Tag Archives: wifi

Sir, It Appears We’ve Been Jammed!

via hardware – Hackaday

In a move that would induce ire in Lord Helmet, [Kedar Nimbalkar] has hacked together a simple — yet effective — WiFi jammer that comes with a handful of features certain to frustrate whomever has provoked its wrath.

The jammer is an ESP8266 development board — running some additional custom code — accessed and controlled by a cell phone. From the interface, [Nimbalkar] is able to target a WiFi network and boot all the devices off the network by de-authenticating them. Another method is to flood the airspace with bogus SSIDs to make connecting to a valid network a drawn-out affair.

This kind of signal interruption is almost certainly illegal where you live. It does no permanent damage, but once again raises the existing deauth exploit and SSID loophole. [Nimbalkar]’s purpose in building this was for educational purposes and to highlight weaknesses in 802.11 WiFi protocols. The 802.11w standard should alleviate some of our fake deauth woes by using protected frames. Once the device authenticates on a network it will be able to detect fake deauth packets.

We featured a more targeted version of this hack that can be done using a PC — even targeting itself! And more recently there was a version that can target specific devices by jumping on the ACK.

[Thanks for the tip, Itay!]


Filed under: hardware, wireless hacks

WiFi Power Bar!

via hardware – Hackaday

Ever wanted to access a file or run some program on your computer while away from home, but the darned thing is turned off? Finding themselves occasionally working away from home and not wanting to leave their computer on for extended periods, [robotmaker]’s solution was to hack into existence a WiFi-controlled power bar!

esp8266-powerbar-thumbInside the junction box, an eight-channel relay is connected to an ESP8266 module. The module uses MQTT to communicate with Home Assistant and is powered by a partially dismembered USB AC adapter — wrapped in kapon tape for safe-keeping. The entire bar is wired through a 10A fuse, while also using a fire resistant 4-gang electrical box. Once the outlets were wired in, closing it up finished up the power bar.

[robotmaker] controls the outlets via a cheap smartphone — running HADashboard — mounted to a wall with a 3D printed support. Don’t worry — they’ve set up the system to wait for the PCs to power down before cutting power, and the are also configured to boot up when the relay turns on.

The best part — the power bar only cost $25.

[via /r/homeautomation]


Filed under: hardware, home hacks, wireless hacks

A Smart Wand for all us Muggles

via hardware – Hackaday

Arthur C. Clarke said that “any sufficiently advanced technology is indistinguishable from magic.” Even though we know that something isn’t “magic”, it’s nice to see how close we can get. [Dofl] and his friends, big fans of the magic in Harry Potter, thought the same thing, and decided to create a magic wand that they could use themselves.

muggle-wand-internalsThe wand itself is 3D printed and has a microcontroller and WiFi board, a voice recognition board, a microphone, and a vibrating motor stuffed inside. The wand converts the voice into commands and since the wand is connected to WiFi, the commands can be used to communicate with your WiFi connected lights (or your WiFi connected anything, really.) Five voice commands are recognized to turn on and off music, the lights, and a “summon” command which is used in the video to request a hamburger from delivery.com. For feedback, the motor is vibrated when a command is recognized.

There’s not much technical information in the original article, but I’m sure our readers could figure out the boards used and could suggest some alternatives to get the wand’s form factor down a bit.  Over the years, other wands have appeared on our pages, using some different technologies.  It’s a fun way to interact with the environment around you, even if you know the “magic” involved is just boring old technology.


Filed under: hardware

Make a WiFi-controlled mini robot using the new MKR2UNO

via Arduino Blog

MKRRobotTutorial

A few days ago, we launched the MKR2UNO Adapter, which enables you to easily turn an Arduino Uno form factor project into a MKR1000-based one. Simply mount your IoT board to the adapter, plug in any Uno shield and have a wireless device in no time.

Our newly-published tutorial provides a step-by-step overview of how to build a WiFi-controllable robot using the MKR2UNO Adapter with a MKR1000 and an Arduino Motor Shield.

MKR2Uno

This project combines the Arduino MKR1000’s web server and Arduino Motor Shield’s capabilities to drive a pair of different DC motors. A basic interface is hosted and hard-coded in the MKR1000, allowing the user to maneuver the robot up, down, left or right.

Check out all of the schematics and code here!

oCat is a real-time tracker for popular cat videos

via Arduino Blog

ocat

Over the last couple of years, cat videos have become the undisputed champions of the web. Whether it’s kittens playing with their shadows to failed jump attempts to giving each another massages, we’re all guilty of watching a few of these clips from time to time (yes, even at work). Built with this in mind, oCat is a real-time tracker for feline-related activity on the Internet.

oCat consists of two parts: the oCat News Distractor and the Kitty o’Cat Twitter bot. Using Google’s YouTube API, the system works by continuously monitoring for new uploads, the number of new views each day, or a specific video that has received a remarkable amount of attention. It then tweets these stats and prints them out on thermal paper, stamping a paw print on the timeline for every 1,000 views.

Created by Annika Engelhardt, a digital media design master’s student at the University of the Arts in Bremen, oCat uses an Arduino along with an ESP Wi-Fi module, a servo, and an LCD screen. The aim of the project is to increase and reveal the amount of hours people spend watching cat videos online.

The cat is an altered Maneki-neko, holding a stamp using welding wire and hot glue. Even though I filled the stamp with extra ink, it did not work properly and I had to cut out the paw-shape from a sponge and glue it onto the original stamp.

The thermal printer used in the device needs a USB connection, so I used a Raspberry Pi to control it. I wrote a Python script that checks four different RSS news feeds for new posts every 15 minutes and prints one headline with a timestamp every minute.

The Twitter bot was programmed using Python and a library called tweepy. Most of the script is reading JSON files, juggling and comparing data and text files and in the end mixing up parts of a sentence to form a tweet. The bot will be enhanced in the future

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Engelhardt exhibited the project at Galerie Flut in Bremen back in October. You can find more pictures and information on the project here.

App note: Using Vishay infrared receivers in a Wi-Fi environment

via Dangerous Prototypes

an_vishay_usinginfraredreceiversinwifi

2.4Ghz and 5 Ghz Wi-fi signals can sometimes affect IR receivers, here’s Vishay’s app note about them. Link here (PDF)

In recent years, Wi-Fi connectivity has penetrated most consumer electronic devices used for media reproduction. New TVs, satellite receiver and cable boxes, and streaming devices are more often than not built with Wi-Fi capabilities at multiple frequencies: 2.4 GHz and 5 GHz. Most of these appliances continue to support an infrared (IR)-based remote control link, often even when the device also supports a newer RF-based remote control.
IR remote control receivers are built with highly sensitive wideband input stages and are able to detect signals near the noise level of their circuitry. In noisy environments, such as with both low- and high-frequency electromagnetic interference (EMI), the receiver may be noise-triggered, typically manifesting itself in the form of spurious pulses at its output. Most Vishay IR receiver packages are designed with metal shields to effectively guard the receiver against low-frequency EMI. However, these metal shields have not proven entirely satisfactory against high-frequency EMI in the GHz range used for Wi-Fi.