Blinking A Light With Ping

July 6, 2017 by 24 Comments

The Flashing Light Prize is on right now, and that means all our favorite geeks and YouTubers are aspiring to what could be done with a 555. The rules are simple: turn a light bulb on and off somehow. [Sprite_tm] is answering the call, and he’s blinking lightbulbs at the speed of light.

[Sprite]’s method of blinking a light is simple: Use an ESP32 development board to turn on a relay. At the same time, send a packet out to the Internet and through four servers spread across the globe. When the packet goes through servers in Shanghai, the Netherlands, to Hong Kong, to Germany, and finally Japan — and back again — the light bulb turns off. It’s a physical demonstration of the speed of light and the quality of undersea optical fibers.

This route is quite long, and a reasonable estimate for the one-way, great circle path from Shanghai to the Netherlands to Hong Kong to Berlin and finally to somewhere near Osaka is about 36,000 km. A round trip for this light bulb packet is 72,000 km, or about 0.2 light-seconds. There are delays, of course, from fiber and cables not going directly over the Himalayas, delays in routers, and the difference between the speed of light in a vacuum and the speed of light in glass fiber. Still, light is quick, and the light blinks at about 1Hz.

You can check out [Sprite]’s entry video for the Flashing Light Prize below.

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Wearable Breadboard

July 6, 2017 by 12 Comments

We all know what a short circuit is, but [Clement Zheng] and [Manasvi Lalwani] want to introduce you to the shirt circuit. Their goal is to help children, teachers and parents explore and learn electronics. The vehicle is a shirt with a breadboard-like pattern of conductors attaching snaps. Circuit elements reside in stiff felt boxes with matching snaps. You can see it all in action in the video below.

We imagine you could cut the felt pieces out by hand with the included patterns. However, they used a laser cutter to produce the “breadboard” and the component containers. Conductive thread is a must, of course, as are some other craft supplies like glue and regular thread.

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ESP To Wireshark

July 6, 2017 by 13 Comments

Everyone’s favorite packet sniffing tool, Wireshark, has been around for almost two decades now. It’s one of the most popular network analysis tools available, partially due to it being free and open source. Its popularity guaranteed that it would eventually be paired with the ESP32/8266, the rising star of the wireless hardware world, and [spacehuhn] has finally brought these two tools together to sniff WiFi packets.

The library that [spacehuhn] created uses the ESP chip to save Pcap files (the default Wireshark filetype) onto an SD card or send the data over a serial connection. The program runs once every 30 seconds, creating a new Pcap file each time. There are many example scripts for the various hardware you might be using, and since this is written for the ESP platform it’s also Arduino compatible. [spacehuhn] has written this as a proof-of-concept, so there are some rough edges still, but this looks very promising as a network analysis tool.

[spacehuhn] is no stranger to wireless networks, either. His YouTube channel is full of interesting videos of him exploring various exploits and testing other pieces of hardware. He’s also been featured here before for using an ESP8266 as a WiFi jammer.

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Hackaday Prize Entry: Octo, The Robotic Walker

July 6, 2017 by 6 Comments

Walkers like the Strandbeest are favorites due in part to their smooth design and fluid motion, but [Leandro] is going a slightly different way with Octo, an octopodal platform for exploring rough terrain. Octo is based on the Klann linkage which was developed in 1994 and intended to act as an alternative to wheels because of its ability to deal with rough terrain. [Leandro] made a small proof of concept out of soldered brass and liked the results. The next version will be larger, made out of aluminum and steel, and capable of carrying a payload.

The Strandbeest and Octo have a lot in common but differ in a few significant ways. Jansen’s linkage (which the Strandbeest uses) uses eight links per leg and requires relatively flat terrain. The Klann linkage used by Octo needs only six links per leg, and has the ability to deal with rougher ground.

[Leandro] didn’t just cut some parts out from a file found online; the brass proof of concept was drawn up based on an animation of a Klann linkage. For the next version, [Leandro] used a simulator to determine an optimal linkage design, aiming for one with a gait that wasn’t too flat, and maximized vertical rise of the leg to aid in clearing obstacles.

We’ve seen the Klann linkage before in a LEGO Spider-bot. We’re delighted to see [Leandro]’s Octo in the ring for the Wheels, wings, and walkers category of The Hackaday Prize.

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LCaaS – Lawn Care As A Service?

July 6, 2017 by 71 Comments

As often happens while engaged in a mundane task, my mind wandered while I was mowing my small suburban plot of green this weekend. “Why, in 2017, am I still mowing the lawn?” In a lot of ways we’re living in the future  — we walk around with fantastically powerful computers in our pockets, some of us have semi-autonomous cars, and almost anything can be purchased at the touch of a finger and delivered the next day or sooner. We even have robots that can vacuum the floor, so why not a robot lawnmower?

It turns out we do have robotic lawnmowers, but unfortunately, they kind of suck: Continue reading “LCaaS – Lawn Care As A Service?” →

Two-Bit Astrophotography

July 6, 2017 by 12 Comments

The Game Boy Camera is a 128×112 pixel sensor from 1998 that was probably the first digital camera in many, many homes. There’s not much you can do with it now, besides replicate old Neil Young album covers and attempting and failing to impress anyone born after the year 1995. Nevertheless, screwing around with old digital cameras is cool, so [Alex] strapped one fo these Game Boy Cameras to an old telescope.

For any astrophotography endeavor, the choice of telescope is important. For this little experiment, [Alex] used a 6” Fraunhofer telescope built in 1838 at the Old Observatory of Leiden. The Game Boy with Camera was attached to the scope using a universal cell phone adapter. Apparently the ‘universal’ in this universal cell phone adapter is accurate – the setup was easy and [Alex] quickly got an image of a clocktower on his Game Boy.

Turning to the heavens, [Alex] took a look at the most interesting objects you can see with a 6-inch telescope. Images of the moon turned out rather well, with beautiful 2-bit dithering along the terminator. Jupiter was a bright white spot in a sea of noise, but [Alex] could see four slightly brighter pixels orbiting where Stellarium predicted the Galilean moons would be.

Was this experiment a success? Between cloudy nights and a relatively small telescope, we’re saying yes. These are pretty impressive results for such a terrible digital camera.

Gyrators: The Fifth Element

July 6, 2017 by 32 Comments

A few years ago, there was a stir about a new fundamental component called a memristor. That wasn’t the first time a new component type was theorized though. In 1948 [Bernard Tellegen] postulated the gyrator. While you can’t buy one as a component, you can build one using other components. In fact, they are very necessary for some types of design. Put simply, a gyrator is a two-terminal device that inverts the current-voltage characteristic of an electrical component. Therefore, you can use a gyrator to convert a capacitor into an inductor or vice versa.

Keep in mind, the conversion is simply the electrical properties. Normally, current leads voltage in a capacitor and lags it in an inductor, and that’s what a gyrator changes. If you use a gyrator and a capacitor to make a virtual inductor, that inductor won’t magnetically couple to another inductor, real or simulated. There’s no magnetic field to do so. You also don’t get big voltage spikes caused by back EMF, which depending on your application could be a plus or a minus. But if you need an ungainly inductor in a circuit for its phase response, a gyrator may be just the ticket.

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