PAHT-CF part printed at 45 degrees, with reinforcing bolt, post-failure. (Credit: Functional Print Friday, YouTube)The good part about FDM 3D printing is that there are so many different filament types and parameters to choose from. This is also the bad part, as it can often be hard to tell what impact a change has. Fortunately we got destructive testing to provide us with some information here. Case in point [Functional Print Friday] on YouTube recently testing out a few iterations of a replacement part for a car.
The original part was in ABS, printed horizontally in a Bambu Lab FDM printer, which had a protruding element snapped off while in use. In addition to printing a replacement in carbon fiber-reinforced nylon (PAHT-CF, i.e. PA12 instead of the typical PA6), the part was now also printed at a 45° angle. To compare it with the original ABS filament in a more favorable way, the same part was reprinted at the same angle in ABS.
Another change was to add a machine screw to the stop element of the part, which turned out to make a massive difference. Whereas the original horizontal ABS print failed early and cleanly on layer lines, the angled versions put up much more of a fight, with the machine screw-reinforced stop combined with the PA12 CF filament maxing out the first meter.
The take-away here appears to be that not only angles are good, but that adding a few strategic metal screws can do wonders, even if you’re not using a more exotic filament type.
Continue reading “Destructive Testing Of ABS And Carbon Fiber Nylon Parts” →
Wall clocks! Are they very accurate? Well, sometimes they are, and sometimes they lose minutes a day. If you’ve got one that needs calibrating, you might like this device from [Lauri Pirttiaho].
Most cheap wall clocks use very similar mechanisms based around the Lavet-type stepper motor. These are usually driven by a chip-on-board oscillator that may or may not be particularly accurate.
[Lauri] desired a way to tune up these cheap clocks by using GPS-level timing accuracy. Thus began a project based around a CY8KIT evaluation board from Cypress. The microcontroller is paired with a small character LCD as a user interface, and hooked up to a cheap GPS module with an accurate 1-pulse-per-second (1PPS) timing output. The concept is simple enough. Clock drift is measured by using counters in the microcontroller to compare the timing of the GPS 1PPS output and the pulses driving the Lavet-type stepper motor. The difference between the two can be read off the device, and used to determine if the wall clock is fast or slow. Then one need only use a trimmer capacitor to tweak the wall clock’s pulse rate in order to make it more accurate.
Few of us spend much time calibrating low-cost wall clocks to high levels of accuracy. If that sounds like a fun hobby to you, or your name is Garrus, you would probably find [Lauri]’s device remarkably useful. Believe it or not, this isn’t the first clock calibrator we’ve seen, either. Meanwhile, if you’ve brewed up your own high-accuracy timing hardware, feel free to let us know on the tipsline.
Although often glossed over, the human liver is a pretty amazing organ. Not just because it’s pretty much the sole thing that prevents our food from killing us, but also because it’s the only organ in our body that is capable of significant regeneration. This is a major boon in medicine, as you can remove most of a person’s liver and it’ll happily regrow back to its original volume. Obviously this is very convenient in the case of disease or when performing a liver transplant.
Despite tissue regeneration being very common among animals, most mammalian species have only limited regenerative ability. This means that while some species can easily regrow entire limbs and organs including eyes as well as parts of their brain, us humans and our primate cousins are lucky if we can even count on our liver to do that thing, while limbs and eyes are lost forever.
This raises many questions, including whether the deactivation of regenerative capabilities is just an evolutionary glitch, and how easily we might be able to turn it back on.
Continue reading “Be More Axolotl: How Humans May One Day Regrow Limbs And Organs” →
We’ve often thought that it must be harder than ever to learn about computers. Every year, there’s more to learn, so instead of making the gentle slope from college mainframe, to Commodore 64, to IBM PC, to NVidia supercomputer, you have to start at the end. But, really, you don’t. You can always emulate computers from simpler times, and even if you don’t need to, it can be a lot of fun.
That’s the idea behind the MonTana mini-computer. It combines “…ideas from the PDP-11, MIPS, Scott CPU, Game Boy, and JVM to make a relatively simple 16-bit computer…”
The computer runs on Java, so you can try it nearly anywhere. The console is accessed through a web browser and displays views of memory, registers, and even something that resembles a Game Boy screen. You’ll need to use assembly language until you write your own high-level language (we’d suggest Forth). There is, however, a simple operating system, MTOS.
