 92,317 other followers