Why Wait? Just Plate Your Own PCB Vias

November 2, 2017 by Kristina Panos 34 Comments

[Jan Mrázek] is a pro when it comes to rolling his own PCBs. He can crank out a 6/6 mil double-sided PCB in 45 minutes flat. As a challenge to his prowess, he decided to experiment with plating through-hole PCBs at home, because sometimes you just can’t wait for China to deliver the goods.

The key here is to make a non-conductive surface—the walls of holes drilled in a sheet of copper clad–conductive. While there are some established ways of doing this at home, the chemicals are difficult to source. When his local supplier started stocking colloidal graphite paint, which is used to prevent ESD and fix non-working remote control buttons, he decided to try it.

[Jan] drilled up a board with holes ranging from 0.1mm up to 8mm, polished it, and gave it an acetone bath. He sprayed each side with graphite and cured it at 100 °C for 20 minutes. At this point, wall hole resistance measured 21 Ω. [Jan] wet-sanded away the graphite and set up an electroplating bath. Right away, he could see a layer of copper forming on the holes. After 90 minutes, he polished the board again and separated the vias to prepare for the real test: solder. This time, every hole except the smallest size reported a resistance of 0.1 Ω. But they all sucked solder through the vias, making this experiment a success.

[Jan] concluded that this is a simple and effective process, but is rarely worth the effort. We wonder how the simplicity of this method compares to drilling wells instead of holes, filling them with conductive ink, and then drilling the rest of the via.

Via [Dangerous Prototypes]

DIY Pyrography Power Supply

November 2, 2017 by Kristina Panos 25 Comments

Ever wanted to try your hand at wood burning? If you already threw away your first soldering iron—you know the one: plugged straight in to the wall, no temperature control, came with a thick piece of tin foil to rest it on—don’t despair. Pyrography pens don’t cost that much. The variable power supply they plug into, though: that’s another story. Those cost more than they probably should.

[td0g] took the plunge into pyrography a while back, and wanted to build his own controller from an old ATX power supply. Why not? It should be more than capable of doing the job. Even the most heavy-duty pyrography pens only draw 10A, and the 3.3V line showed to be rated for 30A. All [td0g] had to do was add a PWM with a MOSFET and a ‘Tiny85.

The project nearly became Fail of the Week fodder after [td0g] saw huge voltage spikes across the MOSFET. A 47kΩ resistor took care of those, and a heat sink salvaged from the junk bin will prolong the transistor’s life. [td0g] added a push button that cycles through five heat settings, and an LED to show the status. After that, all he had to do was add a male RCA input to connect the pens he already has.

Okay, so you wouldn’t be caught dead dropping money on some fancy power supply for this new hobby. Don’t want to buy pens, either? Roll your own from a plasma arc lighter.

Hackaday Prize Entry: Volturnus ROV Rules The River

November 1, 2017 by Kristina Panos 2 Comments

Water is kind of like information: both are a vital part of life and are found all around us. But not all water or information is healthy. Much of it may look harmless, but is actually polluted. A staggering number of people in the world have no access to fresh, clean water. ROVs can collect samples and detect pollution, but commercial types are way too expensive for the legions of people who need them.

UV light reveals the presence of optical brightening agents in a sample of lake water.

[allai5] wants to be the catalyst for change. She’s the president of Rogue Robotics, a group of high school students throughout central New Jersey who have pooled their talents to design and build a simple, open-source ROV that’s affordable, repeatable, and environmentally friendly. The team uses Volturnus ROV to collect water samples and UV light to determine the presence of a general type of pollutant known as optical brightening agents (OBAs). This is the stuff they add to laundry detergents and copy paper to whiten the fibers’ appearance. By design, OBAs fluoresce brightly under UV light. After soaking a cotton pad in water sample, it’s easy to see if OBAs are present.

At 12″ x 12″ x 18″, Volturnus ROV is compact enough to explore most of the nooks and crannies of any body of water. It moves under the power of three thrusters—500 GPH bilge pump motors driven by a pair of L298N controllers—and is controlled by an Arduino Mega using a wireless joystick. The driver of the ROV navigates the drink through the eyes of a waterproof car back-up camera whose feed is flipped with a Python script.

Volturnus ROV is not a one-stop solution for dealing with marine pollution. The team would like to add filtration in the future and move the electronics to the bottom so it can go faster. Rogue Robotics’ aim has always been to make an ROV that does a few things well. Right now, it’s an excellent jumping-off point for awareness and blueprint for action. Find your inspiration after the break.

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Rita Levi-Montalcini Had Nerves Of Steel

October 31, 2017 by Kristina Panos 26 Comments

When we think of role models, it’s easy to categorize them narrowly on the basis of their skill set. We might say that he’s a great mathematician, or that she is an excellent chemist. Some role models are admirable on a deeper, human level. These are the kinds of heroes who obliterate all the obstacles dropped in front of them to tirelessly pursue their interests and devote their lives to doing the kind of stuff that makes the world better for everyone.

