Curated

76 Articles

Hackaday’s finest original content articles curated by the Hackaday editors

The Honda Takedown: How A Global Brand Failed To Read The Room

April 21, 2022 by 141 Comments

Perhaps the story of the moment in the world of 3D printing concerns a Japanese manufacturer of cars and motorcycles. Honda has sent a takedown notice requesting the removal of models starting with the word “Honda” to the popular 3D printing model repository site Printables. It’s left in its wake puzzlement, disappointment, and some anger, but what’s really going on? Perhaps it’s time to examine what has happened and to ponder what it means for those who put online printable parts and accessories for cars or any other item manufactured by a large corporation.

If You Make Something, What Rights Do You Have?

Soichiro Honda with his 1964 Formula 1 car
Soichiro Honda, famous for being an engineer rather than a serial litigator. Roderick Eime, CC BY 2.0.

The story is that as far as we can glean from reports online, the takedown notice was sent only to Printables by the European arm of Honda, and was pretty wide-ranging with any Honda-related model in its scope. Printables complied with it, but as this is being written there are plenty of such models available from Thingiverse and other model repository sites.

Anyone who makes a career in content creation has by necessity to have a working knowledge of copyright and intellectual property law as it’s easy for the unwary to end up the subject of a nasty letter, so here at Hackaday while we’re not lawyers this is a subject on which we have some professional experience. What follows then is our take based on that experience, our view on Honda’s motivation, and whether those of you who put up 3D models have anything to worry about. Continue reading “The Honda Takedown: How A Global Brand Failed To Read The Room” →

Copper: Rectifying AC A Century Ago

April 20, 2022 by 34 Comments

[Robert Murray-Smith] presents for us an interesting electronic device from years gone by, before the advent of Silicon semiconductors, the humble metal oxide rectifier. After the electronic dust had settled following the brutal AC/DC current wars of the late 19th century — involving Edison, Tesla and Westinghouse to name a few of the ringleaders — AC was the eventual winner. But there was a problem. It’s straightforward to step down the high voltage AC from the distribution network to a more manageable level with a transformer, and feed that straight into devices which can consume alternating current such as light bulbs and electrical heaters. But other devices really want DC, and to get that, you need a rectifier.

It turns out, that even in those early days, we had semiconductor devices which could perform this operation, based not upon silicon or germanium, but copper. Copper (I) Oxide is a naturally occurring P-type semiconductor, which can be easily constructed by heating a copper sheet in a flame, and scraping off the outer layer of Copper (II) Oxide leaving the active layer below. Simply making contact to a piece of steel is sufficient to complete the device.

Obviously a practical rectifier is a bit harder to make, with a degree of control required, but you get the idea. A CuO metal rectifier can rectify as well as operate as a thermopile, and even as a solar cell, it’s just been forgotten about once we got all excited about silicon.

Other similar metallic rectifiers also saw some action, such as the Selenium rectifier, based on the properties of a Cadmium Selenide – Selenium interface, which forms an NP junction, albeit one that can’t handle as much power as good old copper. One final device, which was a bit of an improvement upon the original CuO rectifiers, was based upon a stack of Copper Sulphide/Magnesium metal plates, but they came along too late. Once we discovered the wonders of germanium and silicon, it was consigned to the history books before it really saw wide adoption.

We’ve covered CuO rectifiers before, but the Copper Sulphide/Magnesium rectifier is new to us. And if you’re interested in yet more ways to steer electrons in one direction, checkout our coverage of the history of the diode.

Continue reading “Copper: Rectifying AC A Century Ago” →

Commodore C64: The Most Popular Home Computer Ever Turns 40

April 20, 2022 by 107 Comments

This year marks the anniversary of the most popular selling home computer ever, the Commodore 64, which made its debut in 1982. Note that I am saying “home computer” and not personal computer (PC) because back then the term PC was not yet in use for home computer users.

Some of you have probably not heard of Commodore, which is kind of sad, though there is a simple reason why — Commodore is no longer around to maintain its legacy. If one were to watch a documentary about the 1980s they may see a picture of an Apple computer or its founders but most likely would not see a picture of a Commodore computer in spite of selling tens of millions of units.

To understand the success of the C64 I would first back up and talk about the fabled era of home computers which starts with understanding the microprocessor of the day, the venerable 6502. Check out the video and follow along below.

