Explore Low-Energy Bluetooth by Gaming

For several years now, a more energy-efficient version of Bluetooth has been available for use in certain wireless applications, although it hasn’t always been straightforward to use. Luckily now there’s a development platform for Bluetooth Low Energy (BLE) from Texas Instruments that makes using this protocol much easier, as [Markel] demonstrates with a homebrew video game controller.

The core of the project is of course the TI Launchpad with the BLE package, which uses a 32-bit ARM microcontroller running at 48 MHz. For this project, [Markel] also uses an Educational BoosterPack MKII, another TI device which resembles an NES controller. To get everything set up, though, he does have to do some hardware modifications to get everything to work properly but in the end he has a functioning wireless video game controller that can run for an incredibly long time on just four AA batteries.

If you’re building a retro gaming console, this isn’t too bad a product to get your system off the ground using modern technology disguised as an 8-bit-era controller. If you need some inspiration beyond the design of the controller, though, we have lots of examples to explore.

Continue reading “Explore Low-Energy Bluetooth by Gaming”

Quantum Computing For Computer Scientists

Quantum computing is coming, so a lot of people are trying to articulate why we want it and how it works. Most of the explanations are either hardcore physics talking about spin and entanglement, or very breezy and handwaving which can be useful to get a little understanding but isn’t useful for applying the technology. Microsoft Research has a video that attempts to hit that spot in the middle — practical information for people who currently work with traditional computers. You can see the video below.

The video starts with basics you’d get from most videos talking about vector representation and operations. You have to get through about 17 minutes of that sort of thing until you get into qubits. If you glaze over on math, listen to the “index array” explanations [Andrew] gives after the math and you’ll be happier.

Continue reading “Quantum Computing For Computer Scientists”

Custom Circuit Makes for Better Battery Level Display

Isn’t it always the way? There’s a circuit right out of the textbooks, or even a chip designed to do exactly what you want — almost exactly. It’s 80% perfect for your application, and rather than accept that 20%, you decide to start from scratch and design your own solution.

That’s the position [Great Scott!] found himself in with this custom LED battery level indicator. As the video below unfolds we learn that he didn’t start exactly from scratch, though. His first pass was the entirely sensible use of the LM3914 10-LED bar graph driver chip, a device that’s been running VU meters and the like for the better part of four decades. With an internal ladder of comparators and 1-kilohm resistors, the chip lights up the 10 LEDs according to an input voltage relative to an upper and lower limit set by external resistors. Unfortunately, the fixed internal resistors make that a linear scale, which does not match the discharge curve of the battery pack he’s monitoring. So, taking design elements from the LM3914 datasheet, [Great Scott!] rolled his own six-LED display from LM324 quad-op amps. Rather than a fixed resistance for each stage, trimmers let him tweak the curve to match the battery, and now he knows the remaining battery life with greater confidence.

Perhaps the 18650 battery pack [Great Scott!] is building is for the e-bike he has been working on lately. If it is, we’re glad to see that he spot-welded the terminals, unlike a recent e-bike battery pack build that may have some problems down the road.

Continue reading “Custom Circuit Makes for Better Battery Level Display”

Mademoiselle Pinball Table Gets Rock ‘n Roll Makeover

Once upon a time, there was a music venue/artist collective/effects pedal company that helped redefine industry in Williamsburg, Brooklyn. That place was called Death By Audio. In 2014, it suffered a death by gentrification when Vice Media bought the building that DBA had worked so hard to transform. From the ashes rose the Death By Audio Arcade, which showcases DIY pinball cabinets made by indie artists.

Their most recent creation is called A Place To Bury Strangers (APTBS). It’s built on a 1959 Gottlieb Mademoiselle table and themed around a local noise/shoegaze band of the same name that was deeply connected to Death By Audio. According to [Mark Kleeb], this table is an homage to APTBS’s whiz-bang pinball-like performance style of total sensory overload. Hardly a sense is spared when playing this table, which features strobe lights, black lights, video and audio clips of APTBS, and a fog machine. Yeah.

[Mark] picked up this project from a friend, who had already cut some wires and started hacking on it. Nearly every bit of the table’s guts had to be upgraded with OEM parts or else replaced entirely. Now there’s a Teensy running the bumpers, and another Teensy on the switches. An Arduino drives the NeoPixel strips that light up the playfield, and a second Uno displays the score on those sweet VFD tubes. All four micros are tied together with Python and a Raspi 3.

