Automatic Timelapses, Made Educational And Easy

April 16, 2020 by Donald Papp 2 Comments

Timelapse fragment from an infrared sky camera watching cloud patterns.

There are plenty of ways to create timelapse videos, but [Andy] has an efficient method for ensuring up-to-date ones exist for his infrared sky camera, and he has it running thanks to some well-documented shell scripts on a spare Raspberry Pi. The resulting timelapse video is always available from the web, and always up-to-date for the current day.

The idea is to automatically fetch images from a remote source (in his case, an infrared sky camera) and turn them into a cumulative video that is regularly updated for the day in question. The resulting video file is either served from the same machine, or sent elsewhere. All that’s needed besides a source for the stills are two shell scripts and some common Linux utilities.

Since [Andy] is mainly interested in tracking clouds his system only runs during daylight hours, but it can be easily changed. In fact, [Andy]’s two shell scripts are great project resources, not only because they are easily modified and well documented, but because he doesn’t make assumptions about how well one might know the command line. He also provides tips from experience; for example he has found that a 120 second interval makes for the best timelapses.

[Andy] runs his scripts on an Raspberry Pi 4, but any Linux system will do. For those who might prefer a more embedded approach, the ESP32-CAM can make a great time lapse camera with remarkably little effort.

Accessible Controller Plays Around With Modularity

April 10, 2020 by Kristina Panos 8 Comments

Video games are a great way to have some fun or blow off a little steam when real life becomes laughable. But stock controllers and other inputs are hardly one size fits all. Even if you have no physical issues, they can be too big, too small, or just plain uncomfortable to hold.

[kefcom] wrote in to give us a heads up about a modular, adaptive system he designed for anyone who is unable to operate a PS3, PS4, or PC with a standard controller. The project was inspired by Microsoft’s adaptive XBOX controller and works pretty much the same way — broken-out buttons, joysticks, and other inputs all connect to a hub that unifies them into a controller the console or computer can communicate with. The major difference is that this project is open source and can be realized much more cheaply.

If you want to give this a try, [kefcom]’s project repo has step-by-step instructions for disassembling two types of wireless controllers and converting them into hubs for modular controls. He’s looking for help with design, documentation, and finding reliable suppliers for all the parts, so let him know if you can assist.

Some players need something more accessible than just broken-out buttons and full-size joysticks. Here’s an adaptive controller that uses ridged foam rollers to actuate buttons.

Wheelbarrow Bass Drives A Sound Garden

April 2, 2020 by Kristina Panos 11 Comments

One of the best things about making music is that it’s so easy to do. There are countless ways to make interesting sounds out of nearly anything if you’re willing to experiment a little bit — just ask anyone who has ever made a guitar out of a cigar box and a broom handle.

[Vicious Squid] dug in to the fertile soil of the garden implement world and cultivated a three-string upright bass with a rich, soulful sound from a familiar workhorse — an aluminium wheelbarrow. Much of the build is made from reclaimed wood, like the solid mahogany neck from an old door frame, and a broom handle.

The bass is constructed arch-top style, meaning that the soundboard — the wood on the front with the f-holes — is a flat piece tacked to curved ribs that span the width of the ‘barrow. A broom handle sound post mounted front to back pushes vibrations from the soundboard to the aluminium body. To round out the agricultural aesthetic, [Vicious Squid] strung it with weed-whacker bass strings, which are no doubt inspired by the use of actual trimmer line.

It’s already plenty loud, but [Vicious Squid] added a piezo pickup for wheeling it into the recording studio. Slap your way past the break to hear a little ditty.

Are your instrument-building skills at the sapling stage? Start with something simpler, like a sliding rubber bandolin.

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Reverse Engineering A Ceiling Fan Remote

March 31, 2020 by Rich Hawkes 2 Comments

In the quest to automate everything in your home, you no doubt have things that aren’t made with home automation in mind. Perhaps your window AC unit, or the dimmer in your dining room. [Seb] has several ceiling fans that are controlled by remotes and wanted to connect them to his home automation system. In doing so, [Seb] gives a good overview of how to tackle this problem and how to design a PCB so he doesn’t have a breadboard lying around connected to the guts of his remote control.

There are several things [Seb] needs to figure out in order to connect his fans to Home Assistant, the home automation system he uses: He needs to determine if the circuit in the remote can be powered by 5 or 3.3 V, he needs to connect the circuit to an ESP32 board, and he needs to figure out if he can create a custom PCB that combines the circuit and the ESP32 into one. The video goes through each of these steps and shows the development of each along the way.

There’s a lot of info in the video, so it might need to be slowed down a bit to see all the details. There are some other reverse engineering of home automation gear on the site, here, or, you might want to build your own remote to control your automated devices.