Continue reading “Commodore C64: The Most Popular Home Computer Ever Turns 40” →

Arm Pumps Up The Volume With Mbed And A Potentiometer

April 19, 2022 by 7 Comments

Last time, I told you how to get started with the “Black Pill” STM32F411 board using the Mbed OS. The example program, admittedly, didn’t use many of the features of the OS, unless you count what the USB serial port driver uses behind the scenes. However, this time, we’ll make a practical toy that lets you adjust your PC’s volume level with a pot.

The Black Pill module on a breadboard.

The Black Pill is a good choice for this application since it has analog inputs and can act as a USB keyboard. In fact, the Mbed OS has drivers for all kinds of USB devices. We’ve seen the serial port, but you can also look like a mass storage device or a mouse, for example. Just for practice, we’ll create two threads of execution. One will read the pot and send a message over to the other thread. That thread will communicate with the PC as a USB keyboard. Any computer that understands media keys on a keyboard should work with the device.

Threads

Creating threads is very simple. For many cases, you just define a void function that takes no arguments and use it with a Thread object:

readknobThread.start(vol_thread);

Of course, the function shouldn’t return unless you want the thread to end. As I mentioned in the last post, you can sleep with the ThisThread::sleep_for call. There is also a yield call if you simply want to give up the time slice without sleeping for a specific amount of time.

Continue reading “Arm Pumps Up The Volume With Mbed And A Potentiometer” →

Mercury Thrusters: A Worldwide Disaster Averted Just In Time

April 18, 2022 by 60 Comments

The field of space vehicle design is obsessed with efficiency by necessity. The cost to do anything in space is astronomical, and also heavily tied to launch weight. Thus, any technology or technique that can bring those figures down is prime for exploitation.

In recent years, mercury thrusters promised to be one such technology. The only catch was the potentially-ruinous environmental cost. Today, we’ll look at the benefits of mercury thrusters, and how they came to be outlawed in short order.

Continue reading “Mercury Thrusters: A Worldwide Disaster Averted Just In Time” →

Less Is More — Or How To Replace A $25,000 Bomb Sight For 20 Cents

April 14, 2022 by 66 Comments

Depending on who you ask, the Norden bombsight was either the highest of high tech during World War II, or an overhyped failure that provided jobs and money for government contractors. Either way, it was super top secret in its day. It was also expensive. They cost about $25,000 each and the whole program came in at well over a billion dollars. The security was over the top. When not flying, the bombsight was removed from the plane and locked in a vault. There was a pyro device that would self-destruct the unit if it were in danger of being captured. So why did one of the most famous missions of World War II fly with the Norden replaced by 20 cents worth of machined metal? Good question.

You often hear the expression “less is more” and, in this case, it is an accurate idea. I frequently say, though, that “just enough is more.” In this case, though, less was actually just enough. There were three reasons that one famous mission in the Pacific theater didn’t fly the Norden. It all had to do with morale, technology, and secrecy.

Continue reading “Less Is More — Or How To Replace A $25,000 Bomb Sight For 20 Cents” →

Great Beginnings: The Antikythera Mechanism Gets A “Day Zero”

April 14, 2022 by 29 Comments

When an unknown genius sat down more than 2,000 years ago to design and build an astronomical instrument, chances are good that he or she didn’t think that entire academic institutions devoted to solving its mysteries would one day be established. But such is the enduring nature of the Antikythera mechanism, the gift from antiquity that keeps on giving long after being dredged up from a shipwreck in the Aegean Sea.

And now, new research on the ancient mechanism reveals that like other mechanical calendars, the Antikythera mechanism has a “day zero,” or a minimum possible date that it can display. The analysis by a team led by [Aristeidis Voulgaris] gets deep into the weeds of astronomical cycles, which the mechanism was designed to simulate using up to 37 separate gears, 30 of which have been found. The cycle of concern is the saros, a 223 lunar month cycle of alignments between the Earth, Sun, and Moon. The saros can be used to predict eclipses, astronomical events of immense importance in antiquity, particularly annular eclipses, which occur when the Moon is at apogee and therefore eclipses less of the Sun’s surface.

The researchers looked at historical annular eclipse data and found that saros cycle 58 had a particularly long annular eclipse, on 23 December 178 BCE. The eclipse would have been visible at sunrise in the eastern Mediterranean, and coupled with other astronomical goodies, like the proximity to the winter solstice, the Sun entering Capricorn, and the Moon being new and at apogee, was probably so culturally significant to the builder that it could serve as the initial date for calibrating all the mechanisms pointers and dials.

Others differ with that take, of course, saying that the evidence points even further back, to a start date in the summer of 204 BCE. In any case, if like us you can’t get enough Antikythera, be sure to check out our overview of the mechanism, plus [Clickspring]’s exploration of methods perhaps used to build it.