An Even Simpler Smartphone Garage Door Opener

We have seen smartphone garage door openers in the past, but [Lou’s] Hack is beautiful in its simplicity. His door opener tackles the problem without using computers, Arduinos, wireless modules or even any smartphone based applications. For this project all that is needed is a Bluetooth headset and a single transistor. The door opener uses the Samsung HM1100 Bluetooth headset, which [Lou] has done significant testing on to show that his creation is quite secure and will not open the door unexpectedly.

When this headset connects to a phone it produces a beep from the earbud, so [Lou] removed the speaker and replaced it with a transistor. Now he can use the voltage spike produced by the amplifier before the beep as his switching signal. By wiring the transistor in parallel with the door button inside his garage he is able to open the door wirelessly by connecting then right away disconnecting from the headset. This setup is apparently perfectly secure as the only way to initially link your phone with the headset is to be inside the garage. Check out the video after the break for build instructions and a demonstration.

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MIT’s ESuperbike Takes On The Isle Of Man

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While the Isle of Man typically plays host to an array of gas-powered superbikes screaming through villages and mountain passes at unbelievable speeds, the island’s TT Race is a bit different. Introduced in 2009 to offer a greener alternative to the traditional motorcycle race, organizers opened up the course to electric bikes of all kinds. In order to entice participants, they even put a £10k prize on the line for the first bike that completes the race with an average speed of 100 miles per hour or faster. While no one has claimed the prize just yet, that didn’t stop the MIT Electric Vehicle team from tossing their hat into the ring this year.

Their entry into the race is the brainchild of PhD student [Lennon Rodgers] and his team of undergrads. They first designed a rough model of the motorcycle they wanted to build in CAD, and through a professor at MIT sourced some custom-made batteries for their bike. Through a series of fortunate events, the team found themselves in front of BMW management, who donated an S1000RR racing bike to the project. After a good number of alterations, including the addition of an Arduino to control the bike, they were ready for race day.

While the team didn’t take the checkered flag, they did finish the race in 4th place. Their bike managed to complete the course with an average speed of 79 mph, which isn’t bad according to [Rodgers]. He says that for their first time out, he’s happy that they finished at all, which is not something every team can claim.

EReader Battery Never Goes Flat (in The Sun)

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Instructables user [flapke] has a Kobo eReader and wanted to add some solar cells to it in order to charge the battery for free. The modification is similar to others we have seen recently, though his work was done so well that it almost looks stock.

He started out by sourcing a pair of solar panels from DealExtreme that purported to supply 5.5v @ 80mA. Like most of us are inclined to do, he tested them before use and found that they actually put out around 50mA instead. While the performance was a bit off, they still fit his needs pretty well, as the charge current needed to be at or less than 100mA to avoid damaging the battery.

He opened the Kobo’s case, and carefully removed a section of the back panel to make room for the solar panels. Once they were soldered together in parallel, he wired them to the eReader’s battery through a Schottky diode to prevent the battery from draining.

While we think his solar modification is a great way to ensure that he never runs out of juice while reading by the pool, we would certainly add a bit of extra charge circuitry to ours to prevent damage to the battery. What do you think?

Turning Beer Cans Into Bells With 35kV

It looks like we now have another way to annoy ourselves with extremely high voltage.

The bells operate under the same principles as the electrostatic see-saw we covered last month. A voltage is applied to one can while the other can is grounded. An insulated pendulum is placed between each can, and with a little coaxing can be made to oscillate back and forth between the cans. As the pendulum touches the charged can, it is repelled as it gains the charge and moves to the grounded can. There, the charge is released and the cycle continues again. A homemade Cockcroft Walton multiplier is used to generate the +35kV needed to get the pendulum moving.

[Ben Franklin] invented the Franklin Bells while he was investigating electricity in the 1750s. Originally an extension of the kite & key experiment, the bells were historically used to warn of approaching thunderstorms – when the bells rang, the atmosphere was charged and lightning could strike. Even though the voltage between the bells is huge, very little current is drawn – the Oxford Electric Bells have been ringing since 1840 using the same electrostatic battery.

Man Spends 30 Years Helping Disabled Gamers

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Using our hands to manipulate game controllers is something most of us take for granted. However for quadriplegics, whose arms and legs are completely paralyzed, gaming becomes a nearly impossible task. One man has spent the last 30 years of his life trying to help quadriplegics once again “pick up” the controller and enjoy a few rounds of their favorite video games.

Retired aerospace engineer [Ken Yankelevitz] has been using his skills to create game controllers that can be easily used by disabled gamers, offering them for sale at cost. Starting with Atari joysticks in 1981, he has been perfecting his craft over the years, creating some 800 mouth-operated game controllers. As the systems and their controllers became more complex, so did [Ken’s] designs. His new Xbox and Playstation controllers use all manner of components, including sip-puff tubes and lip-activated buttons in order to allow users to access every single controller function.

Even as he approaches his 70th birthday, he is busy making controllers, though at a slower pace than he has in the past. He has said that he will continue making them for as long as he can, but at some point he will have to close up shop. This has disabled gamers worried that they may no longer have someone to turn to for custom controllers, though we hope someone steps in to fill the gap whenever that day comes.

Be sure to check out his site to take a look at his designs, what he has done for the disabled community is amazing.

Celebrating The Design Principles Behind Cellphones

Want to improve the finished look of your projects? There’s a lot you can learn by looking at the choices made in consumer electronics. [Bill Hammack] explores what is perhaps the most refined electronic device out there, the cell phone. Specifically, he discusses the seven design constraints that face every cellphone maker. They are: compactness versus usability, consumer preference, availability of energy, economic resources and available infrastructure, knowledge of materials, societal needs, and cultural constraints.

Anyone who’s whipped out their hacked-together project in a public space understands cultural constraints. Especially when forgetting your backpack in a public place can put the bomb squad of full alert these days. But aside from the anecdotal issues, [Bill’s] look at now-and-then cellphones really shows off the smart design that we enjoy thanks to the evolutionary process that went into what has become the wristwatch of the 21st century. See what he has to say in the video after the break.

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Excuse Me IPad, May I Cut In?

[LostSpawn] loves his clamshell keyboard for the iPad, but he had one major beef with the design. When the tablet is installed in the landscape orientation there’s no way to plug in a dock connector for charging or other uses. He pulled out the cutting tools and altered the case to meet his needs.

The case is a Rocketfish iCapsule which provides a Bluetooth keyboard when you need to do a lot of typing. The hard shell does a great job of protecting the iPad, but who wants to pull it out to charge it? The thing that we can’t believe is that there’s a slot milled in the other side of the bezel so that you can plug in headphones. How did they overlook the dock connector?

To add it himself, [LostSpawn] started by drilling a dotted line along the portion that he wanted to remove. He finished shedding material with a Dremel and then set about sanding it flat. To make sure it didn’t look too much like a hack he used Bondo to build up the working edge and then sanded and painted for a factory finish. Now he can plug in the cable or an SD card adapter like the one seen to the right of the keyboard.