Counting Is For Sheep: Use A Light To Fall Asleep

January 26, 2018 by Kristina Panos 12 Comments

How do you get to sleep at night? For some of us, it can be the most difficult thing we do all day. Worrying about falling asleep and letting other intrusive thoughts in night after night only compounds the problem, as less sleep leads to depression which (for us) leads to even less sleep. We lay there, trapped inside a vortex of churning thoughts, imprisoned in a mind that feels like it’s malfunctioning and half-wishing for a future where instructor-led meditation videos can be beamed to the insides of our eyelids. In the meantime, there is FADing, the Fall Asleep Device.

FADing takes its cues from a relaxation technique that uses light to focus your attention and control your breathing. The light’s intensity waxes and wanes on a schedule designed to get you down from the average eleven breaths per minute to a zen-like six breaths per minute. You surrender to the light, breathing in as it intensifies and breathing out as it fades. There are commercial products that bring this technique to the bedroom, but they aren’t cheap and don’t offer much control. Fail to fall asleep in the prescribed window and you’re back to square one with one more thing to think about: buyer’s remorse.

[Youz] was inspired by these devices but dissatisfied with the price tag and lack of options, so he created his own version with a flexible window of operation that appeals to both back- and side-sleepers. It uses an Arduino Nano and two momentaries to control two LEDs, a relay to hold the power after startup, a 9V, and a diode to protect the Nano. One LED projects on the ceiling, and the other radiates through a slice of acrylic which has been shaded blue. One button is for power, and the other lets you add time by two-minute increments. You can see the build video after the break and then tell us how you’d do it with a 555, a coin cell, and a chunk of uranium glass in the comments.

Once you can focus on your breathing without a light, reuse that Nano to measure the quality of all that sleep you’re getting.

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A Motion Sensing Light For Your Entrance Hallway

November 11, 2017 by James Hobson 25 Comments

Arriving home to a dark house with an armful of anything is usually an exercise in fumbling confusion until someone manages to turn on a light. [Pavel Gesyuk] has circumvented this problem entirely by building and installing a motion detecting entrance light!

[Gesyuk] is using an Arduino clone by the name of Funduino Mini Pro, a 2-channel, 2-way relay, — he only needed one, but you use what you have on hand — a recycled power supply to convert 220V AC to 5V DC, and an infrared sensor.

The project’s goal — in excess of a lighting solution for an entrance hallway — was the learn the ins and outs of the Arduino and motion sensors. After some initial hurdles familiarizing himself with the Arduino, [Gesyuk] wired everything together on a protoboard and stuck it in a plastic case — loose wires in a high traffic area doesn’t a safe home make.

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Evil Hotspot Costume Makes Valuable Connections

November 6, 2017 by Kristina Panos 14 Comments

This year for Hallowe’en, [Scott] went out dressed as a Comcast xfinity hotspot. Funny, yes, but there’s a deeper meaning here. [Scott] really went as a walking PSA that illustrates the dangers of making assumptions about the relative safety of WiFi networks based solely on their broadcast names.

[Scott] could have gone chaotic evil with this setup, but he didn’t. No one could actually get on the Internet through him. Inside the “hotspot” are a Wi-Fi adapter and a Pi Zero running a captive portal. It broadcasts the default ‘XFINITY’ and ‘xfinitywifi’ SSIDs, plus a bunch of other common network names. Whenever anyone tries to connect, or worse, their phone automatically connects, they’ll hear a sad tuba cadence. This comes courtesy of a multi-sound effects box that’s controlled by the Pi through a relay board.

Meanwhile, the mark’s device is redirected to an internally-hosted “xfinity” login page. Anyone who actually goes on to enter their login credentials is treated to a classic horror film scream sample while the evil hotspot quietly stores their name and password and displays them on an e-ink display for all to see — a walking e-ink wall of sheep. Check out the demo after the break.

[Scott]’s evil hotspot is powered by a huge battery that can run it for 24 hours. Here’s a wind- and solar-powered WAP we covered several years ago.

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Hackaday Prize Entry: Pyrotechnics Sequencer With Wireless Control

October 19, 2017 by John Baichtal 26 Comments

[visualkev]’s friend was putting on his own fireworks show by lighting each one in turn, then running away. It occurred to [visualkev] that his friend wasn’t really enjoying the show himself because he was ducking for cover instead of watching the fun. Plus, it was kind of dangerous. Accordingly, he applied his hacker skills to the challenge by creating a custom fireworks sequencer.