This is clearly made for use in a classroom, and we’d love to teach a class around a computer like this. The whole thing reminds us of a 16-bit computer like the PDP-11 where everything is a two-byte word. There are only 4K bytes of memory (so 2K words). However, you can accomplish a great deal in that limited space. Thanks to the MTOS API, you don’t have to worry about writing text to the screen and other trivia.
It looks like fun. Let us know what you’ll use it for. If you want to go down a level, try CARDIAC. Or skip ahead a little, and teach kids QBasic.
Today, creating a ground-breaking video game is akin to making a movie. You need a story, graphic artists, music, and more. But until the middle of the 20th century, there were no video games. While several games can claim to be the “first” electronic or video game, one is cemented in our collective memory as the first one we’d heard of: Pong.
The truth is, Pong wasn’t the first video game. We suspect that many people might have had the idea, but Ralph Baer is most associated with inventing a practical video game. As a young engineer in 1951, he tried to convince his company to invest in games that you could play on your TV set. They didn’t like the idea, but Ralph would remember the concept and act on it over a decade later.
But was it really the first time anyone had thought of it? Perhaps not. Thomas Goldsmith Jr. and Estle Ray Mann filed a patent in 1947 for a game that simulated launching missiles at targets with an oscilloscope display. The box took eight tubes and, being an oscilloscope, was a vector graphic device. The targets were physical dots on a screen overlay. These “amusement devices” were very expensive, and they only produced handmade prototypes.
After more than forty years, everyone knows that it’s time to retire the X Window System – X11 for short – on account of it being old and decrepit. Or at least that’s what the common narrative is, because if you dig into the chatter surrounding the ongoing transition there are some real issues that people have with the 16-year old spring chicken – called Wayland – that’s supposed to replace it.
Recently [Brodie Robertson] did some polling and soliciting commentary from the community, breaking down the results from over 1,150 comments to the YouTube community post alone.
The issues range from the expected, such as applications that haven’t been ported yet from X11 to Wayland, to compatibility issues – such as failing drag and drop – when running X11 and Wayland applications side by side. Things get worse when support for older hardware, like GeForce GT610 and GT710 GPUs, and increased resource usage by Wayland are considered.
From there it continues with the lack of global hotkeys in Wayland, graphics tablet support issues, OBS not supporting embedded browser windows, Japanese and other foreign as well as onscreen keyboard support issues that are somehow worse than on X11, no support for overscanning monitors or multiple mouse cursors, no multi-monitor fullscreen option, regressions with accessibility, inability of applications to set their (previously saved) window position, no real automation alternative for xdotool, lacking BSD support and worse input latency with gaming.
Some users also simply say that they do not care about Wayland either way as it offers no new features they want. Finally [Brodie] raises the issue of the Wayland developers not simply following standards set by the Windows and MacOS desktops, something which among other issues has been a point of hotly debated contention for years.
Even if Wayland does end up succeeding X11, the one point that many people seem to agree on is that just because X11 is pretty terrible right now, this doesn’t automatically make Wayland the better option. Maybe in hindsight Mir was the better choice we had before it pivoted to Wayland.
Continue reading “Wayland Will Never Be Ready For Every X11 User” →
When it comes to getting retro hardware running again, there are many approaches. On one hand, the easiest path could be to emulate the hardware on something modern, using nothing but software to bring it back to life. On the other, many prefer to restore the original hardware itself and make sure everything is exactly as it was when it was new. A middle way exists, though, thanks to the widespread adoption of FPGAs which allow for programmable hardware emulation and [Jo] has come up with a new implementation of the Commodore 64 by taking this path.
The project is called the VIC64-T9K and is meant as a proof-of-concept that can run the Commodore 64’s VIC-II video chip alongside a 6502 CPU on the inexpensive Tang Nano 9k FPGA. Taking inspiration from the C64_MiSTer project, another FPGA implementation of the C64 based on the DE10-Nano FPGA, it doesn’t implement everything an original Commodore system would have had, but it does provide most of the core hardware needed to run a system. The project supports HDMI video with a custom kernel, and [Jo] has used it to get a few demos running including sprite animations.
Built with a mix of Verilog and VHDL, it was designed as a learning tool for [Jo] to experiment with the retro hardware, and also brings a more affordable FPGA board to the table for Commodore enthusiasts. If you’re in the market for something with more of the original look and feel of the Commodore 64, though, this project uses the original case and keyboard while still using an FPGA recreation for the core of the computer.
