Hacklet 97 – Camera Projects

February 26, 2016 by Adam Fabio 9 Comments

We last covered camera projects way back in Hacklet #11. A ton of camera projects have been added to Hackaday.io since then. While the rest of the world is taking selfies, hackers, makers, and engineers have been coming up with new ways to hack their image capture devices. This week on the Hacklet, we’re taking a look at some of the best camera projects on Hackaday.io!

First up is [aleksey.grishchenko] with PiXel camera. PiXel is a camera and a live video display all in one, We wouldn’t exactly call it high-definition though! A Raspberry Pi uses its camera module to capture images of the world. [Aleksey] then processes those images and displays them on a 32 x 32 RGB LED matrix. This matrix is the same kind of tile used in large outdoor LED signs. The result is a surreal low resolution view of the world. Since the Pi, batteries, and camera all hide behind the LED matrix, there is an unobstructed view of the world around you. [Aleksey] used [Henner Zeller’s] matrix library to make this hack happen.

Next up is [Esben Rossel] with Linear CCD module. [Esben] is building a Raman spectrometer, much like 2014 Hackaday Prize finalist [fl@C@] with his own ramanPi. The heart of a spectrometer is the linear image capture device. Both of these projects use the same TCD1304 linear CCD. Linear Charge Coupled Devices (CCDs) are the same type of device used in flatbed document scanners. The output of the CCD is analog, so an ADC must be used to capture the data. [Esben] is using an STM32F401RE on a Nucleo board as the control logic. The ST’s internal ADC converts the analog signal to digital. From there, it’s time to process all the spectra.

[Chiprobot] brings the classic Wii remote camera to the internet of things with
ESP8266 meets Wii Mote Camera. The Wii remote uses a camera which doesn’t output images, instead it plots the location of up to four IR LEDs. Normally these LEDs are located in the poorly named sensor bar that is sold with the Wii. Hackers have been using these cameras in projects for years now. [Chiprobot] paired his camera with the modern classic ESP8266 WiFi module. The ‘8266 is programmed to read data from the camera’s I2C bus. It then sends the data as an SVG request to the W3C website. W3C returns a formatted image based on those coordinates. The resulting image is a picture of the IR LEDs seen by the camera. Kind of like sending your negatives out to be developed.

Finally, we have [GuyisIT] with Raspberry Pi Photobooth. Photo booths are all the rage these days. First it was weddings, but now it seems like every kids party has one. [GuyisIT] didn’t rent a booth for his daughter’s birthday, he built one using his Raspberry Pi and Pi camera. The project is written in python, based upon [John Croucher’s] code. When the kids press a button, the Pi Snaps a series of pictures. The tiny Linux computer then joins and rotates the images while adding in some superhero themed graphics. Finally the Pi prints the image on to a photo printer. The biggest problem with this hack is re-triggering. The kids loved it so much, they kept pressing the big red button!

If you want to see more camera projects, check out our updated camera projects list! If I missed your project, don’t be shy! Just drop me a message on Hackaday.io. That’s it for this week’s Hacklet. As always, see you next week. Same hack time, same hack channel, bringing you the best of Hackaday.io!

FCC Locks Down Router Firmware

February 26, 2016 by Brian Benchoff 112 Comments

For years, we have been graced with consumer electronics that run some form of Linux, have a serial port on the circuit board somewhere, and are able to be upgraded through official and unofficial means. That digital picture frame you got for Christmas in 2007 and forgot to regift in 2008? That’s a computer, and it would make a wonderful Twitter feed display. Your old Linksys WRT54G router? You can make a robotic lawnmower out of that thing. The ability to modify the firmware of consumer electronics is the cornerstone of Hackaday’s editorial prerogative. Now that right we have all enjoyed is in jeopardy, thanks to regulations from the FCC and laziness from router manufacturers.
Continue reading “FCC Locks Down Router Firmware” →

The New Heathkit Strikes Again

February 26, 2016 by Dan Maloney 57 Comments

Alright, this is getting embarrassing.

