Be the Firebender You Want to See in the World

Always wanted to be a citizen of Fire Nation? Here’s one way to ace the citizenship exam: punch-activated flaming kung fu gauntlets of doom.

As with all the many, many, many flamethrower projects we’ve featured before, we’ve got to say this is just as bad an idea as they are and that you should not build any of them. That said, [Sufficiently Advanced]’s wrist-mounted, dual-wielding flamethrowers are pretty cool. Fueled by butane and containing enough of the right parts for even a minimally talented prosecutor to make federal bomb-making charges stick, the gauntlets each have an Arduino and accelerometer to analyze your punches. Wimpy punch, no flame — only awesome kung fu moves are rewarded with a puff of butane ignited by an arc lighter. The video below shows a few close calls that should scare off the hairy-knuckled among us; adding a simple metal heat shield might help mitigate potential singeing.

Firebending gloves not enough to satisfy your inner pyromaniac? We understand completely.

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Hackaday Prize Entry: Stroke Rehabilitation Through Biofeedback

Students at Purdue University’s Weldon School of Biomedical Engineering created ExoMIND, an Arduino-powered glove that helps a stroke victim recover by tracking the range of motion the patient experiences.

A set of 7 accelerometers in the fingers, wrist, and forearm track the range of movements the patient is experiencing with that hand. An accelerometer on the back of the hand serving as a reference. Meanwhile, an EMG sensor working with a conductive fabric sleeve to measure muscle activity. The user follows a series of instructions dished out by an interactive software program, allowing the system to test out the patient’s range of motion at the beginning of the regime as well as to record whether any improvement was noted at the end. The data is used by a physical therapist to personalize the treatment plan. The interactive program also raises the possibility of patients self-directing their exercises with the ExoMIND telling them how to adjust their motion to get the most out of the experience.

Produced as part of the university’s MIND Biomedical Engineering Club, the ExoMIND prototype was designed by three interdisciplinary teams focusing on electronics, materials, and programming, respectively.

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MEMS: The Biggest Word in Small

What’s tiny and on track to be worth $22 billion dollars by 2018? MEMS (Micro Electrical Mechanical Systems). That’s a catch-all phrase for microscopic devices that have moving parts. Usually, the component sizes range from 0.1 mm to 0.001 mm, which is tiny, indeed. There are some researchers working with even smaller components, sometimes referenced as NEMS (Nano Electrical Mechanical Systems).

Resonant Cantilever by [Pcflet01], CC BY-SA 3.0
MEMS have a wide range of applications including ink jet printers, accelerometers, gyroscopes, microphones, pressure sensors, displays, and more. Many of the sensors in a typical cell phone would not be possible without MEMS. There are many ways that MEMS devices are built, but just to get a flavor, consider the cantilever (see right), one of the most common MEMS constructions.

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Hackaday Prize Entry: Analyzing and Controlling Hand Tremors

For the millions of people suffering from Parkinson’s and other causes of hand tremor, there is new hope in the form of [mohammedzeeshan77]’s entry into the Hackaday Prize: a glove that analyzes and controls the tremors.

The glove uses an accelerometer and a pair of flex sensors to determine the position of the hand as it oscillates. A Particle Photon crunches the raw data to come up with the frequency and amplitude of the tremors and uploads it to the cloud for retrieval and analysis by medical staff.

Hand tremors can vary in frequency and severity depending on the cause. Some are barely perceptible movements, and others are life-disrupting shakes. By analyzing the frequency and amplitude of these tremors, doctors can better understand a patient’s condition.

The best part of this glove is that it also provides immediate relief to the wearer by stabilizing the hand. A rapidly spinning super precision gyroscope counteracts the tremor oscillations as it tries to maintain its position. The last time we saw innovation like this, it came with a set of attachments.

Low-cost Drift Buoy Plies the Atlantic for Nearly a Year

Put a message in a bottle and toss it in the ocean, and if you’re very lucky, years later you might get a response. Drop a floating Arduino-fied buoy into the ocean and if you’ve engineered it well, it may send data back to you for even longer.

At least that’s what [Wayne] has learned since his MDBuoyProject went live with the launching of a DIY drift buoy last year. The BOM for the buoy reads like a page from the Adafruit website: Arduino Trinket, an RTC, GPS module, Iridium satellite modem, sensors, and a solar panel. Everything lives in a clear plastic dry box along with a can of desiccant and a LiPo battery.

The solar panel has a view through the case lid, and the buoy is kept upright by a long PVC boom on the bottom of the case. Two versions have been built and launched so far; alas, the Pacific buoy was lost shortly after it was launched. But the Atlantic buoy picked up the Gulf Stream and has been drifting slowly toward Europe since last summer, sending back telemetry. A future version aims to incorporate an Automatic Identification System (AIS) receiver, presumably to report the signals of AIS transponders on nearby ships as they pass.

We like the attention to detail as well as the low cost of this build. It’s a project that’s well within reach of a STEM program, akin to the many high-altitude DIY balloon projects we’ve featured before.

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Scratch-built Camera Gimbal for Photographer with Cerebral Palsy

We so often hack for hacking’s sake, undertaking projects as a solitary pursuit simply for the challenge. So it’s nice to see hacking skills going to good use and helping someone out. Such was the case with this low-cost two-axis handheld camera gimbal intended to help a budding photographer with a motion disorder.

When [Tadej Strah] joined his school photography club, a fellow member who happens to have cerebral palsy needed help steadying cameras for clean shots. So rather than shell out a lot of money for a commercial gimbal, [Tadej] decided to build one for his friend. A few scraps of aluminum bar stock were bent into the gimbal frames and camera mount. Two hobby servos take care of the pitch and roll axes, controlled by an Arduino talking to an MPU-6050. Mounted to a handle from an angle grinder with the battery and electronics mounted below, the gimbal looks well-balanced and does a good job of keeping the camera level.

Hats off to [Tadej] for pitching in and solving a real world problem with his skills. We like to see people helping others directly, whether it’s building a gyroscopic spoon for Parkinson’s sufferers or vision enhancement for a nearly blind adventurer.

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This WAV File Can Confuse Your Fitbit

As the devices with which we surround ourselves become ever more connected to the rest of the world, a lot more thought is being given to their security with respect to the internet. It’s important to remember though that this is not the only possible attack vector through which they could be compromised. All devices that incorporate sensors or indicators have the potential to be exploited in some way, whether that is as simple as sniffing the data stream expressed through a flashing LED, or a more complex attack.

Researchers at the University of Michigan and the University of South Carolina have demonstrated a successful attack against MEMS accelerometers such as you might find in a smartphone. They are using carefully crafted sound waves, and can replicate at will any output the device should be capable of returning.

MEMS accelerometers have a microscopic sprung weight with protruding plates that form part of a set of capacitors. The displacement of the weight due to acceleration is measured by looking at the difference between the capacitance on either side of the plates.

The team describe their work in the video we’ve put below the break, though frustratingly they don’t go into quite enough detail other than mentioning anti-aliasing. We suspect that they vibrate the weight such that it matches the sampling frequency of the sensor, and constantly registers a reading at a point on its travel they can dial in through the phase of their applied sound. They demonstrate interference with a model car controlled by a smartphone, and spurious steps added to a Fitbit. The whole thing is enough for the New York Times to worry about hacking a phone with sound waves, which is rather a predictable overreaction that is not shared by the researchers themselves.

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