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How To Try Generative Optimization At Home

March 29, 2020 by Donald Papp 29 Comments

Chairs, spokes on a wheel, bridges, and all kinds of other load-bearing objects are designed such that material is only present where it is needed. There’s a process by which the decisions about how much material to put and where is determined by computer, and illustrating this is [Adam Bender]’s short primer on how to use generative optimization in Autodesk’s Fusion 360 (which offers a variety of free licenses) using a wheel as an example.

Things start with a solid object and a definition of the structural loads expected. The computer then simulates the force (or forces) involved, and that simulation can be used to define a part that only has material where it’s really needed. The results can be oddly organic looking, and this process has been used to optimize spacebound equipment where every gram counts.

It’s far from an automated process, but it doesn’t look too difficult to navigate the tools for straightforward designs. [Adam] cautions that one should always be mindful of the method of manufacturing when designing the part’s final form, which is always good advice but especially true when making oddball shapes and curves. To see the short process in action, watch the video embedded below.

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Can Solder Paste Stencils Be 3D Printed? They Can!

March 27, 2020 by Donald Papp 37 Comments

3D printed solder paste stencil, closeup.

[Jan Mrázek]’s success with 3D printing a solder paste stencil is awfully interesting, though he makes it clear that it is only a proof of concept. There are a lot of parts to this hack, so let’s step through them one at a time.

First of all, it turns out that converting a PCB solder paste layer into a 3D model is a bit of a challenge. A tool [Jan] found online didn’t work out, so he turned to OpenSCAD and wrote a script (available on GitHub) which takes two DXF files as input: one for the board outline, and one for the hole pattern. If you’re using KiCad, he has a Python script (also on GitHub) which will export the necessary data.

The result is a 3D model that is like a solder paste mask combined with a raised border to match the board outline, so that the whole thing self-aligns by fitting on top of the PCB. A handy feature, for sure. [Jan] says the model pictured here printed in less than 10 minutes. Workflow-wise, that certainly compares favorably to waiting for a stencil to arrive in the mail. But how do the actual solder-pasting results compare?

3D printed solder stencil on PCB, after applying solder paste.

[Jan] says that the printed stencil had a few defects but it otherwise worked fine for 0.5 mm pitch ICs and 0402 resistors, and the fact that the 3D printed stencil self-registered onto the board was a welcome feature. That being said, it took a lot of work to get such results. [Jan]’s SLA printer is an Elegoo Mars, and he wasn’t able to have it create holes for 0.2 mm x 0.5 mm pads without first modifying his printer for better X/Y accuracy.

In the end, he admits that while a functional DIY solder stencil can be 3D printed in about 10 minutes, it’s not as though professionally-made stencils that give better results are particularly expensive or hard to get. Still, it’s a neat trick that could come in handy. Also, a quick reminder that we stepped through how to make a part in OpenSCAD in the past, which should help folks new to OpenSCAD make sense of [Jan]’s script.

Don’t Scrape Magnet Wire, Do This Instead

March 9, 2020 by Donald Papp 111 Comments

[Tom] doesn’t much like breadboarding. He prefers to wire up prototypes with perfboard and solder point-to-point with enameled magnet wire. That may sound troublesome to some of you, but [Tom] has come up with a few tips to make prototyping with perfboard and magnet wire easier and more effective, and the biggest tip is about how to manage stripping all that magnet wire.

Push the tip of the magnet wire a small distance into the molten solder and hold it there for a few moments. The solder will bubble away the enamel and tin the copper underneath in the process.

Magnet wire is a thin, solid-core conductor that has a clear coating of enamel. This enamel acts as an electrical insulator. The usual way to strip away the enamel and reveal the shiny copper underneath is to scrape it off, but that would get tiresome when working with a lot of connections. [Tom] prefers to “boil it away” with a blob of molten solder on an iron’s tip.

Begin by melting a small amount of solder on the iron, then push the tip of the magnet wire a small distance into the molten solder and hold it there for a few moments. The enamel will bubble away and the solder will tin the copper underneath in the process. The trick is to use fresh solder, and to clean the tip in between applications. You can see him demonstrate this around the 1:00 mark in the video embedded below.

Once the tip of the magnet wire is tinned, it can be soldered as needed. Magnet wire bends well and holds its shape nicely, so routing it and cutting to size isn’t too difficult. [Tom] also suggests a good hands-free PCB holder, and points out that 0603 sized SMT resistors fit nicely between a perfboard’s 0.1″ pads.

Perfboard (and veroboard) have been standbys of prototyping for a long time, but there are still attempts at improving them, usually by allowing one to combine through-hole and surface-mount devices on the same board, but you can see [Tom] demonstrate using magnet wire on plain old perfboard in the video below.

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