Fail Of The Week — Accidental Demagnetization

October 27, 2017 by Bob Baddeley 41 Comments

There’s a trick in the world of plastic enclosures. The threaded insert is a small cylinder of metal with threads on the inside and a rough edge on the outside. To make a plastic part with a hole for securely connecting bolts that can be repeatedly screwed without destroying the plastic, you take the threaded insert and press it (usually with the help of a soldering iron to heat the insert) into a hole that’s slightly smaller than the insert. The heat melts the plastic a little bit and allows for the insert to go inside. Then when it cools the insert is snugly inside the plastic, and you can attach circuit boards or other plastic parts using a bolt without stripping the screw or the insert. We’ve seen Hackaday’s [Joshua Vasquez] installing threaded inserts with an iron, as well as in a few other projects.

This trick is neat. And I’ve now proven that it does not work with neodymium magnets.

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Hyperspectral Imaging – Seeing The Unseeable

October 25, 2017 by Will Sweatman 25 Comments

They say that a picture is worth a thousand words. But what is a picture exactly? One definition would be a perfect reflection of what we see, like one taken with a basic camera. Our view of the natural world is constrained to a bandwidth of 400 to 700 nanometers within the electromagnetic spectrum, so our cameras produce images within this same bandwidth.

For example, if I take a picture of a yellow flower with my phone, the image will look just about how I saw it with my own eyes. But what if we could see the flower from a different part of the electromagnetic spectrum? What if we could see less than 400 nm or greater than 700 nm? A bee, like many other insects, can see in the ultraviolet part of the spectrum which occupies the area below 400 nm. This “yellow” flower looks drastically different to us versus a bee.

In this article, we’re going to explore how images can be produced to show spectral information outside of our limited visual capacity, and take a look at the multi-spectral cameras used to make them. We’ll find that while it may be true that an image is worth a thousand words, it is also true that an image taken with a hyperspectral camera can be worth hundreds of thousands, if not millions, of useful data points. Continue reading “Hyperspectral Imaging – Seeing The Unseeable” →

Active Discussion About Passive Components

October 16, 2017 by Bob Baddeley 35 Comments

People talk about active and passive components like they are two distinct classes of electronic parts. When sourcing components on a BOM, you have the passives, which are the little things that are cheaper than a dime a dozen, and then the rest that make up the bulk of the cost. Diodes and transistors definitely fall into the cheap little things category, but aren’t necessarily passive components, so what IS the difference?

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Building The Hackaday Superconference Badge

October 11, 2017 by Brian Benchoff 36 Comments

The best hardware conference is just a few weeks away. This is the Hackaday Superconference, and it’s two days of talks, an extra day of festivities, soldering irons, and an epic hardware badge. We’ve been working on this badge for a while now, and it’s finally time to share some early details. This is an awesome badge and a great example of how to manufacture electronics on an extremely compressed timetable. This is badgelife, the hardware demoscene of electronic conference badges.

So, what does this badge do? It’s a camera. It has games, and it’s designed by [Mike Harrison] of Mike’s Electric Stuff. He designed and prototyped this badge in a single weekend. On board is a PIC32 microcontroller, an OV9650 camera module, and a bright, crisp 128×128 resolution color OLED display. Tie everything together with a few buttons, and you have a badge that’s really incredible.

So, how do you get one? You’ve got to come to the Hackaday Superconference. This year we’re doing things a bit differently and opening the doors a day early to get the hacker village started with badge hacking topped off by a party that evening and everyone coming to Supercon is invited! This is a badge full of games, puzzles, and video capture and isn’t something to miss. We have less than 30 tickets left so grab your ticket now and read on.

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Ben Franklin’s Weak Motor And Other Forgotten Locomotion

October 3, 2017 by Steven Dufresne 11 Comments

Most of the electric motors we see these days are of the electromagnetic variety, and for good reason: they’re powerful. But there’s a type of motor that was invented before the electromagnetic one, and of which there are many variations. Those are motors that run on high voltage, and the attraction and repulsion of charge, commonly known as electrostatic motors.

Ben Franklin — whose electric experiments are most frequently associated with flying a kite in a thunderstorm — built and tested one such high-voltage motor. It wasn’t very powerful, but was good enough for him to envision using it as a rotisserie hack. Food is a powerful motivator.

What follows is a walk through the development of various types of these motors, from the earliest ion propelled ones to the induction motors which most have never heard of before, even an HV hacker such as yours truly.

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Books You Should Read: Feynman’s Appendix To The Challenger Disaster Report

October 2, 2017 by Donald Papp 84 Comments

It isn’t really a book, but Richard Feynman’s Appendix to the Challenger Disaster Report is still definitely something you should read. It’s not particularly long, but it’s educational and relevant not just as an example of critical thinking in action, but as a reminder not to fool oneself; neither individually, nor on an organizational level. Sadly, while much was learned from the events leading to and surrounding the Challenger disaster, over thirty years later many of us can still find a lot of the same things to relate to in our own professional lives. There isn’t a single magic solution, because these problems are subtle and often masquerade as normal.

Feynman and the Challenger Disaster

Richard Feynman (1918-1988) was a Nobel Prize winning physicist and one of the best-known scientists of his time. In 1986 he somewhat reluctantly agreed to join the Rogers Commission, whose task was to investigate the Challenger disaster. The space shuttle Challenger had exploded a little more than a minute after launch, killing everyone on board. The commission’s job was to find out what had gone wrong and how it had happened, and figure out how to keep it from happening again.

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Calculus In 20 Minutes

September 28, 2017 by Al Williams 56 Comments

If you went to engineering school, you probably remember going to a lot of calculus classes. You may or may not remember a lot of calculus. If you didn’t go to engineering school, you will find that there’s an upper limit to how much electronics theory you can learn before you have to learn calculus. Now imagine Khan Academy, run by an auctioneer and done without computers. Well, you don’t have to imagine it. Thinkwell has two videos that purport to teach you calculus in twenty minutes (YouTube, embedded below).

We are going to be honest. If you need a refresher, these videos might be useful. If you have no idea how to do calculus, maybe these are going to whiz by a little fast. However, either way, the videos have some humor value both from the FedEx commercial-style delivery to the non-computerized graphics (not to mention the glass-breaking sound effects). Of course, the video is about ten years old, but that’s part of its charm.

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