A Birthday Cake For A Retrocomputer Designer

October 25, 2024 by Jenny List 6 Comments

When making a birthday cake a bit more personal, one can create a novelty themed confection appropriate for the lucky recipient. In the case of [Spencer Owen], who you may know as the creator of the RC2014 retrocomputing ecosystem, it was appropriate to have one of the little machines at work somewhere, so [peahen] did just that. The result is a cake in the shape of an IMSAI 8080 microcomputer, but it does more than just look the part. This is a working replica of the classic machine, powered as you might expect by an RC2014 sitting next to it.

The lights are a set of addressable LEDs, and the switches are made from appropriately colored sweets. Sadly the plan to make these capacitive touch switched failed as the wiring became buried in the icing, but the LEDs deserve a second look. They’re encased in translucent heatshrink sleeving which is embedded under a layer of white icing, which is translucent enough, but on top for the classic panel light look are a set of edible cake-maker’s jewels. Best of all while all except the electronics is edible, the front panel is robust enough to have been removed from the cake in one and thus will live on.

We rather like the idea of electronics meeting sugarcraft, because fondant is a surprisingly versatile medium that deserves attention much further than just confectionery. We remember it being a popular cheap way to experiment with 3D printing back at the dawn of open source printers, and it still has some potential. Meanwhile if you’ve not seen the RC2014 we reviewed its original version back in 2016, and since then it’s evolved to become an ecosystem in its own right.

Putting The New CryoGrip Build Plate To The Test

October 25, 2024 by Dave Rowntree 15 Comments

BIQU has released a new line of low-temperature build plates that look to be the next step in 3D printing’s iteration—or so YouTuber Printing Perspective thinks after reviewing one. The Cryogrip Pro is designed for the Bambu X1, P1, and A1 series of printers but could easily be adapted for other magnetic-bed machines.

The bed adhesion strength when cold is immense!

The idea of the new material is to reduce the need for high bed temperatures, keeping enclosure temperatures low. As some enclosed printer owners may know, trying to print PLA and even PETG with the door closed can be troublesome due to how slowly these materials cool. Too high an ambient temperature can wreak havoc with this cooling process, even leading to nozzle-clogging.

The new build plate purports to enable low, even ambient bed temperatures, still with maximum adhesion. Two versions are available, with the ‘frostbite’ version intended for only PLA and PETG but having the best adhesion properties. A more general-purpose version, the ‘glacier’ sacrifices a little bed adhesion but gains the ability to handle a much wider range of materials.

An initial test with a decent-sized print showed that the bed adhesion was excellent, but after removing the print, it still looked warped. The theory was that it was due to how consistently the magnetic build plate was attached to the printer bed plate, which was now the limiting factor. Switching to a different printer seemed to ‘fix’ that issue, but that was really only needed to continue the build plate review.

They demonstrated a common issue with high-grip build plates: what happens when you try to remove the print. Obviously, magnetic build plates are designed to be removed and flexed to pop off the print, and this one is no different. The extreme adhesion, even at ambient temperature, does mean it’s even more essential to flex that plate, and thin prints will be troublesome. We guess that if these plates allow the door to be kept closed, then there are quite a few advantages, namely lower operating noise and improved filtration to keep those nasty nanoparticles in check. And low bed temperatures mean lower energy consumption, which is got to be a good thing. Don’t underestimate how much power that beefy bed heater needs!

Ever wondered what mini QR-code-like tags are on the high-end build plates? We’ve got the answer. And now that you’ve got a pile of different build plates, how do you store them and keep them clean? With this neat gadget!

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Custom Drone Software Searches, Rescues

October 24, 2024 by Bryan Cockfield 17 Comments

When a new technology first arrives in people’s hands, it often takes a bit of time before the full capabilities of that technology are realized. In much the same way that many early Internet users simply used it to replace snail mail, or early smartphones were used as more convenient methods for messaging and calling than their flip-phone cousins, autonomous drones also took a little bit of time before their capabilities became fully realized. While some initially used them as a drop-in replacement for things like aerial photography, a group of mountain rescue volunteers in the United Kingdom realized that they could be put to work in more efficient ways suited to their unique abilities and have been behind a bit of a revolution in the search-and-rescue community.

The first search-and-rescue groups using drones to help in their efforts generally used them to search in the same way a helicopter would have been used in the past, only with less expense. But the effort involved is still the same; a human still needed to do the searching themselves. The group in the UK devised an improved system to take the human effort out of the equation by sending a drone to fly autonomously over piece of mountainous terrain and take images of the ground in such a way that any one thing would be present in many individual images. From there, the drone would fly back to its base station where an operator could download the images and run them through a computer program which would analyse the images and look for outliers in the colors of the individual pixels. Generally, humans tend to stand out against their backgrounds in ways that computers are good at spotting while humans themselves might not notice at all, and in the group’s first efforts to locate a missing person they were able to locate them almost immediately using this technology.

Although the system is built on a mapping system somewhat unique to the UK, the group has not attempted to commercialize the system. MR Maps, the software underpinning this new feature, has been free to use for anyone who wants to use it. And for those just starting out in this field, it’s also worth pointing out that location services offered by modern technologies in rugged terrain like this can often be misleading, and won’t be as straightforward of a solution to the problem as one might think.