Italian Nobel Laureate Rita Levi-Montalcini is this kind of role model. Her scientific curiosity and unconventional thinking led her to discover nerve growth factor (NGF), a naturally occurring protein which we now know is responsible for nerve growth and regulation. Rita’s discovery provided great insight into the way the nervous system develops. The discoveries that she made underlie much of modern research into neurologically degenerative diseases like Alzheimer’s and cancer, and NGF is used experimentally the treatment of both.

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Water Slide + Ferris Wheel = SlideWheel

October 29, 2017 by Kristina Panos 30 Comments

This might be German engineering at its funnest. [Wiegand Maelzer GmbH] have created a new type of amusement park ride that combines the thrill of a water slide with the gentle revolutions of a Ferris wheel.

Inspired by the wish of a young Swiss boy in 2012, the whimsical feat of engineering known as the SlideWheel was realized this year. This is isn’t quite the giant sloshing drowning machine it appears to be on first blush, though. It begins and ends at the same shallow pool, where three- and four-person rafts are lifted into the ride by conveyor belt. What happens next is difficult to describe. It’s easier just to watch the first-person video below that demonstrates the pendulum-like motion that comes from floating while rotating.

SlideWheel moves at a modest 3 RPM, though this can be adjusted. Travel speed through the tube maxes out at 40 KPH/ 25 MPH, but will vary depending on the raft’s location, the position of the wheel, and gravity. The ride can handle up to three rafts at a time and delight 720 people per hour. A trip through the tube lasts a mere two minutes, but all those who’ve tried it say the experience seems much longer. [Wiegand Maelzer] have already received a few orders and are working on a dry version for malls and indoor amusement parks.

Not enough of an engineering feat, you say? Here’s a car-juggling robot.

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SimpleSumo Bots Teach More Than Fighting

October 28, 2017 by Kristina Panos 2 Comments

[MechEngineerMike] wrote in to share the enthusiasm over SimpleSumo, a series of open source, customizable robots he designed for mini-sumo battling and much more. For the unfamiliar, mini-sumo is a sport where two robots try to push each other out of a ring. [Mike]’s bots are simplified versions designed for education.

[Mike] was inspired by a video of some kids building mini-sumo bots who were doing anything and everything to personalize them. He vowed to make his own affordable, easy-to-build bots with education firmly in mind. His other major requirement? They had to be as easily customizable as that one potato-based toy that eventually came with a bucket of parts. As of this writing, there are 34 interchangeable accessories.

[Mike]’s first idea was to build the bots out of custom 3D-printed building blocks. He soon found it was too much work to print consistent blocks and switched to a modular cube-like design instead. SimpleSumo bots can do much more than just fight each other. [Mike] has written programs to make them flee from objects, follow lines, find objects and push them out of the ring, and beep with increasing frequency when an object is detected.

The bots are completely open source, but [Mike] sells kits for people who can’t print the parts themselves. He’s made a wealth of information available on his website including links to outside resources about mini-sumo, Arduino, programming, and 3D design. How about a complete series of assembly videos? First one is after the break. Don’t know how to build a battle ring? He’s got that covered, too.

For a sumo bot that’s more brains than brawn, check out Zumo Red, the smart sumo.

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Hazardous Dollhouse Teaches Fire Safety

October 22, 2017 by Kristina Panos 20 Comments

Fire safety is drilled into us from a young age. And for good reason, too, because fire hazards are everywhere in the average home. Even a small fire can turn devastatingly dangerous in a matter of minutes. But how do you get kids to really pay attention to scary (and often boring) adult concepts? You can teach a kid to stop, drop, and roll until you’re blue in the face and still might not drive home the importance of fire prevention. Subjects like this call for child-sized visual aids that ignite imaginations.

That’s exactly what firefighters in Poznań, Poland did in collaboration with mlabs, a local software company. They built a mobile, interactive fire safety education tool that simulates common household fire hazards in great detail (translated). This is easily the most tricked-out dollhouse we’ve ever seen. The many different hazard scenarios are controlled via touchscreen using a custom-built application. At the tap of a button, the house becomes a total death trap. The lamp-lit hazards glow realistically and with varied intensity, and there is actual smoke coming out of them that triggers smoke detectors. Cameras embedded throughout the house provide a first-person view of the terror on a nearby monitor.

Almost no room is safe for the figurine family that lives inside this intricately detailed 1:12 scale dwelling. Dad’s in the kitchen standing idly by while food scorches on the stove. Grandma’s sitting on her bed upstairs, her forgotten cigarette burning a hole in the duvet. Daughter is overloading the electrical outlets in her bedroom with all her gizmos. Smoldering coals have spilled out from the toppled stove in the utility room.

This isn’t the first smart dollhouse we’ve seen, but it’s probably the most intriguing. The fire safety dollhouse was on display this week at POL-EKO-SYSTEM, an annual environmental fair in Poznań. Nowhere near Poland? Check out the video after the break.

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