Repairs You Can Print: Fixing A Chewed Up Remote

February 1, 2018 by 17 Comments

What is it about remote controls? They’re like some vortex of household chaos, burrowing into couch cushions while accusations fly about who used it last. Or they land in just the right spot on the floor to be stepped on during a trip to the bathroom. And don’t get us started about the fragility of their battery case covers; it’s a rare remote in a house with kids whose batteries aren’t held in by strips of packing tape.

But [Alex Rich]’s Bose radio remote discovered another failure mode: imitating a dog chew toy. Rather than fork out $90 for a replacement, [Alex] undertook a 3D-printed case to repair the chewed remote. He put an impressive amount of reverse engineering into the replacement case, probably expending much more than $90 worth of effort. But it’s the principle of the thing, plus he wanted to support some special modifications to the stock remote. One was a hardware power switch to disconnect the batteries entirely, hidden in the bottom shell of the case. The second was the addition of a link to his thermostat to adjust the volume automatically when the AC comes on. That required a Trinket inside the remote and a few mods to make room for it.

Yes, this project dates from a few years back, but [Alex] only just brought it to our attention for the Repairs You Can Print contest. Got some special unobtanium part that you were able to print to get out of a jam? Enter and win prizes to add to the glory of fixing something yourself.

Travel In Style On An Electric Air Sled

February 1, 2018 by 41 Comments

What do you do during the winter months in Ohio? Sledding of course! Sledding normally takes place on hills, but [Peter Sripol] is no slave to the terrain. He’s built an air sled to conquer the barren wastelands of unplowed parking lots. Air sleds aren’t as outlandish as you might think — the Soviet Union had decades of success with them.

The project starts with toboggan style plastic sled. [Peter] built a frame into the plastic using an aluminum square. The frame is used to support a motor pod at the back of the sled. The motor, of course, comes from his DIY electric plane project. Don’t worry — [Peter] didn’t cannibalize his plane. The plane’s motors are being upgraded, and this is one of the originals.

The motor itself is quite a beast. It’s a 150cc equivalent brushless outrunner motor from HobbyKing. It’s not cheap either at around $450 USD.  The motor is controlled by an equally beefy brushless controller wired into a standard R/C car receiver. A pistol grip transmitter makes a great wireless throttle for the system.

Steering is a much more mechanical affair. The sled’s rudder is controlled much like that of an airplane. A steel cable pull-pull system is connected to a stick mounted in front of the pilot. The unreinforced styrofoam rudder turned out to be a weak point in the build — check out the video after the break to see the full story.

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Mechanisms: The Screw Thread

February 1, 2018 by 65 Comments

They hold together everything from the most delicate watch to the largest bridge. The world is literally kept from coming apart by screws and bolts, and yet we don’t often give a thought to these mechanisms. Part of that is probably because we’ve gotten so good at making them that they’re seen as cheap commodities, but the physics and engineering behind the screw thread is interesting stuff.

We all likely remember an early science lesson wherein the basic building blocks of all mechanisms laid out. The simple machines are mechanisms that use an applied force to do work, such as the inclined plane, the lever, and the pulley. For instance, an inclined plane, in the form of a splitting wedge, directs the force of blows against its flat face into a chunk of wood, forcing the wood apart.

Screw threads are another simple machine, and can be thought of as a long, gently sloped inclined plane wrapped around a cylinder. Cut a long right triangle out of paper, wrap it around a pencil starting at the big end, and the hypotenuse forms a helical ramp that looks just like a thread. Of course, for a screw thread to do any work, it has to project out more than the thickness of a piece of paper, and the shape of the projection determines the mechanical properties of the screw.

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Twitter Celebration Of Scientist Hacks For Lab And Field

February 1, 2018 by 4 Comments

If you like reading about scientists creatively using household objects for their work, you will enjoy browsing Twitter hashtag #reviewforscience where scientists are sharing stories of repurposing everyday things for their lab and field.

Research papers focus on the scientific hypothesis and the results of testing it. It is very common for such papers to leave out details of tools and techniques as irrelevant. (A solid scientific conclusion should be reproducible no matter what tools and techniques are used.) This sadly meant much of scientists’ ingenuity never see light.

We can thank Amazon user [John Birch] for this event. His son wished to study how ants from different colonies interact. In order to observe how these groups of ants react to each other while still keeping the populations separate, he wanted to keep one group of ants inside a tea strainer. He posted this technique as a review on the tea strainer’s Amazon product page, where it caught the attention of @RobynJWomack and started spreading, taking off when @DaniRabaiotti suggested the tag #reviewforscience.

