Hackaday Podcast 040: 3D Printed Everything, Strength V Toughness, Blades Of Fiber, And What Can’t Coffee Do?

October 18, 2019 by Mike Szczys No comments

Hackaday Editors Mike Szczys and Elliot Williams opine on the coolest hacks we saw this week. This episode is heavy with 3D printing as Prusa released a new, smaller printer, printed gearboxes continue to impress us with their power and design, hoverboards are turned into tanks, and researchers suggest you pour used coffee grounds into your prints. Don’t throw out those “toy” computers, they may be hiding vintage processors. And we have a pair of fantastic articles that cover the rise and fall of forest fire watchtowers, and raise the question of where all those wind turbine blades will go when we’re done with them.

Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!

Take a look at the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Direct download (60 MB or so.)

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This Week In Security: A Digital Café Américain, The Linux Bugs That Weren’t, The Great Nation, And More

October 18, 2019 by Jonathan Bennett 16 Comments

A government is going after a human rights activists in Morocco. It sounds familiar, but I don’t think Humphrey Bogart is running the gin joint this time around.

Questionable Casablanca references aside, Amnesty International has reported another attack against human rights workers. In this case, a pair of Moroccan activists were targeted with what appears to be NSO’s Pegasus malware suite. Researchers identified text message phishing that led to malicious web pages, as well as HTTP man in the middle attacks against their mobile devices. Once the target was successfully directed to the malicious site, A collection of zero-day vulnerabilities were used to compromise the phone with the NSO malware.

NSO is an Israeli company that specializes in building malware and other cybersecurity tools for governments. As you can imagine, this specialization has earned NSO the scorn of quite a few organizations. NSO claims to have a policy framework in place that allows them to evaluate and terminate the use of their software when it is deemed illegal or abusive, but due to the nature of their contracts, that process is anything but transparent. Continue reading “This Week In Security: A Digital Café Américain, The Linux Bugs That Weren’t, The Great Nation, And More” →

Worried About Bats In Your Belfry? A Tale Of Two Bat Detectors

October 17, 2019 by Pat Whetman 33 Comments

As somebody who loves technology and wildlife and also needs to develop an old farmhouse, going down the bat detector rabbit hole was a journey hard to resist. Bats are ideal animals for hackers to monitor as they emit ultrasonic frequencies from their mouths and noses to communicate with each other, detect their prey and navigate their way around obstacles such as trees — all done in pitch black darkness. On a slight downside, many species just love to make their homes in derelict buildings and, being protected here in the EU, developers need to make a rigorous survey to ensure as best as possible that there are no bats roosting in the site.

Obviously, the authorities require a professional independent survey, but there’s still plenty of opportunity for hacker participation by performing a ‘pre-survey’. Finding bat roosts with DIY detectors will tell us immediately if there is a problem, and give us a head start on rethinking our plans.

As can be expected, bat detectors come in all shapes and sizes, using various electrickery techniques to make them cheaper to build or easier to use. There are four different techniques most popularly used in bat detectors.

Heterodyne: rather like tuning a radio, pitch is reduced without slowing the call down.
Time expansion: chunks of data are slowed down to human audible frequencies.
Frequency division: uses a digital counter IC to divide the frequency down in real time.
Full spectrum: the full acoustic spectrum is recorded as a wav file.

Fortunately, recent advances in technology have now enabled manufacturers to produce relatively cheap full spectrum devices, which give the best resolution and the best chances of identifying the actual bat species.

DIY bat detectors tend to be of the frequency division type and are great for helping spot bats emerging from buildings. An audible noise from a speaker or headphones can prompt us to confirm that the fleeting black shape that we glimpsed was actually a bat and not a moth in the foreground. I used one of these detectors in conjunction with a video recorder to confirm that a bat was indeed NOT exiting from an old chimney pot. Phew!