Using An OLED Display’s Light For Embedded Sensors

October 24, 2024 by Maya Posch 8 Comments

These days displays are increasingly expected to be bidirectional devices, accepting not only touch inputs, but also to integrate fingerprint sensing and even somehow combine a camera with a display without punching a hole through said display. Used primarily on smartphone displays, these attempts have been met with varying degrees of success. But a paper published in the Communications Engineering journal describes a version which combines an OLED with photosensors in the same structure — a design that may provide a way to make such features much more effective.

The article by [Chul Kim] and colleagues of the Samsung Display Research Center in South Korea the construction of these bidirectional OLED displays is described, featuring the standard OLED pixels as well as an organic photodiode (OPD) placed side-by-side. Focusing on the OLED’s green light for its absorption characteristics with the human skin, the researchers were able to use the produced OLED/OPD hybrid display for fingerprint recognition, as well as a range of cardiovascular markers, including heart rate, blood pressure, etc.

The basic principle behind these measurements involves photoplethysmography, which is commonly used in commercially available pulse oximeters. Before these hybrid displays can make their way into commercial devices, there are still a few technical challenges to deal with, in particular electrical and optical leakage. The sample demonstrated appears to work well in this regard, but the proof is always in the transition from the lab to mass-production. We have to admit that it would be rather cool to have a display that can also handle touch, fingerprints and record PPG data without any special layers or sensor chips.

Mini Robotic Arm Lets You Start Your Own Mini Assembly Line

October 24, 2024 by Navarre Bartz 25 Comments

Automating tasks with a robot sounds appealing, but not everyone has the budget for an Aismo or Kuka. [FABRI Creator] has a great tutorial on how to build your own mini robotic arm for small, repeatable tasks.

Walking us through the entire build, step-by-step, [FABRI Creator] shows us how to populate the custom-designed PCB and where to put every servo motor and potentiometer to bring the creation to life. This seems like a great project to start with if you haven’t branched out into motion systems before since it’s a useful build without anything too complicated to trip up the beginner.

Beyond the usual ability to use the arm to perform tasks, this particular device uses an Arduino Nano to allow you to record a set of positions as you move the arm and to replay it over and over. The video shows the arm putting rings on a stand, but we can think of all kinds of small tasks that it could accomplish for us, letting us get back to writing or hacking.

If controlling a robot arm with potentiometers sounds familiar, maybe you remember this robot arm with an arm-shaped controller.

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Simple PCB Repairs Keep Old Vehicle Out Of The Crusher

October 24, 2024 by Dan Maloney 21 Comments

For those of us devoted to keeping an older vehicle on the road, the struggle is real. We know that at some point, a part will go bad and we’ll learn that it’s no longer available from the dealer or in the aftermarket, at least at a reasonable cost. We might get lucky and find a replacement at the boneyard, but if not — well, it was nice knowing ya, faithful chariot.

It doesn’t have to be that way, though, at least if the wonky part is one of the many computer modules found in most cars made in the last few decades. Sometimes they can be repaired, as with this engine control module from a Ford F350 pickup. Admittedly, [jeffescortlx] got pretty lucky with this module, which with its trio of obviously defective electrolytics practically diagnosed itself. He also had the advantage of the module’s mid-90s technology, which still relied heavily on through-hole parts, making the repair easier.

Unfortunately, his luck stopped there, as the caps had released the schmoo and corroded quite a few traces on the PCB. Complicating the repair was the conformal coating on everything, a common problem on any electronics used in rough environments. It took a bit of probing and poking to locate all the open traces, which included a mystery trace far away from any of the leaky caps. Magnet wire was used to repair the damaged traces, the caps were replaced with new ones, and everything got a fresh coat of brush-on conformal coating.

Simple though they may be, we really enjoy these successful vehicle module repairs because they give us hope that when the day eventually comes, we’ll stand a chance of being able to perform some repair heroics. And it’s nice to know that something as simple as fixing a dead dashboard cluster can keep a car out of the crusher.

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Artificial Intelligence Runs On Arduino

October 24, 2024 by Bryan Cockfield 23 Comments

Fundamentally, an artificial intelligence (AI) is nothing more than a system that takes a series of inputs, makes some prediction, and then outputs that information. Of course, the types of AI in the news right now can handle a huge number of inputs and need server farms’ worth of compute to generate outputs of various forms, but at a basic level, there’s no reason a purpose-built AI can’t run on much less powerful hardware. As a demonstration, and to win a bet with a friend, [mondal3011] got an artificial intelligence up and running on an Arduino.

This AI isn’t going to do anything as complex as generate images or write clunky preambles to every recipe on the Internet, but it is still a functional and useful piece of software. This one specifically handles the brightness of a single lamp, taking user input on acceptable brightness ranges in the room and outputting what it thinks the brightness of the lamp should be to match the user’s preferences. [mondal3011] also builds a set of training data for the AI to learn from, taking the lamp to various places around the house and letting it figure out where to set the brightness on its own. The training data is run through a linear regression model in Python which generates the function that the Arduino needs to automatically operate the lamp.

Although this isn’t the most complex model, it does go a long way to demonstrating the basic principles of using artificial intelligence to build a useful and working model, and then taking that model into the real world. Note also that the model is generated on a more powerful computer before being ported over to the microcontroller platform. But that’s all par for the course in AI and machine learning. If you’re looking to take a step up from here, we’d recommend this robot that uses neural networks to learn how to walk.