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[Johna and Justin] are working to take the emotion out of playing the market. They built this piggy bank which automatically purchases stock when your coinage totals the cost of a single share. That’s right, just turn the selector to one of your three chosen stocks (Google, Facebook, and Apple are used in this example) and plug in some coins. The bank counts your money, compares it to the current online stock price, and pulls the trigger if you have enough dough. You can check out a demo clip after the jump.

The hardware is rather simple thanks to Adafruit’s programmable multi-coin acceptor. It handles the cash and it’s pretty easy to interface with the Arduino which handles the rest of the work. It connects to a computer via USB, depending on a PHP script to poll the current price. We dug through the code repository just a bit but didn’t find the snippet that does the actual stock purchase. Whether or not they actually implemented that, it’s certainly an interesting concept.

Filed under: lifehacks

Maine-based Grain Surfboards is a small maker-run company on the coast that hand-makes sustainably cut, locally milled white cedar wooden surfboards. Aside from their dedication to environmental responsibility, what sets Grain apart is that they also offer DIY surfboard kits and a variety of surfboard-building classes. Their newest undertaking is [...]

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Despite the large number of categories of robots here at RoboGames, the resounding sounds of metal on metal and cheers from the crowd keep drawing us back to the combat arena. We were immediately surprised by the variety of locations and backgrounds these teams come from, whether it's a High School from across the country, a local engineer working in his garage, or a robotics team from Brazil.

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This is the second of a three-part series on the Internet of Things with Atmel’s Tom Vu and Internet of Things Council member Michael Koster. Today: What is the IoT Toolkit?

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Interesting Instructable from Dr. Patrik D'haeseleer, Harvard-trained computational biologist and denizen of Sunnyvale biotech hackerspace BioCurious. Bioprinting, which is basically 3D printing with living cells, has been much in the news lately, with breathless tales of fully 3D-printed living organs and replacement body parts. There is of course a fair bit of hype going on here, but also, at the core, a body of very interesting applied research.

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The season's final Open Make @ the Hall ends on a tiny note. Bring your little things and get inspired by the big impact your mini-creations can have. The fun starts tomorrow, April 20, and runs from 10am-2pm.

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“To not be amazed is to be numb to the technology of our day.” From the editors of MAKE magazine, The Maker Pro Newsletter is about the impact of makers on business and technology. Our coverage includes hardware startups, new products, incubators, innovators, along with technology and market trends.

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DIY.org is an online community for young makers to share their skills and projects, and to be inspired and learn to make new creations. This year at Maker Faire Bay Area, they will be providing the supplies and space for Cardboard Village, a place where kids can collaborate to build their own community using cardboard. If you're planning to attend Maker Faire, stop by and check out the progress!

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The Monkey's Paw is an antiquarian bookstore in Toronto that now also houses the world’s first randomizing vending machine for old books — the Biblio-mat.

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Imagine the carnage that ensues when you pit two 200+ lb. robots against each other, often with weapons that spin at around 3500 rpm. The noise level and adrenaline both run high as they bang away at each other. Intern Coordinator Sam Freeman and I are at RoboGames to witness not only the combat, but all sorts of other robotics events as well. We only got here a little while ago, but have already been fascinated by the great stuff we've seen.

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[Karl Lunt] wrote in to share his LED firefly project. His goals for the project were to develop a low-power, low parts count module that can sense when it’s dark and then mimic the blinking patterns you’d associate with its biological namesake.

We like his design which uses a coin cell battery holder as the chassis for the project. The ATtiny13 driving the hardware is held in place by the two power wires. This lets him flash new firmware by rotating the chip and plugging in a little adapter he build. The LED connection might look a bit peculiar to you. It has a resistor in parallel, which doesn’t satisfy the normal role of a current limiting resistor. That’s by design. [Karl] is driving the LED without any current limiting, which should be just fine with the 3V battery and short illumination time of the diode. The resistor comes into play when he uses the LED as a light sensor. Past firefly projects included light dependent resistors to detect light and synchronize multiple units. [Karl] is foregoing the LDR, using the LED with a resistor in parallel to combat the capacitive qualities of the diode. As we mentioned, this senses ambient light, but we’d love to see an update that also uses the LED to synchronize a set of the devices.

Filed under: led hacks, Microcontrollers

[Dr. Iguana's] experience moving from projects powered by disposable Alkaline cells and linear regulators to recycled Lithium Ion cells using the buck regulators seen above might serve as an inspiration to make the transition in your own projects.