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RTFM: ADCs And DACs

October 16, 2019 by Ted Yapo 11 Comments

It’s tough to find a project these days that doesn’t use an analog-to-digital converter (ADC) or digital-to-analog converter (DAC) for something. Whether these converters come as built-in peripherals on a microcontroller, or as separate devices connected over SPI, I2C, or parallel buses, all these converters share some common attributes, and knowing how to read the specs on them can save you a lot of headaches when it comes to getting things working properly.

There are some key things to know about these devices, and the first time you try to navigate a datasheet on one, you may find yourself a bit confused. Let’s take a deep dive into the static (DC) properties of these converters — the AC performance is complex enough to warrant its own follow-up article.

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How To Build The Strongest Arches

October 15, 2019 by Sharon Lin 13 Comments

When it comes to architectural features, there are probably not many as quintessentially memorable as arches. From the simplicity of the curved structure to the seemingly impossible task of a supposedly collapsable shape supporting so much weight in mid-air, they’ve naturally fascinated architects for generations.

For civil engineers, learning to calculate the forces acting on an arch, the material strength and properties, and the weight distribution across several arches may be familiar, but for anyone with only a basic physics and CAD background, it’s easy to take arches for granted. After all, they grace the Roman aqueducts, the Great Wall of China, and are even present in nature at Arches National Park. We see them in cathedrals, mosques, gateways, and even memorialized in the case of the St. Louis Gateway Arch. Even the circular construction of watch towers and wells, as well as our own rib cages, are due to the properties of arches.

But what really goes into constructing a strong arch? Continue reading “How To Build The Strongest Arches” →

Linux Fu: Python GUIs For Command Line Programs (Almost) Instantly

October 14, 2019 by Al Williams 7 Comments

Not every programmer likes creating GUI code. Most hacker types don’t mind a command line interface, but very few ordinary users appreciate them. However, if you write command line programs in Python, Gooey can help. By leveraging some Python features and a common Python idiom, you can convert a command line program into a GUI with very little effort.

The idea is pretty simple. Nearly all command line Python programs use argparse to simplify picking options and arguments off the command line as well as providing some help. The Gooey decorator picks up all your options and arguments and creates a GUI for it. You can make it more complicated if you want to change specific things, but if you are happy with the defaults, there’s not much else to it.

At first, this article might seem like a Python Fu and not a Linux Fu, since — at first — we are going to focus on Python. But just stand by and you’ll see how this can do a lot of things on many operating systems, including Linux.

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Hacking Diabetes Hack Chat

October 14, 2019 by Dan Maloney 2 Comments

Join us on Wednesday, October 16 at noon Pacific for the Hacking Diabetes Hack Chat with Dana Lewis!

When your child is newly diagnosed with Type 1 diabetes (T1D), everyone is quick to point out, “It’s a great time to be a diabetic.” To some degree, that’s true; thanks to genetically engineered insulin, more frequent or even continuous glucose monitoring (CGM), and insulin infusion pumps, diabetics can now avoid many of the truly terrifying complications of a life lived with chronically elevated blood glucose, like heart disease, kidney failure, blindness, and amputations.

Despite these advances, managing T1D can be an overwhelming task. Every bite of food, every minute of exercise, and every metabolic challenge has to be factored into the calculations for how much insulin to take. Diabetics learn to “think like a pancreas,” but it’s never good enough, and the long-promised day of a true artificial pancreas always seems to remain five years in the future.

Dana Lewis is one diabetic who decided not to wait. After realizing that she could get data from her CGM, she built a system to allow friends and family to monitor her blood glucose readings remotely. With the addition of a Raspberry Pi and some predictive algorithms, she later built an open-source artificial pancreas, which she uses every day. And now she’s helping others take control of their diabetes and build their own devices through OpenAPS.org.

Join us on the Hack Chat as Dana drops by to discuss OpenAPS and her artificial pancreas. We’ll find out what her background is – spoiler alert: she wasn’t a hacker when she started this – what challenges she faced, the state of the OpenAPS project, and where she sees the artificial pancreas going.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, October 16 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

[Dana Lewis image source: GeekWire]

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