Hackaday Links: January 5, 2020

It looks like the third decade of the 21st century is off to a bit of a weird start, at least in the middle of the United States. There, for the past several weeks, mysterious squads of multicopters have taken to the night sky for reasons unknown. Witnesses on the ground report seeing both solo aircraft and packs of them, mostly just hovering in the night sky. In mid-December when the nightly airshow started, the drones seemed to be moving in a grid-search pattern, but that seems to have changed since then. These are not racing drones, nor are they DJI Mavics; witnesses report them to be 6′ (2 meters) in diameter and capable of staying aloft for 90 minutes. These are serious professional machines, not kiddies on a lark. So far, none of the usual government entities have taken responsibility for the flights, so speculation is all anyone has as to their nature. We’d like to imagine someone from our community will get out there with radio direction finding gear to locate the operators and get some answers.

We all know that water and electricity don’t mix terribly well, but thanks to the seminal work of White, Pinkman et al (2009), we also know that magnets and hard drives are a bad combination. But that didn’t stop Luigo Rizzo from using a magnet to recover data from a hard drive. He reports that the SATA drive had been in continuous use for more than 11 years when it failed to recover after a power outage. The spindle would turn but the heads wouldn’t move, despite several rounds of percussive maintenance. Reasoning that the moving coil head mechanism might need a magnetic jump-start, he probed the hard drive case with a magnetic parts holder until the head started moving again. He was then able to recover the data and retire the drive. Seems like a great tip to file away for a bad day.

It seems like we’re getting closer to a Star Trek future every day. No, we probably won’t get warp drives or transporters anytime soon, and if we’re lucky velour tunics and Spandex unitards won’t be making a fashion statement either. But we may get something like Dr. McCoy’s medical scanner thanks to work out of MIT using lasers to conduct a non-contact medical ultrasound study. Ultrasound exams usually require a transducer to send sound waves into the body and pick up the echoes from different structures, with the sound coupled to the body through an impedance-matching gel. The non-contact method uses pulsed IR lasers to penetrate the skin and interact with blood vessels. The pulses rapidly heat and expand the blood vessels, effectively turning them into ultrasonic transducers. The sound waves bounce off of other structures and head back to the surface, where they cause vibrations that can be detected by a second laser that’s essentially a sophisticated motion sensor. There’s still plenty of work to do to refine the technique, but it’s an exciting development in medical imaging.

And finally, it may actually be that the future is less Star Trek more WALL-E in the unlikely event that Segway’s new S-Pod personal vehicle becomes popular. The two-wheel self-balancing personal mobility device is somewhat like a sitting Segway, except that instead of leaning to steer it, the operator uses a joystick. Said to be inspired by the decidedly not Tyrannosaurus rex-proof “Gyrosphere” from Jurassic World, the vehicle tops out at 24 miles per hour (39 km/h). We’re not sure what potential market for these things would need performance like that – it seems a bit fast for the getting around the supermarket and a bit slow for keeping up with city traffic. So it’s a little puzzling, although it’s clearly easier to fully automate than a stand-up Segway.

Online Chip Reference Trims The Fat

partsdb

Quick: which pins are used for I2C on an ATmega168 microcontroller?

If you’re a true alpha geek you probably already know the answer. For the rest of us, ChipDB is the greatest thing since the resistor color code cheat sheet. It’s an online database of component pinouts: common Atmel microcontrollers, the peripheral ICs sold by SparkFun, and most of the 4000, 7400 and LMxxx series parts.

The streamlined interface, reminiscent of Google, returns just the essential information much quicker than rummaging through PDF datasheets (which can also be downloaded there if you need them). And the output, being based on simple text and CSS, renders quite well on any device, even a dinky smartphone screen.

Site developer [Matt Sarnoff] summarizes and calls upon the hacking community to help expand the database:

“The goal of my site isn’t to be some comprehensive database like Octopart; just a quick reference for the chips most commonly used by hobbyists. However, entries still have to be copied in manually. If anyone’s interested in adding their favorite chips, they can request a free account and use the (very primitive at this point) part editor. Submissions are currently moderated, since this is an alpha-stage project.”

Homeland Security Issues Policy On Laptop Seizures


The US Department of Homeland Security recently disclosed a new policy that allows agents to seize laptops, or anything capable of storing information, “for a reasonable period of time”. Okay, so this seems normal; A government agency is declaring they may confiscate personal property. However, the strange part of this story is that under this policy, federal agents can confiscate these things without any suspicion of wrong doing or any reason what so ever. So what happens to your personal data after they seize your laptop? Apparently they share the data with federal agencies, and in some cases the private sector, as additional services such as file decryption or translation are needed. While this may seem like a major violation of privacy, it is important to note that this policy only applies to people entering the United States. However given the direction that our federal government is moving in the area of security, it wouldn’t surprise me if this policy will soon apply for domestic flights as well.

[photo: postmodern sleaze]

[via eff.org]