The recycled cells he’s talking about are pulled out of larger battery packs. As we’ve seen in the past, dead battery packs for rechargeable tools, laptops, etc., are often plagued by a few bad apples. A small number of dead cells can bork the entire battery even though many perfectly usable cells remain. Once he decided to make the switch it was time to consider power regulation. He first looked at whether to use the cells in parallel or series. Parallel are easier to charge, but boosting the voltage to the desired level ends up costing more. He decided to go with cells in series, which can be regulated with the a less expensive buck converter. In this case he made a board for the RT8289 chip. The drawback of this method requires that you monitor each cell individually during charging to ensure you don’t have the same problem that killed the battery from which you pulled these good cells.

Filed under: parts

Ever battled SRAM limitations with your sketch on the Arduino Uno? Decided reluctantly to break out an Arduino Mega, and suffer with the resulting shield incompatibilities? Then the new Goldilocks board might be just what you're looking for in a micro-controller.

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Kevin Fitzpatrick both lives and works in his Transit Connect for nearly a quarter of the year. He has extensively modified his vehicle to provide office space, sleeping quarters, storage for gear, a mini-fridge, and even a sink with gray and potable water.

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How many times can you put two LEGO pieces together and take them apart again before they wear out? The answer is 37,112. At least that’s the number established by one test case. [Phillipe Cantin] was interested in this peculiar question so he built the test rig above to measure a LEGO’s lifespan.

The hacked together apparatus is pretty ingenious. It uses two servo motors for testing, each driven by the Arduino which is logging the count on an SD card. One of the two white LEGO parts has been screwed onto an arm of the upper servo. That servo presses down onto the mating piece which is sitting inside that yellow band. Look close and you’ll realize the yellow is the handle end of an IC puller. When the post on the lower servo is moved toward one arm of the puller it grips the lower LEGO piece tightly so that the upper servo can pull the two apart. In addition to the assembly and disassembly step there’s a verification step which raises the mated parts so that a reflectance sensor can verify that they’re holding together. [Phillipe] let the rig run for ten days straight before the pieces failed.

Don’t miss his video description of the project after the break.

[via Reddit]

Filed under: arduino hacks, toy hacks

I've had the intention to cover and post about my favorite artists for a long time now, finally getting off my lazy butt to do it. No better way to kick it off, than with a living legend, James Gurney. James is best known for the Dinotopia series, where he combine an amazing world of fantasy, and the prehistoric natural world, sparking the imagination of millions of kids and adults alike. Gurney’s not only a creative genius, but also a true master of light, composition… .. he’s just a bad ass painter, I don’t know how else to say it. His books are among my favorites, where he shares his secrets sauce. His approach, breaking down of the basics, to advanced painting techniques and theories, are simply invaluable. I was lucky enough to get some Q & A with Mr.Dinotopia himself, and here it is!

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Tomorrow kicks off the 10th year of RoboGames, a three-day extravaganza of robots and technology. The dozens of competitions cover everything from line following and fire fighting to weight lifting and mech warfare.

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This is first of a three-part series on the Internet of Things with Atmel's Tom Vu and Internet of Things Council member Michael Koster. Part 1: Inspiration and Requirements.

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Sculptor George W. Hart recently designed and constructed two five-fold symmetrical sculptures with his "Crystal Flowers in Halls of Mirrors: Mathematics Meets Art and Architecture” class at Aalto University in Helsinki.

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This pulse oximeter is so simple and cheap to build it’s almost criminal. The most obvious way to monitor the output of the sensor is to use an oscilloscope. The poor-man’s stand-in for that is a sound card, which is what [Scott Harden] demonstrates in his write-up.

It uses a concept we’ve seen a few times before. The light from an LED shines through your finger and is measured on the other side by a phototransistor. It’s that light grey plastic thing you see on a patient’s finger when they’re in the hospital. [Scott] went with a common wooden clothes pin as a way to mount and align the sensor with your finger. It is monitored by the simplest of circuits which uses just one chip: an LM324 op-amp. There are three basic stages which he explains well in the video after the jump. The incoming signal is decoupled before being fed to the first amplifier stage. From there it is fed to an adjustable low-pass filter to help eliminate 60Hz noise from AC power in the room. The last stage amplifies the signal again while using another low-pass filter in parallel.

Filed under: Medical hacks