Author: Al Williams

3809 Articles

Adding Texture To 3D Prints

June 20, 2024 by 20 Comments

[3DJake] likes putting textures on 3D prints using things like patterned build plates and fuzzy skin. However, both of those techniques have limitations. The build plate only lets you texture the bottom, and the fuzzy skin texture isn’t easy to control. So he shows how to use Blender to create specific textures to produce things like wood-like or leather-like surfaces, for example. You can see how it works in the video below.

As [Jake] points out, you might be able to use other artistic programs to do this, but the kind of things we use like FreeCAD of Fusion360 aren’t going to cut it.

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Arduino + TFT = Micro Star Chart

June 20, 2024 by 9 Comments

We always look at the round LCDs and wonder what to do with them other than, of course, a clock. Well, [shabaz] had a great idea: use it as a star map display. The project combines the Arduino, a round TFT, a GPS receiver, and some external flash memory to store data. You can get by without the GPS receiver or flash memory, but you’ll lose features if you do.

We like how he approached the problem. The project contains four major parts and he developed each part independently before integrating them into a whole. The four parts are: reading the GPS, driving the LCD, providing storage for star data, and determining the position of stars. The heavy lifting is done using some public domain code ported over. This code derives from a book called Astronomical Algorithms and uses the Yale Bright Star Catalog database.

The post mentions that the screen might well be a larger rectangular screen and we agree that would make this more usable. Now if you could cram it all into a watch, that might be different. If you want to play with the code, you can actually run the core on Linux. You’ll have to settle for a PNG output of the night sky, but that would be handy for debugging.

We have seen a star chart in a watch before. While this is more a star chart than a planetarium, we have no doubt the early planetarium builders would be suitably impressed.

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Ask Hackaday: How Do You Make Front Panels?

June 20, 2024 by 49 Comments

We’ll admit it. The closer a project is to completion, the less enthusiasm we have for it. Once the main design is clearly going to work on a breadboard, we’re ready to move on to the next one. We don’t mind the PCB layout, especially with modern tools. However, once the board is done, you have to do the case. Paradoxically, this was easier in the old days because you just picked some stock box, drilled some holes, and while it looked terrible, it was relatively easy.

Today, the bar is much higher. You’ll probably 3D print or laser cut an enclosure. If it looks no better than what you did in the 1970s, you won’t win many admirers. We routinely cover projects that could easily pass for commercial products. So how do you do it?

The Parts

The enclosure may even be the easy part. There are plenty of scripts and generators that will make you a nice box that meets your specifications. You can probably even get the holes made as you build. Back in the day, it was a challenge to cut odd-shaped holes for things like serial port connectors. Now, no problem. The printer or laser will just make a hole with any shape you like. You may even want to try a new angle on 3D printing.

Mounting the PCB isn’t that hard, either. With 3D printing, you can create standoffs, but even if you laser cut, you can easily use conventional standoffs. In a pinch, we’ve used long bolts with nuts.

The real problem, it seems to us, is the front panel. Only Star Trek can get away with front panels containing a bunch of knobs and dials with no markings. And although we call them “front” panels, sometimes you need markings on the back or even the sides, too. Continue reading “Ask Hackaday: How Do You Make Front Panels?” →

What You Can See With A SEM?

June 19, 2024 by 4 Comments

The last time we used a scanning electron microscope (a SEM), it looked like something from a bad 1950s science fiction movie. These days SEMs, like the one at the IBM research center, look like computers with a big tank poised nearby. Interestingly, the SEM is so sensitive that it has to be in a quiet room to prevent sound from interfering with images.

As a demo of the machine’s impressive capability, [John Ott] loads two US pennies, one facing up and one face down. [John] notes that Lincoln appears on both sides of the penny and then proves the assertion correct using moderate magnification under the electron beam.

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Linux Fu: Kernel Modules Have Privileges

June 19, 2024 by 13 Comments

I did something recently I haven’t done in a long time: I recompiled the Linux kernel. There was a time when this was a common occurrence. You might want a feature that the default kernel didn’t support, or you might have an odd piece of hardware. But these days, in almost all the cases where you need something like this, you’ll use loadable kernel modules (LKM) instead. These are modules that the kernel can load and unload at run time, which means you can add that new device or strange file system without having to rebuild or even restart the kernel.

Normally, when you write programs for Linux, they don’t have any special permissions. You typically can’t do direct port I/O, for example, or arbitrarily access memory. The kernel, however, including modules, has no such restriction. That can make debugging modules tricky because you can easily bring the system to its knees. If possible, you might think about developing on a virtual machine until you have what you want. That way, an errant module just brings down your virtual machine. Continue reading “Linux Fu: Kernel Modules Have Privileges” →

Lindroid Promises True Linux On Android

June 18, 2024 by 16 Comments

Since Android uses Linux, you’d think it would be easier to run Linux apps on your Android phone or tablet. There are some solutions out there, but the experience is usually less than stellar. A new player, Lindroid, claims to provide real Linux distributions with hardware-accelerated Wayland on phones. How capable is it? The suggested window manager is KDE’s KWIN. That software is fairly difficult to run on anything but a full-blown system with dbus, hardware accelerations, and similar features.

There are, however, a few problems. First, you need a rooted phone, which isn’t totally surprising. Second, there are no clear instructions yet about how to install the software. The bulk of the information available is on an X thread. You can go about 4 hours into the very long video below to see a slide presentation about Lindroid.

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TDK Claims Solid State Battery With 100X Energy Density

June 18, 2024 by 49 Comments

Regulations surrounding disposable batteries have accelerated a quiet race to replace coin cells, which on the whole are not readily rechargeable. TDK produces solid-state batteries and has announced a new material that claims an energy density of about 100 times that of their conventional batteries.

Energy density measures how much energy a system contains relative to its volume. The new battery has 1000 Wh/L. For comparison, old nickel-cadmium cells had about 150 Wh/L. A typical lithium-ion battery usually turns in about 200 – 250 Wh/L.

There aren’t many technical details, but a few things caught our interest. For one, it uses an oxide-based solid electrolyte and lithium alloy anodes. However, what really caught our eye was that it is “intended for use in wearables… that come in direct contact with the human body.” We don’t know if that means the material is safe for your skin or if it depends on being next to your body to operate.

While the energy density is high, keep in mind that the batteries of this type are usually tiny, so the total actual power available is probably not very high. Tiny batteries are definitely a thing. We are always hearing about breakthroughs, but we always wonder if and when we’ll see actual products.