Ion Powered Airplane: Not Coming To An Airport Near You

December 31, 2018 by 23 Comments

Not that we don’t love Star Trek, but the writers could never decide if ion propulsion was super high tech (Spock’s Brain) or something they used every day (The Menagerie). Regardless, ion propulsion is real and we have it today on more than one spacecraft. However, MIT recently demonstrated an ion-powered airplane. How exciting! An airplane with no moving parts that runs on electricity. Air travel will change forever, right? According to [Real Engineering], ion-propelled (full-sized) aircraft run into problems with the laws of physics. You can see the video explaining that, below.

To understand why, you need to know two things: how ion drive works and how the engines differ when using them in an atmosphere. Let’s start with a space-based ion engine, a topic we’ve covered before. Atoms are turned into ions which are accelerated electrically. So the ion engine is just using electricity to create thrust exhaust instead of burning rocket fuel.

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Take A Mini Lathe For A Spin

December 31, 2018 by 24 Comments

[This Old Tony] is no stranger to quality tools, but he started on a mini lathe. Nostalgia does not stop him from broadcasting his usual brand of snark (actually, it is doubtful that anything short of YouTube going offline will stop that). He rates the lathe’s ability to machine different materials and lets you decide if this is an investment, or a money pit.

Lathe parts range from a chintzy start/stop button assembly that looks like it would be at home on a Power Wheels restoration project to a convenient cam locking mechanism on the tail stock which is an improvement on the lathe with which our narrator learned. We see the speed tested and promptly disproved as marketing hoopla unless you allow for a 40% margin of error. It uses a 500 watt DC motor, so don’t try correcting for mains power frequency differences. The verdict on the lead screw and thread dial is that you get what you pay for and this is demonstrated by painstakingly cutting threads into aluminum. Finally, we see torture tests on cold rolled steel.

Maybe someone from the mini lathe community will stop by with their two-cents. If you appreciate this introduction to lathes, consider [This Old Tony]’s guide to CNC machines or injection molding. But for us, [Quinn Dunki’s] series of machine tools has been a real treat this year.

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35C3: Finding Bugs In Bluetooth

December 30, 2018 by 24 Comments

[Jiska Classen] and [Dennis Mantz] created a tool called Internal Blue that aims to be a Swiss-army knife for playing around with Bluetooth at a lower level. The ground for their tool is based in three functions that are common to all Broadcom Bluetooth chipsets: one that lets you read arbitrary memory, on that lets you run it, and one that lets you write it. Well, that was easy. The rest of their work was analyzing this code, and learning how to replace the firmware with their own version. That took them a few months of hard reversing work.

In the end, Internal Blue lets them execute commands at one layer deeper — the LMP layer — easily allowing monitoring and injection. In a series of live (and successful!) demos they probe around on a Nexus 6P from a modified Nexus 5 on their desk. This is where they started digging around in the Bluetooth stack of other devices with Broadcom chipsets, and that’s where they started finding bugs.

As is often the case, [Jiska] was just poking around and found an external code handler that didn’t do bounds checking. And that meant that she could run other functions in the firmware simply by passing the address handler offset. Since they’re essentially calling functions at any location in memory, finding which functions to call with which arguments is a process of trial and error, but the ramifications of this include at least a Bluetooth module crash and reset, but can also pull such tricks as putting the Bluetooth module into “Device Under Test” mode, which should only be accessible from the device itself. All of this is before pairing with the device — just walking by is sufficient to invoke functions through the buggy handler.

All the details of this exploit aren’t yet available, because Broadcom hasn’t fixed the firmware for probably millions of devices in the wild. And one of the reasons that they haven’t fixed it is that patching the bug will disclose where the flaw lies in all of the unpatched phones, and not all vendors can be counted on to push out updates at the same time. While they focused on the Nexus 5 cellphone, which is fairly old now, it’s applicable to any device with a similar Broadcom Bluetooth chipset.

Aside from the zero-day bug here, the big story is their Bluetooth analysis framework which will surely help other researchers learn more about Bluetooth, finding more glitches and hopefully helping make Bluetooth more openly scrutinized and more secure. Now anyone with a Raspberry Pi 3/3+ or a Nexus 5, is able to turn it into a low-level Bluetooth investigation tool.

You might know [Jiska] from her previous FitBit hack. If not, be sure to check it out.

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RFID Doing More Than ID

December 30, 2018 by 25 Comments

RFID is a workhorse in industrial, commercial, and consumer markets. Passive tags, like work badges and key fobs, need a base station but not the tags. Sensors are a big market and putting sensors in places that are hard to reach, hostile, or mobile is a costly proposition. That price could drop, and the sensors could be more approachable with help from MIT’s Auto-ID Lab who are experimenting with sensor feedback to RFID devices.