Sadly, it appears our original scientist (who posted under his dad’s Amazon account) did not succeed with the tea strainer technique. But he has succeeded in drawing attention to creativity in science worldwide, as well as making his dad internet famous.

We love lab hacks here. For scientists who wish there was a place to document their creative lab hacks, might we suggest Hackaday.io?

[via Washington Post]

The Hard-Learned Lessons Of The Columbia Disaster

February 1, 2018 by 136 Comments

On February 1st, 2003 at eighteen seconds past 9:00 AM Eastern Standard Time, the Space Shuttle Columbia broke up during atmospheric entry over Texas. Still traveling at approximately Mach 18.3, the disintegration of Columbia was complete and nearly instantaneous. According to the official accident investigation, the crew had at most one minute from realizing they were in a desperate situation to complete destruction of the spacecraft. Due to the design of the Space Shuttle, no contingency plan or emergency procedure could have saved the crew at this point in the mission: all seven crew members were lost in this tragedy.

While the Space Shuttle, officially known as the Space Transportation System (STS) would fly again after the Columbia disaster, even the program’s most ardent supporters had to admit fundamental design of the Shuttle was flawed. Steps needed to be taken to ensure no future astronauts would be lost, and ultimately, the decision was made to retire the Shuttle fleet after primary construction of the International Space Station (ISS) was complete. There was simply too much invested in the ISS at this point to cancel the only spacecraft capable of helping to assemble it, so the STS had to continue despite the crushing loss of human life it had already incurred.

Between the loss of Challenger and Columbia, the STS program claimed fourteen lives in its thirty year run. Having only flown 135 missions in that time, the STS is far and away the most deadly spacecraft to ever fly. A grim record that, with any luck, is never to be broken.

The real tragedy was, like Challenger, the loss of Columbia could have been prevented. Ground Control knew that the Shuttle had sustained damage during launch, but no procedures were in place to investigate or repair damage to the spacecraft while in orbit. Changes to the standard Shuttle mission profile gave future crews a chance of survival that the men and women aboard Columbia never had.

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Oscilloscope Art From Your Browser

February 1, 2018 by 13 Comments

Oscilloscope art is a fascinating pursuit in which waveforms are generated for the X an Y channels of an oscilloscope to draw pictures on its screen. It’s somewhat distinct from vector computer graphics of the type you might see in older arcade machines or the Vectrex console, in that while it uses a similar approach to creating a display it has a very different purpose. Sometimes these works can be breathtakingly beautiful animations, and other times maybe not so much.

If you’d like to explore the topic as a mild diversion, then maybe this Javascript oscilloscope art generator from [Neil Fraser] might be of interest. In around a hundred lines of code he’s created an in-browser scratchpad upon which a waveform can be drawn which will then be created as an audio signal on your computer’s soundcard. Hook up left and right to X and Y of your oscilloscope, and what you scribbled on the pad should pop up on the screen.

Draw it, see it on screen. Magic!
Draw it, see it on screen. Magic!

It’s an impressive piece of work that you can see in the video below or try for yourself, and your scribe’s Rigol was pressed into service to give it a go. After a bit of tweaking to find the right voltages and selecting slope triggering rather than edge triggering, we too were making squiggles appear on the screen.

It’s rather funny, he’s saved the best for last. As an afterthought, he also provides a link to another piece of his work, an oscilloscope clock in Javascript. If any of you would like to take this further and make a Javascript oscilloscope Wrencher, we’d love to make it famous.

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Sculptural Grade M&M Sorter

February 1, 2018 by 18 Comments

Sorting M&Ms is really only a major concern if you happen to be working on a Van Halen tour, but it’s a fun exercise nonetheless. It’s for this reason we see plenty of sorting projects come our way, varying from the breadboard and cardboard variety, all the way up to final university projects. Today, [Karl] has blessed us with their sculptural-grade offering, and the attention to detail is stunning.

The project has been in gestation in [Karl]’s mind, on and off, for 10 years or so. The big problem centered around reliably separating out one M&M at a time from a hopper of many. From time to time, [Karl] would speak with other builders using similar techniques to his failed experiments, who often reported that the secret to their machine’s reliability was… careful video editing. It was only when a parts sorter flashed across the Hackaday feed that [Karl] found the mechanism that would work to make his project a reality.

Now that the individual candies could readily be separated and fed through a machine, the rest of the project came together quickly. A color sensor was combined with servos and a stepper motor to duct M&Ms into separate flasks.

The real value of this build, however, is in the overall attention paid to the aesthetics of the final product. The device was built to be a kinetic sculpture, able to run reliably with the minimum of attention at the behest of even an untrained user. By carefully optimising the mechanisms inside and building an attractive enclosure, [Karl] has developed something we’d be proud to show off in a living room.