Translate Color To Smell With Bouquet

Hope springs eternal for Smell-O-Vision. [Niklas Roy] recently taught a workshop called Communication Devices at ÉCAL in Lausanne, Switzerland. Four of his Media & Interaction Design students built a scanner that detects colors and emits a corresponding scent.

The project consists of an Arduino connected to a color sensor as well as a SparkFun EasyDriver. The EasyDriver controls a stepper motor which rotates a disc of scent swatches so you sniff the swatch corresponding with the color. The students chose strawberry for red, and blue ended up being “ocean”-scented room spray.

With design students involved it’s no surprise the project looked good. Bouquet’s creators [Erika Marthins], [Arthur Moscatelli], [Pietro Alberti] and [Andrea Ramìrez Aburto] gave the device an intriguingly featureless look, and the “olfactory graphic design” posters they created to demonstrate it look great as well.

[Niklas Roy]’s excellent projects have graced the pages of Hackaday many times before. Be sure to check out his RC Beer Crate, his Music Construction Machine, and his Thermal Imaging Rig if you haven’t already.

Continue reading “Translate Color To Smell With Bouquet”

Hacking The Aether: How Data Crosses The Air-Gap

It is incredibly interesting how many parts of a computer system are capable of leaking data in ways that is hard to imagine. Part of securing highly sensitive locations involves securing the computers and networks used in those facilities in order to prevent this. These IT security policies and practices have been evolving and tightening through the years, as malicious actors increasingly target vital infrastructure.

Sometimes, when implementing strong security measures on a vital computer system, a technique called air-gapping is used. Air-gapping is a measure or set of measures to ensure a secure computer is physically isolated from unsecured networks, such as the public Internet or an unsecured local area network. Sometimes it’s just ensuring the computer is off the Internet. But it may mean completely isolating for the computer: removing WiFi cards, cameras, microphones, speakers, CD-ROM drives, USB ports, or whatever can be used to exchange data. In this article I will dive into air-gapped computers, air-gap covert channels, and how attackers might be able to exfiltrate information from such isolated systems.

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Hackaday Prize Entry: Augmented Reality For Firefighters

Augmented reality is all the rage right now, and it’s all because of Pokemon. Of course, this means the entire idea of augmented reality is now wrapped up in taking pictures of Pidgeys in their unnatural setting. There are more useful applications of augmented reality, as [vijayvictory]’s Hackaday Prize entry shows us. He’s built an augmented reality helmet for firefighters that will detect temperature, gasses, smoke and the user’s own vital signs, displaying the readings on a heads up display.

The core of the build is a Particle Photon, a WiFi-enabled microcontroller that also gives this helmet the ability to relay data back to a base station, ostensibly one that’s not on fire. To this, [vijayvictory] has added an accelerometer, gas sensor, and a beautiful OLED display mounted just behind a prism. This display overlays the relevant data to the firefighter without obstructing their field of vision.

Right now, this system is fairly basic, but [vijayvictory] has a few more tricks up his sleeve. By expanding this system to include a FLIR thermal imaging sensor, this augmented reality helmet will have the ability to see through smoke. By integrating this system into an existing network and adding a few cool WiFi tricks, this system will be able to located a downed firefighter using signal trilateralization. It’s a very cool device, and one that should be very useful, making it a great entry for The Hackaday Prize.

Make Your Own Infrared Camera On The Cheap!

This is a super fun hack that’s been around for ages — but now with cheap full 1080P HD camera availability, it’s probably a good time to make your own infrared camera!

It’s actually a very easy modification to perform. All cameras are capable of “seeing” infrared light, but for standard photography and video, you don’t want to see the infrared light. So most sensors just have an infrared filter in front of the sensor, to block out any excess infrared light. If you remove it … you have a converted infrared camera.

The following video shows exactly how to modify a camera to do this. It is a bit misleading though as it labels it as a thermal camera; and while it is seeing “infrared”, it’s not actually full thermal infrared, like a FLIR or Seek Thermal can see — it’s a mixture of visible and near infrared light. You will be able to see some hot things glowing through the camera, but not to the same degree as a real thermal imaging device. Continue reading “Make Your Own Infrared Camera On The Cheap!”

Infrared Detector Selects Over A Wide Range

You can classify infrared light into three broad ranges: short wave, medium wave, and long wave. Traditionally, sensors concentrate on one or two bands, and each band has its own purpose. Short wave IR, for example, produces images similar to visible light images. Long wave is good for thermal imaging.

