Pololu Compatible Relay Driver

[Bart] built a couple dozen Pololu compatible relay drivers.

If you have a Reprap, you’re probably familiar with the Pololu stepper motor driver. These tiny pieces of kit provide stepper motor control for Gen 6, RAMPS, or Sanguinololu Reprap electronics. There’s a small problem with all these boards, though; there’s no way to control any high-power devices from these boards except for stepper motors. Controlling a spindle for a home-built CNC router would be great, but apart from attaching a Dremel to your x-axis, you’re just about out of luck.

[Bart]’s relay driver takes the step and direction inputs from the stock Pololu stepper driver and connects each of those to a MOSFET. From there, a relay can be hooked up to the driver to control the spindle for a router, or a whole bunch of fans for a homebrew laser cutter.

The schematic and Gerber files are up on [Bart]’s webzone. The part count is very low, and the entire board could easily be built on a piece of perfboard. Check out the demo on the other side of the jump.

Continue reading “Pololu Compatible Relay Driver”

3D Printed Electromechanical Computer

A few nights ago, [Chris Fenton] was hanging out at NYC Resistor putting in some time on his electromechanical computer project. You might remember [Chris] from his tiny Cray that he’s putting an OS on. It seems [Chris] is going back in time about 150 years and has set his sights on a 3D printed version of [Babbage]’s Analytical Engine.

The Analytical Engine was is a remarkable feat of engineering and machining. It was the first programmable computer. Shame, then, that it was never built in the 1800s. [Chris] isn’t building a glorified calculator like [Babbage]’s polynomial-computing Difference Engine – he’s going all out and building something with conditional looping.

[Chris] calls his device an electromechanical computer, so we’re assuming it won’t be crank driven like the version in the British Science Museum. Right now, he’s constructed the decade-counting gears that are vitally important for the ALU of his design. All the parts were printed on a Thingomatic, so we’re betting [Chris] is going to be relying heavily on the MakerBot automated build platform for the thousands of parts he’ll have to fabricate.

Check out the video from NYC Resistor after the break.
Continue reading “3D Printed Electromechanical Computer”

Beating The Wrong Amateur Balloon Record

Friday, we covered a little project that attempted to beat the UK altitude record for an amateur balloon launch. Things don’t always go as planned, but the APEX team did manage to beat the several other UK records, including ones for the longest distance and flight duration for a latex balloon.

The APEX team was originally trying to beat the altitude record set by [Darkside] and his Horus 15.5 payload that made it to 40,575 meters. The APEX balloon was launched and slowly climbed over the North Sea to the expected burst point. Unfortunately for the trackers, the balloon leveled off at about 36km and just kept going.

The total Great Circle distance of the APEX Alpha flight was 1347km, with a total flight time of 12 hours, 20 minutes. The balloon eventually drifted out the radio range of anyone aware of the project. Despite the valiant efforts of HAMs across Europe, APEX Alpha was lost in the “HAM wastelands of Eastern Europe,” somewhere over Poland.

Even though the APEX team lost contact with their balloon, Alpha was still transmitting at the time. The balloon surely burst at this point, so it could have landed anywhere from Poland to Ukraine to Russia. The APEX team is offering a reward for finding Alpha, so if you see a small styrofoam box in Eastern Europe, drop the APEX boys a line.

Of course this flight couldn’t have taken place without the efforts of HAMs across Europe. [Darkside], [2E0UPU], and so many others helped out with the tracking as Alpha passed over the Netherlands and continued towards Berlin. The last contact was made by the awesome [OZ1SKY], who was very gracious to stay up until the wee hours of Sunday morning.

Not a bad flight for something that was supposed to take a swim in the North Sea. If you’d like to see the raw data from the flight, the APEX team posted everything they pulled down.

Medusa: A Proximity-aware Tabletop

Finally [Michelle Annett] can talk about her super secret project she did at Autodesk Research.

Medusa, as [Michelle]’s project is called, is a Microsoft Surface that has been fitted with 138 proximity sensors. This allows the Surface to sense users walking up to it, and detect users hands and arms above the table top. Multiple users can be detected at the same time, and the left and right hands of two users can be mapped to specific users.

The proximity sensors [Michelle] used are inexpensive, so we’re wondering when someone with a crazy multitouch setup will add proximity sensors to their build. We’d like to play with Medusa, even if just for a virtual game of Settlers of Catan. It seems like the perfect setup…

[Michelle] built Medusa last January during her internship at Autodesk. Now that UIST 2011 is over, she can finally talk about it. There’s also a video demonstrating the possibilities of Medusa, check it out after the break.

Thanks [Fraser] for sending this one in.

Continue reading “Medusa: A Proximity-aware Tabletop”

Going For The Amateur Balloon Altitude Record

At 11 AM London time, October 22, the Sutton grammar school for boys is going to be launching Apex Alpha, a high altitude amateur balloon for an attempt at the UK altitude record. Unlike a few other balloons we’ve seen, the Apex team is doing it right and giving everyone the downlink details for the balloon.

The payload for the balloon was built entirely by student of the Sutton grammar school and weighs less than 300 grams. While it’s not carrying a camera for the all-important pretty pictures, the payload does have a GPS module and a transmitter; it’s just enough to do the required testing on the lead up to Apex III.

Right now, the UK amateur balloon record stands shy of 130,000 feet. The team gained a lot of experience with their Apex I and Apex II launches, and they’re pretty confident they have the experience to pull this one off. You can check out the progress of the Apex Alpha flight on the spacenear.us tracker. For us Yanks, the launch should start October 22nd at 6:00 am Eastern time and 3:00 in the morning for the West coast. The team says they’ll be updating that throughout the flight.

UPDATE: Apex Alpha just won’t burst. Any HAMs near Berlin in Eastern Europe are sorely needed. Head over to the IRC chat if you can help.

Send A Satellite Into Space For $300

There’s a new Kickstarter campaign that promises to launch a personalized satellite into orbit for 300 bones.

The KickSat project is headed by [Zac Manchester], [Mason Peck], [Justin Atchison] and a few more contributors hailing from Cornell University. Their goal is to launch a CubeSat filled with hundreds of postage stamp-sized satellites and release these ‘Sprites’ into low Earth orbit.

The Sprite concept has been in development for a while now and has been featured on IEEE Spectrum. The tiny satellites are simple PCBs with a microcontroller and a radio powered by solar cells and capacitors. The first version of the Sprite is designed to beam down a few bytes of data – just a unique identifier and a Kickstarter backer’s name. Future versions will undoubtedly include more advanced sensors such as cameras, thermometers, and very tiny particle detectors.

The KickSat team will use the funding from the Kickstarter campaign to test and integrate the systems. The team hopes to hitch a ride on one of NASAs many CubeSat launches, but if they get funding from 400 people, they’ll get to fly on a commercial launch by early 2013.

We were wondering about the amazing amount of space junk this KickSat/Sprite build will produce, but the team says not to worry: The Sprites fly in a pretty low orbit and will reenter the atmosphere a few weeks after being deployed. Not bad, considering Sputnik orbited for only 3 months.