The rebooted Heathkit has added another kit to its offerings. This time it’s an inexplicably simple and exorbitantly priced antenna for the 2-meter band. It joins their equally bizarre and pricey AM radio kit in the new product lineup, and frankly we’re just baffled by the whole affair.

About the most charitable thing you can say about their “Pipetenna” is that it’ll probably work really well. Heathkit throws some impedance and SWR charts on the website, and the numbers look pretty good. Although Heathkit doesn’t divulge the design within the “waterproof – yes, waterproof!” housing, at 6 dBi gain and only five feet long, we’re going to guess this is basically a Slim Jim antenna stuffed in a housing made of Schedule 40 PVC tubing. About the only “high-end” component we can see is the N-type coax connector, but that just means most hams will need and adapter for their more standard PL-259 terminated coax.

Regardless of design, it’s hard to imagine how Heathkit could stuff enough technology into this antenna to justify the $149 price. Hams have been building antennas like these forever from bits and pieces of wire lying around. Even if you bought all new components, including the PVC pipe and fittings, you’d be hard pressed to put $50 into a homebrew version that’ll likely perform just as well.

The icing on this questionable cake, though, is the sales copy on the web page. The “wall of text” formatting, the overuse of superlatives, and the cutesy asides and quips remind us of the old DAK Industries ads that hawked cheap import electronics as the latest and greatest must-have device. There’s just something unseemly going on here, and it doesn’t befit a brand with the reputation of Heathkit.

When we reviewed Heathkit’s AM radio kit launch back in December, we questioned where the company would go next. It looks like we might have an answer now, and it appears to be “nowhere good.”

Adding Spice To Your Workbench

February 26, 2016 by Al Williams 43 Comments

Most of us didn’t fight in World War II, drive a race car, or fly the Space Shuttle. But with simulation, you can experience at least some of what it would be like to do those things. Granted, playing Call of Duty isn’t really the same as going to war. No matter what you are simulating, it only goes so far. However, you can get a lot of value from a simulation. I’d bet the average kid who has played Call of Duty knows more about WWII locales and weapons than my high school history teacher.

When it comes to electronics, simulation is an excellent way to get insight into a circuit’s operation. After all, most circuits operate in the abstract–you can’t look at an audio amplifier and see how it works without a tool like a scope. So simulation, when done well, can be very satisfying. You just have to be careful to remember that it isn’t always as good as the real thing.

That’s Spicy

One of the best-known electronics simulators is Spice, which Berkeley created in 1973. In its original form, you had to punch cards that described your circuit and the analysis you wanted to perform. Modern PC versions sometimes replace the deck of cards with a text file. The best modern versions, though, give you a GUI that allows you to draw a schematic and then probe it to see the results.

There are several paid and free versions of Spice (and other simulators) that include a GUI. One of the best for a casual user is the free offering from Linear Technology called LTSpice.

Linear makes LTSpice available and populates it with models for their devices in the hopes you’ll buy components from them. However, the software is entirely usable for anything, and it has a powerful set of features. Linear produces the software for Windows, but I can attest that it runs just fine under Wine on Linux. The Web site will invite you to register, but you don’t have to if you don’t want to.

Continue reading “Adding Spice To Your Workbench” →

Passive WiFi On Microwatts

February 26, 2016 by Elliot Williams 30 Comments

A lot of you use WiFi for your Internet of Things devices, but that pretty much rules out a battery-powered deployment because WiFi devices use a lot of juice. Until now. Researchers at the University of Washington have developed a passive WiFi implementation that uses only microwatts per device.

Working essentially like backscatter RFID tags do, each node has a WiFi antenna that can be switched to either reflect or absorb 2.4 GHz radiation. Your cell phone, or any other WiFi device, responds to this backscattered signal. All that’s missing is a nice steady signal to reflect.