If you’re anywhere near NYC, you can play the glow-in-the-dark ball yourself on July 15th at Le Poisson Rouge. If not, don’t flip—just nudge that break to see her in action. Did we mention there’s a strobe light? Consider yourself warned.

Want to get into DIY pinball on a smaller scale? Build yourself a sandbox and start playing.

Continue reading “Mademoiselle Pinball Table Gets Rock ‘n Roll Makeover”

This Is Your Last Chance To Design The Greatest In Power Harvesting

This is your last weekend to get your project together for the Power Harvesting Challenge in this year’s Hackaday Prize. We’re looking for projects that harvest energy from the ether, and power electronics from solar, thermal, wind, light, or random electromagnetic fluctuations. Is it going to save the world? Maybe, but it’s a great excuse to build some really cool electronics. If you have an idea in mind, this is your last weekend to enter it in the Power Harvesting Challenge.

The Hackaday community has thrown itself full-force into the Hackaday Prize, and there are hundreds of projects entered in this year’s Prize. Next week, we’ll choose the top twenty projects entered during the Power Harvesting Challenge to advance to the finals. Each of those twenty projects will be awarded $1,000 and be in the running to win the Grand Prize of $50,000 and four other top cash prizes.

This is your last chance to get in on the Power Harvesting Challenge in this year’s Hackaday Prize. For this challenge, we’re looking for projects that harvest energy from any source. It could be a module, or as a distinct design easily incorporated into other builds. Don’t wait — start your entry now.

The Power Harvesting Challenge ends a 07:00 AM PDT on July 16th. Afterwards, we’ll be continuing on into Human-Computer Interface and Musical Instrument Challenges. This is your shot to get your project in the finals in the Hackaday Prize. Don’t miss out!

ERRF 18: New Products Make their Debut

While ostensibly the purpose of the recent East Coast RepRap Festival (ERRF) was to celebrate the 3D printing community and culture, it should come as no surprise that more than a few companies decided to use the event as an opportunity to publicly launch new products. Who can blame them? It’s not as if every day you have a captive audience of 3D printing aficionados; you might as well make the best of it.

Many creations were being shown off for the first time at ERRF, and we surely didn’t get a chance to see them all. There was simply too much going on at any given time to be sure no printed stone was left unturned. But the following printers, filaments, and accessories caught our attention long enough to warrant sharing with the good readers of Hackaday.

Keep in mind that much of this information is tentative at best, and things could easily change between now and when the products actually go on sale. These events serve as much as a sounding board for new products as they do a venue for advertising and selling them, so feedback received from show attendees may very well alter some of these products from what we saw at ERRF.

Continue reading “ERRF 18: New Products Make their Debut”

Supersize DIY R/C Servos From Windscreen Wipers

We’re all familiar with the experience of buying hobby servos. The market is awash with cheap clones which have inflated specs and poor performance. Even branded servos often fail to deliver, and sometimes you just can’t get the required torque or speed from the small form factor of the typical hobby servo.

Enter [James Bruton] and his DIY RC servo from a windscreen wiper motor. Windscreen wiper motors are cheap as chips, and a classic salvage. The motor shaft is connected to a potentiometer via a pulley and some string, providing the necessary closed-loop feedback. Instead of using the traditional analog circuitry found inside a servo, an Arduino provides the brains. This means PID control can be implemented on the ‘duino, and tuned to get the best response from different load characteristics. There’s also the choice of different interfacing options: though [James]’ Arduino code accepts PWM signals for a drop-in R/C servo replacement, the addition of a microcontroller means many other input signal types and protocols are available. In fact, we recently wrote about serial bus servos and their numerous advantages.

We particularly love this because of the price barrier of industrial servomotors; sure, this kind of solution doesn’t have the precision or torque that off-the-shelf products provide, but would be sufficient for many hacks. Incidentally, this is what inspired one of our favourite open source projects: ODrive, which focuses on harnessing the power of cheap brushless motors for industrial use.

Continue reading “Supersize DIY R/C Servos From Windscreen Wipers”