Laser And Webcam Team Up For Micron-Resolution Flatness Measurements

March 16, 2023 by 36 Comments

When you want to measure the length, breadth, or depth of an object, there are plenty of instruments for the job. You can start with a tape measure, move up to calipers if you need more precision, or maybe even a micrometer if it’s a really critical dimension. But what if you want to know how flat something is? Is there something other than a straightedge and an eyeball for assessing the flatness of a surface?

As it turns out, there is: a $15 webcam and a cheap laser level will do the job, along with some homebrew software and a little bit of patience. At least that’s what [Bryan Howard] came up with to help him assess the flatness of the gantry he fabricated for a large CNC machine he’s working on.

The gantry arm is built from steel tubing, a commodity product with plenty of dimensional variability. To measure the microscopic hills and valleys over the length of the beam, [Bryan] mounted a lens-less webcam to a block of metal. A cheap laser level is set up to skim over the top of the beam and shine across the camera’s image sensor.

On a laptop, images of the beam are converted into an intensity profile whose peak is located by a Gaussian curve fit. The location of the peak on the sensor is recorded at various points along the surface, leading to a map of the microscopic hills and valleys along the beam.

As seen in the video after the break, [Bryan]’s results from such a quick-and-dirty setup are impressive. Despite some wobblies in the laser beam thanks to its auto-leveling mechanism, he was able to scan the entire length of the beam, which looks like it’s more than a meter long, and measure the flatness with a resolution of a couple of microns. Spoiler alert: the beam needs some work. But now [Bryan] knows just where to scrape and shim the surface and by how much, which is a whole lot better than guessing.   Continue reading “Laser And Webcam Team Up For Micron-Resolution Flatness Measurements” →

Wooden ITX PC Case Smacks Of Sophistication

March 16, 2023 by 15 Comments

Computer cases have come a long way from the ugly beige boxes of the early 2000s. Still, if it was going to sit on his desk, [MXC Builds] wanted something with a little more class. His custom Ironbark ITX PC seems to fit the aesthetic nicely.

The case’s outer shell is ironbark wood cut at 45 degrees and joined for a beautiful waterfall edge (the wood grain seems to flow uninterrupted). The power supply was heavily modified to take a thinner but larger fan, and a new cover and intake grill were 3D printed. As there were no mounting holes on the bottom of the power supply, he printed a bracket with spring clips to hold the PSU securely. Next, he routed a PCI riser cable to the other side of the internal panel so the GPU could mount on the back. He cut custom cables to match up the lengths needed for every run. Finally, rather than placing the power button on the front or top, it was on the side in a custom bracket.

It’s an absolutely gorgeous build that packs some respectable hardware in a tiny space (7.9 L or ~482 in3). The use of 3D printed parts and careful planning results in an incredibly tidy computer that most would proudly display on their desk. It is an open-air case, and if you’re looking for something a little more enclosed, perhaps this mid-century PC might whet your appetite.

Continue reading “Wooden ITX PC Case Smacks Of Sophistication” →

Raspberry Pi Adds Second Laptop Monitor

March 15, 2023 by 17 Comments

If you have a cheap laptop and you realize you can’t connect a second monitor to it, what do you do? Well, if you are [Pierre Couy], you grab a Raspberry Pi and put together a virtual screen solution.

Like all good projects, this one started with some goals and requirements:

  • Low latency
  • Redable text
  • At least 10 frames per second
  • Fast catch up if the remote screen falls behind
  • Low-bitrate encoding; no hardware acceleration
  • A DHCP server on the Pi to manage the network
  • Power control for the attached monitor

Continue reading “Raspberry Pi Adds Second Laptop Monitor” →

Sixteen wires of various colors are attached in pairs to record the electrical activity of split gill fungi (Schizophyllum commune) on a mossy, wooden stick. photo by Irina Petrova Adamatzky

Unconventional Computing Laboratory Grows Its Own Electronics

March 15, 2023 by 6 Comments

While some might say we’re living in a cyberpunk future already, one technology that’s conspicuously absent is wetware. The Unconventional Computing Laboratory is working to change that.

Previous work with slime molds has shown useful for spatial and network optimization, but mycelial networks add the feature of electrical spikes similar to those found in neurons, opening up the possibility of digital computing applications. While the work is still in its early stages, the researchers have already shown how to create logic gates with these fantastic fungi.

Long-term, lead researcher [Andrew Adamatzky] says, “We can say I’m planning to make a brain from mushrooms.” That goal is quite awhile away, but using wetware to build low power, self-repairing fungi devices of lower complexity seems like it might not be too far away. We think this might be applicable to environmental sensing applications since biological systems are likely to be sensitive to many of the same contaminants we humans care about.