Researchers have announced a new detector that, by adjusting a bias, can detect all three bands using a simple approach that stacks different absorption layers over a semiconductor substrate. The device only requires two terminals and is very efficient, although the efficiency varies based on the band.

We’ve covered infrared sensing before. We’ve even seen DSLRs hacked into IR sensors. This new research might be a bit much to duplicate in your garage. After all, it requires tellurium doped gallium antimonide substrates and sophisticated processing equipment. However, this research will probably lead to practical devices that will find their way into projects before too long.

A Ridiculous Way To Light An LED: Candle-power

If you have ever entertained yourself by reading comprehensive electronic-theory textbooks you’ll have seen references to technologies that sound really interesting but which you will rarely hold in your hand. They may be dead-ends that have been superseded by more recent innovations, or they may be technologies that have found uses but in other fields from those in which they originally showed promise. What if you could take these crazy parts and actually build something?

[Fedetft] has an interesting project that combines two of those intriguing textbook references, he’s created a thermopile that lights an LED through an inverter whose oscillator is a tunnel diode. Dig out the textbook.

If you’ve used a thermocouple thermometer or a semiconductor thermoelectric generator then you’ll have encountered the thermoelectric effect. Perhaps you’ve even operated a Peltier cooling element in this mode. When a circuit is made with two junctions between different types of conductor with a temperature difference between the two junctions, a current will flow in the circuit which is dependent on both the scale of the temperature difference and the properties of the conductors.

A thermopile is a collection of these thermoelectric junction circuits between metal conductors, arranged in series to increase the voltage. [Fedetft]’s thermopile uses chromel and alumel wires taken from a K-type thermocouple. He’s made six sets of junctions, and supported them with small pieces of mica sheet. Using the heat from a candle he found he could generate about 200mV with it, at about 3.7mW.

The RCA tunnel diode inverter circuit
The RCA tunnel diode inverter circuit

Such a tiny source of electricity would be of little use to light an LED directly, so he needed to build an inverter. And that’s where the tunnel diode comes in. Tunnel diodes have a negative-resistance region that can be used to amplify and oscillate at extremely high frequencies in extremely simple circuits, yet they’re not exactly a device you’d encounter very often in 2016. [Fedetft] has a Russian tunnel diode, and he’s used it with a toroidal transformer in an inverter circuit he found in an RCA tunnel diode manual from 1963. It’s a two-component Joule Thief. The RCA manual is a good read in itself for those curious about tunnel diodes.

The resulting circuit produces a 15kHz oscillation with 4.5v peaks, and has just enough power to light an LED.

While it might seem pointless to barely light an LED from a brightly lit candle, the important part of [Fedetft]’s project is to gain some understanding of two of those technological backwaters from the textbooks. And we applaud that.

It’s the mark of a truly esoteric technology that it features rarely on Hackaday, and neither of these two disappoint. We’ve only mentioned tunnel diode in passing when looking at diodes in general, and we’ve tended to use “thermopile” in another sense to refer to thermal imaging cameras.

New Part Day: STM32F7, An ARM Cortex-M7

It was announced last year, but ST is finally rolling out the STM32F7, the first microcontroller in production that is based on the ARM Cortex-M7.

The previous go-to part from the ST catalog was the STM32F4, an extremely powerful chip based on the ARM Cortex M4 processor. This chip was incredibly powerful in its time, and is still a respectable choice for any application that needs a lot of horsepower, but not a complete Linux system. We’ve seen the ~F4 chip pump out 800×600 VGA, drive a thermal imaging camera, and put OpenCV inside a webcam. Now there’s a new, even more powerful part on the market, and the mind reels thinking what might be possible.

Right now there a few STM32F7 parts out, both with speeds up to 216MHz, Flash between 512k and 1MB, and 320kB of RAM. Peripherals include Ethernet, USB OTG, SPDIF support, and I²S. The most advanced chip in the line includes a TFT LCD controller, and a crypto processor on-chip. All of the chips in the STM32F7 line are pin compatible with the STM32F4 line, with BGA and QFP packages available.

As with the introduction of all of ST’s microcontrollers, they’re rolling out a new Discovery board with this launch. It features Ethernet, a bunch of audio peripherals, USB OTG, apparently an Arduino-style pin layout, and a 4.3 inch, 480×272 pixel LCD with capacitive touch. When this is available through the normal distributors, it will sell for around $50. The chips themselves are already available from some of the usual distributors, for $17 to $20 in quantity one. That’s a chunk of change for a microcontroller, but the possibilities for what this can do are really only limited by an engineer’s imagination.