A single, plugged-in unit provides this carrier wave for multiple WiFi sensor nodes. And here’s the very clever part of the research: to keep the carrier from overwhelming the tiny modulated signal that’s coming from the devices, the plugged-in unit transmits off the desired frequency and the battery-powered units modulate that at just the right difference frequency so that the resulting (mixed) frequency is in the desired WiFi band.

If you’re a radio freak, you’ll recognize the WiFi node’s action being just like a frequency mixer. That’s what the researchers (slightly mysteriously) refer to as the splitting of the analog transmission stage from the digital. The plugged-in unit transmits the carrier, and the low-power nodes do the mixing. It’s like a traditional radio transmitter, but distributed. Very cool.

There’s a bunch more details to making this system work with consumer WiFi, as you’d imagine. The powered stations are responsible for insuring that there’s no collision, for instance. All of these details are very nicely explained in this paper (PDF). If you’re interested in doing something similar, you absolutely need to give it a read. This idea will surely work at lower frequencies, and we’re trying to think of a reason to use this distributed transmitter idea for our own purposes.

And in case you think that all of this RFID stuff is “not a hack”, we’ll remind you that (near-field) RFID tags have been made with just an ATtiny or with discrete logic chips. The remotely-powered backscatter idea expands the universe of applications.

Thanks [Ivan] for the tip!

Continue reading “Passive WiFi On Microwatts” →

Samsung ARTIK Dev Boards Start To Ship

February 26, 2016 by Jenny List 23 Comments

Another week’s news, another single board computer aimed at Internet of Things applications is launched. This time it’s Samsung’s Artik 5, a platform they’ve been talking about for a while now but which you can now buy as a dev board from Digi-Key for $99.99. For that you get Wi-Fi, Bluetooth and Zigbee connectivity, a dual-core ARM Cortex A7 running at 1GHz, 512MB of memory, and 4GB of eMMC storage. There are the usual plethora of interfaces: GPIO, I2C, SPI, UART, SDIO, USB 2.0, JTAG, and analogue.

The single board computer marketplace is starting to look rather crowded, and with so many competitors to choose from at more reasonable prices you might ask yourself why the ARTIK could be of interest to a maker. And given that Samsung are positioning it in their literature on its increased security for use in commercial applications such as IoT hubs, IP cameras and industrial and commercial lighting systems, you’d probably be on to something. If you were to make a very rough analogy with the Raspberry Pi range this has more in common with the Compute Module when it comes to intended marketplace than it does with the Pi Zero.

One answer to that question though could be that it is one of the first devices to support the Thread networking protocol for IoT devices. Thread is a collaboration between Google and a range of other interested parties that has been designed to deliver reliable and secure mesh networking for IoT devices in connected homes. As with all new connectivity protocols only time will tell whether Thread is the Next Big Thing, but it is interesting to note in this board nevertheless.

The ARTIK hasn’t made many waves as yet, though we covered the story when it was announced last year. It is worth mentioning that the ARTIK 5 is only the first of three platforms, the ARTIK 1 will be a tiny board with Bluetooth LE aimed at portable and wearable applications while the ARTIK 10 will be an octo-core powerhouse aimed at mulitmedia processing and network storage applications.

Variable Stiffness Joints For Robots And More

February 25, 2016 by Al Williams 10 Comments

The human body has many miraculous capabilities that we often take for granted. One of the more subtle ones is the variable stiffness of your joints. In technical terms, stiffness refers to the ability to resist a load. Delicately manipulating an artist’s paint brush, for example, doesn’t require much load resistance, but does require fine control. However, that same artist might pick up a bowling ball with a stiffer joint (and, usually, less fine control).

[Christopher Churchill] and some colleagues have a novel mechanical device that can rapidly change stiffness. The device could have applications in robotics and other devices. It can also transmit or attenuate vibration since non-stiff joints don’t pass vibrations as easily as stiff ones.

Continue reading “Variable Stiffness Joints For Robots And More” →