Cyclists Use Tiny Motors to Cheat

Blood doping is so last decade! The modern cyclist has a motor and power supply hidden inside the bike’s frame.

We were first tipped off to the subject in this article in the New York Times. A Belgian cyclocross rider, Femke Van den Driessche, was caught with a motor hidden in her bike.

While we don’t condone sports cheating, we think that hiding a motor inside a standard bike is pretty cool. But it’s even more fun to think of how to catch the cheats. The Italian and French press have fixated on the idea of using thermal cameras to detect the heat. (Skip to 7:50 in the franceTVsport clip.) We suspect it’s because their reporters recently bought Flir cameras and are trying to justify the expense.

The UCI, cycling’s regulatory body, doesn’t like thermal. They instead use magnetic pulses and listen for the characteristic ringing of a motor coil inside the frame. Other possibilities include X-ray and ultrasonic testing. What do you think? How would you detect a motor inside a bike frame or gearset?

Camera Slider Helps get the Shots with E-Waste Controller

A camera slider is an accessory that can really make a shot. But when your business is photography rather than building camera accessories, quick-and-dirty solutions often have to suffice. Thus the genesis of this camera slider controller.

The photographer in question in [Paulo Renato], and while his passion may be photography, he seems to have a flair for motorized dollies and sliders. This controller is a variable-speed, reversible, PIC-based design that drives an eBay gearmotor. The circuit lives on a scrap of perfboard, and it along with batteries and a buck converter are stuffed into the case-modded remains of an old KVM switch. Push buttons salvaged from another bit of e-waste act as limit switches, and a little code provides the magic. We like the hacked nature of the controller, but we wonder about the wisdom of using the former KVM’s USB ports to connect the controller to the drivetrain; it’s all fun and games until you plug a real USB device into it. In sum, though, a nice build with nice results. Check out his other videos for more on the mechanicals.

Camera slider rigs aplenty have graced our pages, including one made mostly of wood and one controlled by a fancy iPad app.

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A 3D-Printed Engagement Ring

[Hans Peter] had reached the moment of popping the question. Going down on one knee and proposing to his girlfriend, the full romantic works.

He’s a brave man, [Hans]. For instead of heading for the jeweller’s and laying down his savings on something with a diamond the size of a quail’s egg he decided that his ring should contain something very much of him. So he decided to 3D print a ring and embed a slowly pulsing LED in it. He does mention that this ring is a temporary solution, so perhaps his soon-to-be-Mrs will receive something sparkly and expensive in due course.

To fit his LED and flasher in such a small space he used a PIC10F320 microcontroller that comes in a SOT-23-6 package. This was chosen because it has a handy PWM output to pulse the LED rather than flash it. This he assembled dead-bug style with an 0603 LED, and a couple of hearing aid batteries to power the unit. He has some concerns about how long the hearing aid batteries will power the device, so as he wrote he had better hurry and get on his knees. (He informs us in his tip email that she said yes.)

Surprisingly we’ve covered quite a few engagement ring builds over the years. Closest to this one is an LED ring powered by an induction coil, but we’ve also featured machined titanium rings and some rather nice cast rings.

BeagleBone Pin-Toggling Torture Test

Benchmarks often get criticized for their inability to perfectly model the real-world situations that we’d like them to. So take what follows in the limited scope that it’s intended, and don’t read too much into it. [Joonas Pihlajamaa]’s experiments with toggling a hardware pin as fast as possible on different single-board computers can still show us something.

The take-home result won’t surprise anyone who’s worked with a single-board computer: the higher-level interfaces are simply slow compared to direct memory-mapped GPIO access. But really slow. We’re talking around 5 kHz from Python or any of the file-based interfaces to the pins versus 3 MHz for direct access. Worse, as you’d expect when a non-realtime operating system is in the middle, there are glitches on the order of ten milliseconds with all the file-based methods.

This test only tells us so much, though, and it’s not really taking advantage of the BeagleBone Black’s ace in the hole, the PRUs — onboard hardware processors that bring real-time IO capabilities to the system. We’d like to see a re-write of the code to take advantage of libpruio, for instance. A 20 MHz square wave is a piece of cake with the PRUs.

Of course, it’s not interacting, which is probably in the spirit of the benchmark as written. But if raw hardware speed on a BeagleBone is the goal, it’s likely that the PRUs are going to feature prominently in the solution.

Desktop Siege Weapon: Fireball Cannon

Looking for a harmless way to really step up your office warfare game? Why not build a nitrocellulose desktop cannon!?

On of our favorite science DIY YouTube channels, [NightHawkInLight] shows us how he made this awesome cannon — with interchangeable cannon cartridges! It even has a bit of a steampunk feel to it.

Nitrocellulose, or flash cotton as it’s more commonly known, is used by magicians for fireball magic tricks. Similar to flash paper, it burns up very fast and leaves almost no ash or residue. Creating the fireball effect is as simple as igniting it inside a tube — expanding gases take care of launching it out quite violently.

All the action is in the 3/4″ copper tube cartridges that come complete with home-made glow-plugs made from nichrome wire harvested from a broken hairdryer. These interchangeable cartridges allow [NightHawkInLight] to load up ahead of time and fire them off in quick succession.

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Box ‘o Bangs, a 2,180J Capacitor Bank

What happens when you wire up 16 capacitors? Sixteen 2500V 40uF capacitors to be precise… [Lemming] calls it the Box ‘O Bangs. Theoretically it outputs 4000A at 2500V for a split second.

They bought the capacitors off of eBay, and they appear to be good quality BOSCH ones, straight from Germany. They were apparently used for large-scale industrial photo-flashes, but who knows since they’re from eBay.

Soldering it all together proved to be a challenge, as once they realized just how many amps this thing was going to put out, they needed some thick wire. It looks like about 2ga wire, which, spoiler alert, still isn’t enough for 4000A — but since it’s only for a split second it seems to do fine.

Once everything was built, it was time for some scientific tests — what can we put between the leads to explode? Stay tuned for some slow-motion glory.

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Flappy Bird on an… E-Cigarette?

Okay, now we’ve seen it all. Someone put the effort in to port Flappy Bird… to run on an e-cigarette. An eVic-VTC Mini to be precise. So now, between puffs, you can play one of the most frustrating games ever.

The SDK for the e-cig is available on GitHub, which was provided by a group of Redditors last year. If you’re interested in the game, and happen to have this model of e-cig, [Bank] has provided download and flashing instructions in the description of the YouTube video.

As one Reddit user points out:

“Your scientists were so preoccupied with whether or not they could, they didn’t stop to think if they should.”

To which the creator, [Balázs Bank], responded with the download links to install it yourself. Has science gone too far?

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