Let’s pretend you want to measure the temperature inside a vat of pressurized acid. You’d rather not drill a hole in it to insert a thermometer, but a temperature sensor sealed in Pyrex that wirelessly transmits the data and never runs out of power is a permanent and cheap solution. The researchers have their sights set on glucose sensing and that news come shortly after Alphabet gave up their RFID quest to measure glucose through contact lenses. Shown the top of this article is a prototype for a Battery Assisted Passive (BAP) RFID sensor that uses commodity glucose testing strips, sending data when the electrochemical reaction occurs. It uses six of these cells in parallel to achieve a high enough peak current to trigger the transmission. But the paper (10.1109/RFID.2018.8376201 behind paywall) mentions a few strategies to improve upon this. However, it does prove the concept that the current spike from the test strips determines the time the tag is active and that can be correlated to the blood glucose detected.

How many of our own projects would instantly upgrade with the addition of a few sensors that were previously unobtainable on a hacker budget? Would beer be brewed more effectively with more monitoring? How many wearables would be feasible with battery-free attachments? The sky is the figurative limit.

Thank you, [QES] for the tip [via TechXplore]

Pushbutton → Push Notification

December 30, 2018 by 21 Comments

How many mundane devices upgrade to IoT because they let you monitor a single data point or a variable? That little nudge over the communication precipice allows you to charge 500% more. Now, if you are as handy as a Hackaday reader, you can throw a lazy afternoon at the problem and get the same effect from a “dumb” appliance. If IoT is as simple as getting a notification when your laundry is dry, or your water is boiling, all you really need is a WiFi device and a push notification, right? Does it need to be more complicated than that? [Gianni] believes it is that simple (machine translation) and has built up an easy-to-implement version on Raspberry Pi, Arduino, and ESP8266.

[Gianni] leverages the aptly named Pushover (a paid app with a 1-week trial period) to convert your bits, bytes, words, or strings to a push notification. This idea is born of the desire for a home security system which doesn’t require constant monitoring but instead alerts you to problems. The minimum requirement you need is for your phone to chime with a notification saying, “Your front window sensor has been tripped.” Now it is time to launch your IP camera app or call someone nearby.

It’s not revolutionary, it may be the “Hello World” of IoT, but that is all some people need. The general idea is the same no matter the framework you want to use. For instance, if you Google Suite account, you can set up a chatroom just for your alert notifications; Google’s quickstart takes about 3 minutes to test it out in Python. The same setup is also available for Slack, and [Tom Nardi] did a guide for doing this with Discord. These tackle the receiving side, but the sending side is really flexible too — that MQTT broker you built could easily be the source of the alerts.

Build a handful of these in a weekend and keep them nearby to step up your next project to IoT status with a couple of solder joints. Maybe it will be a motion sensor for your own security system.

Starlite: Super Material That Protects Hands From Pesky Blowtorches

December 30, 2018 by 41 Comments

A super-material that’s non-toxic, highly flame resistant, and a good enough insulator, you can literally hold fire in your hand? Our interest was definitely caught by [NightHawkInLight] and his recent video about Starlite, embedded below the break.

Starlite was the brainchild of English hairdresser, [Maurice Ward]. The famous demo was an egg, coated in Starlite, and blasted with a blowtorch for a full 5 minutes. After heating, he cracked the egg to show it still raw. The inventor died in 2011, and apparently the recipe for Starlite died with him.

[NightHawkInLight] realized he had already made something very similar, the Pharoah’s Serpent demonstration, also known as a black snake. In both examples, a carbon foam is produced, providing flame resistance and insulation. A bit of trial and error later, and he’s out doing the original Starlight demo, pointing the blow torch at his hand instead of an egg.

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The Very Slow Movie Player Does It With E-Ink

December 30, 2018 by 18 Comments

Most displays are looking to play things faster. We’ve got movies at 60 frames per second, and gaming displays that run at 144 fps. But what about moving in the other direction? [Bryan Boyer] wanted to try this out, so he built the VSMP, or Very Slow Movie Player. It’s a neat device that plays back a movie at about 24 fph (frames per hour) on an e-ink display to demonstrate something that [Bryan] calls Slow Seeing, which, he says “helps you see yourself against the smear of time.” A traditional epic-length movie is now going to run you greater than 8,000 hours of viewing.

Artistic considerations aside, it’s an interesting device from a technical point of view. [Bryan] built it from a 7.4-inch e-ink display from Pervasive Displays. The controller is connected to a Raspberry Pi Zero, which is running a Python script to convert a frame of the movie file into a dithered file, then send it to the display. Because the Pi Zero isn’t a very fast computer, this takes some time, and thus the slow speed of the VSMP. Originally, [Bryan] had set it up to run as fast as the system could manage, which was about 25 seconds per frame, or about 2 frames per minute. He decided to slow it down a bit further to the more attractive multiple of 24 frames per hour to contrast with the 24 frames per second of the original movie. He did this by using a CRON job that kicks of the conversion script once every 2.5 minutes and increments the frame counter. All of this is topped off with a nice 3D-printed case that has a lovely interference pattern to make a rather neat and intriguing project.

Perhaps the best part of this is see a time-lapse of the VSMP — life moves quickly around it while 2001: A Space Odyssey plays at normal speed.

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