We’ve seen a other efforts in myceliotronics, including biodegradable PCB substrates and attempts to send sensor signals through a mycelial network.

Via Tom’s Hardware.

E-Paper Wall Paper

March 15, 2023 by 7 Comments

Just like the clock clock of old, there’s something magical about a giant wall of smaller pieces working together to make a larger version of that thing. The E-Paper Wall 2.0 by [Aaron Christophel] is no exception as it has now upgraded from 2.9″ to 7.4″ screens.

On the 1.0 version, the bezels made it harder to make out the image. The larger screens still have bezels but the larger screen area makes it much easier to make out the image. 3D-printed clips hold the displays onto a plywood backer. We can marvel that e-ink price tags brought the price of e-ink down so that building a wall is still expensive but not eye-wateringly so. The 5×9 array likely uses a module sold on DigiKey for $47 each.

So aside from being willing to drop some money on a custom piece of art, what’s special about this? The real magic comes with the firmware and tooling that [Aaron] developed to flash custom firmware onto each of the 45 displays. A 100MHz ZBS243/SEM9110 8051-based controller lives inside each display and [Aaron] even has a Ghidra plugin to reverse-engineer the existing firmware. It only has 64kb of flash onboard, so [Aaron] devised a clever compression technique that enabled him to store complex images on the displays. A 3D-printed jig with pogo pins means flashing them doesn’t require soldering pins or headers, just drop it on and flash it with an Arduino with a helpful library [Aaron] wrote. A central station communicates with the various displays over ZigBee to send image updates.

The 8051 has a funny way of showing up in projects like this portable soldering iron or the TV Guardian. In many ways, it is a boon for us hackers as it makes it easier to reverse engineer and write new custom firmware when so many devices use the same architecture.

Continue reading “E-Paper Wall Paper” →

Spin Up To Speed With This Stroboscope

March 15, 2023 by 3 Comments

A stroboscope is not the most common tool, and while they can be purchased fairly inexpensively from various online stores, they are straightforward enough tools that plenty of us could build our own mostly from parts laying around. The basic idea is to shine a flashing light on a spinning object, and when it appears stationary the stroboscope will indicate the rotational speed. There are a few specialty parts that might not be in everyone’s parts drawers, though, and [John] shows us the ins-and-outs of his own DIY stroboscope.

The effect relies on extremely precise timing, and as such the most important part of a build like this is making sure to get the LED circuitry correct so its duty cycle and frequency can be tightly controlled. [John] is using a PT4115E driver board for the LED, and is using it to power a 1W white LED which also includes its own heat sink and lens. The controls for the stroboscope are handled by an ATtiny1614 microcontroller which shows its pulse rate on a small screen. The user can control the rate the LED flashes with simple controls, and when the spinning object appears to come to a stop the only thing left to do is read this value off of the screen.

While it might seem like an overly niche tool, stroboscopes have plenty of day-to-day uses. Older cars that used a central distributor made use of a specialty stroboscope called a timing light in order to properly advance the ignition timing of the engine. They also retain some use in medical applications, and plenty of older readers may be familiar with their use adjusting the speed on record players. They can also be used to make sure the shutter speeds on cameras are calibrated correctly.

Continue reading “Spin Up To Speed With This Stroboscope” →

Voice Without Sound

March 15, 2023 by 14 Comments

Voice recognition is becoming more and more common, but anyone who’s ever used a smart device can attest that they aren’t exactly fool-proof. They can activate seemingly at random, don’t activate when called or, most annoyingly, completely fail to understand the voice commands. Thankfully, researchers from the University of Tokyo are looking to improve the performance of devices like these by attempting to use them without any spoken voice at all.

The project is called SottoVoce and uses an ultrasound imaging probe placed under the user’s jaw to detect internal movements in the speaker’s larynx. The imaging generated from the probe is fed into a series of neural networks, trained with hundreds of speech patterns from the researchers themselves. The neural networks then piece together the likely sounds being made and generate an audio waveform which is played to an unmodified Alexa device. Obviously a few improvements would need to be made to the ultrasonic imaging device to make this usable in real-world situations, but it is interesting from a research perspective nonetheless.

The research paper with all the details is also available (PDF warning). It’s an intriguing approach to improving the performance or quality of voice especially in situations where the voice may be muffled, non-existent, or overlaid with a lot of background noise. Machine learning like this seems to be one of the more powerful tools for improving speech recognition, as we saw with this robot that can walk across town and order food for you using voice commands only.

Continue reading “Voice Without Sound” →