He used a custom PCB from OSH Park with an ATMega328P controlling eight TPIC6C595 8-bit shift registers, which in turn trip the 64 relays connecting to the fireworks. A 5V regulator supplies the project from 5 5AA batteries, and he kept the wires neat with 8-wire ribbon cables.

Starting the sequence is a generic wireless remote — a cheapie from Walmart — allowing [visualkev]’s friend can launch the fireworks with one hand while working the barbecue tongs with the other.

The Bane Of Aftermarket Car Alarms

October 10, 2017 by Lewin Day 79 Comments

The humble car alarm has been around almost as long as the car itself, first being developed by an unknown prisoner in Denver, circa 1913. To the security-conscious motorist, they make a lot of sense. The noise of a car alarm draws attention which is the last thing a would-be thief wants, and the in-built immobilizers generally stop the car being moved at all without a time-consuming workaround. Both are a great deterrent to theft.

It may then surprise you to know that I, dear readers, consider the aftermarket car alarm to be one of the most heinous devices ever fitted to the modern automobile. Combining the unholy trifecta of being poorly designed, cheaply made, and fitted by only the most untalented or uncaring people to wield a soldering iron, they are a blight that I myself refuse to accept.

It was my very own Mazda that suffered at the hands of a car alarm system. Two days after purchasing the car, the keyfob died, and thus the car would no longer start. My other car was already out of action due to bent valves, and I needed to get to work, so I figured as a competent hacker, I’d be able to quickly disable it.

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An Introduction To Solid State Relays

September 26, 2017 by Sean Boyce 54 Comments

When we think of relays, we tend to think of those big mechanical things that make a satisfying ‘click’ when activated. As nice as they are for relay-based computers, there are times when you don’t want to deal with noise or the unreliability of moving parts. This is where solid-state relays (SSRs) are worth considering. They switch faster, silently, without bouncing or arcing, last longer, and don’t contain a big inductor.

An SSR consists of two or three standard components packed into a module (you can even build one yourself). The first component is an optocoupler which isolates your control circuit from the mains power that you are controlling. Second, a triac, silicon controlled rectifier, or MOSFET that switches the mains power using the output from the optocoupler. Finally, there is usually (but not always) a ‘zero-crossing detection circuit’. This causes the relay to wait until the current it is controlling reaches zero before shutting off. Most SSRs will similarly wait until the mains voltage crosses zero volts before switching on.

If a mechanical relay turns on or off near the peak voltage when supplying AC, there is a sudden drop or rise in current. If you have an inductive load such as an electric motor, this can cause a large transient voltage spike when you turn off the relay, as the magnetic field surrounding the inductive load collapses. Switching a relay during a peak in the mains voltage also causes an electric arc between the relay terminals, wearing them down and contributing to the mechanical failure of the relay.

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Knitting ALUs (and Flipdots)

September 20, 2017 by Elliot Williams 6 Comments

[Irene Posch] is big into ~~knitted~~ fabric circuits. And while most of the textile circuits that we’ve seen are content with simply conducting enough juice to light an LED, [Irene]’s sights are set on ~~knittable~~ crafted arithmetic logic units (ALUs). While we usually think of transistors as the fundamental building-blocks of logic circuits, [Irene] has developed what is essentially a ~~knit~~ crochet relay. Be sure to watch the video after the break to see it in construction and in action.

The basic construction is a coil of conductive thread that forms an electromagnet, and a magnetic bead suspended on an axle so that it can turn in response to the field. To create a relay, a flap of knit conductive thread is attached to the bead, which serves as the pole for what’s essentially a fabric-based SPDT switch. If you’ve been following any of our relay-logic posts, you’ll know that once you’ve got a relay, the next step to a functioning computer is a lot of repetition.

How does [Irene] plan to display the results of a computation? On knit-and-bead flipdot displays, naturally. Combining the same electromagnet and bead arrangement with beads that are painted white on one side and black on the other yields a human-readable one-bit display. We have an unnatural affinity for flipdot displays, and making the whole thing out of fabric-store components definitely flips our bits.

Anyway, [Irene Posch] is a textile-tech artist who you should definitely be following if you have any interest in knittable computers. Have you seen anything else like this? Thanks [Melissa] for the awesome tip!

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