Hackaday editors Elliot Williams and Mike Szczys recap a great week in hardware hacking. There’s perfection in the air as clever 3D-printing turns a button and LED matrix into an aesthetically awesome home automation display. Take a crash course in RF modulation types to use on your next project. Did you know the DB-9 connector is actually a DE-9? Building your own underwater ROV tether isn’t as simple as it sounds. And Elliot found a treasure trove of zero-ohm jumpers in chip packages — what the heck are these things for?
Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!
Just a few years ago, had someone asked you how much a digital camera with WiFi would cost, you probably wouldn’t have said $6. But that’s about how much [Bitluni] paid for an ESP32-CAM. He wanted to try making the little camera do time lapse, and it turns out that’s pretty easy to do.
Of course, the devil is in the details. The camera starts out needing configuration on the USB interface and that enables the set up of Arduino integration and WiFi configuration. Because it stores each frame of the image on an SD card, the board can’t take rapid-fire pictures. [Bitluni] reports a 3-second delay was about the shortest he could manage, but for most purposes, he was using at least ten seconds.
The program has a live preview window to help you set up the shot, but before your recordings start that should be turned off so as not to overload the little processor and the I/O buses. The result is a bunch of JPG images that you can easily convert to a video on a PC if you wish.
This might be a good way to fit a camera on a 3D printer, especially if the time lapse effect was desired. Otherwise, you might sync to a layer change. Now all [bitluni] needs is an orbital rig.
Most displays are looking to play things faster. We’ve got movies at 60 frames per second, and gaming displays that run at 144 fps. But what about moving in the other direction? [Bryan Boyer] wanted to try this out, so he built the VSMP, or Very Slow Movie Player. It’s a neat device that plays back a movie at about 24 fph (frames per hour) on an e-ink display to demonstrate something that [Bryan] calls Slow Seeing, which, he says “helps you see yourself against the smear of time.” A traditional epic-length movie is now going to run you greater than 8,000 hours of viewing.
Artistic considerations aside, it’s an interesting device from a technical point of view. [Bryan] built it from a 7.4-inch e-ink display from Pervasive Displays. The controller is connected to a Raspberry Pi Zero, which is running a Python script to convert a frame of the movie file into a dithered file, then send it to the display. Because the Pi Zero isn’t a very fast computer, this takes some time, and thus the slow speed of the VSMP. Originally, [Bryan] had set it up to run as fast as the system could manage, which was about 25 seconds per frame, or about 2 frames per minute. He decided to slow it down a bit further to the more attractive multiple of 24 frames per hour to contrast with the 24 frames per second of the original movie. He did this by using a CRON job that kicks of the conversion script once every 2.5 minutes and increments the frame counter. All of this is topped off with a nice 3D-printed case that has a lovely interference pattern to make a rather neat and intriguing project.
Perhaps the best part of this is see a time-lapse of the VSMP — life moves quickly around it while 2001: A Space Odyssey plays at normal speed.
Camera sliders are a fantastic tool for those who wish to shoot beautiful and smooth panning video, or take expressive time-lapse shots. They can also be remarkably expensive, which creates an incentive for the DIYer to innovate at home. [Richard] wanted a motorized slider and didn’t want to break the bank, and thus, a build was born.
Starting with an existing non-motorized camera slider makes things easier, though there’s no reason [Richard]’s techniques couldn’t be applied to a completely DIY build. A NEMA stepper motor is fitted to the frame, and connected to the camera shuttle with a toothed belt. The stepper is controlled by an Arduino, which allows for both timelapse and smooth panning modes, and can be controlled with an IR remote sourced from Amazon. The slider is also interfaced with a Processing sketch, which gives a graphical representation of the slider’s current position on the laptop’s screen, which helps for setting up a shot.
Most time-lapse videos of 3D prints show a steadily growing print with a crazy blur of machine movement everywhere else. This is because an image is captured at a regular time interval, regardless of what’s physically going on with the machine. But what if images were captured at consistent machine positions instead? [FormerLurker]’s Octolapse plugin for OctoPrint came out of beta recently and does exactly that, and the results are striking. Because OctoPrint knows where a 3D printer’s print head is at all times, it’s possible for a plugin to use this information to create time-lapse videos where the print head position is consistent instead of a crazy blur, or even have the print head absent from the shot altogether.
[FormerLurker] had originally created stabilized time lapses by hand editing G-code, which had great results but was inefficient and time-consuming. This plugin is the result of his work at automating and enhancing the process, and is also his first serious open source programming project. We’ve covered upgrading a 3D printer with OctoPrint before, and the plugins functionality of OctoPrint means features can be added independently from the core system, which itself largely remains a one-woman effort by creator and maintainer [Gina Häußge].
Thanks to the holiday gifting cycle, many homes are newly adorned with 3D printers. Some noobs are clearly in the “plug and play” camp, looking for a user experience no more complicated than installing a new 2D printer. But most of us quickly learn that adding a dimension increases the level of difficulty substantially, and tinkering ensues.
One such tinkerer, [Marco Reps], has been taking his new Cetus 3D printer to new places, and his latest video offers a trio of tips to enhance the user experience of this bare-bones but capable printer. First tip: adding a heated bed. While the company offers a heated aluminum bed for ABS and PETG printing at a very reasonable price, [Marco] rolled his own. He bolted some power resistors to the aluminum platen, built a simple controller, and used the oversized stock power supply to run everything.
To contain the heat, tip two is an enclosure for the printer. Nothing revolutionary here — [Marco] just built a quick cover from aluminum profiles and acrylic.
But the clear case allows for tip number three, the gem of this video: synchronized time-lapse photography. Unhappy with the jerky time-lapse sequences that are standard fare, he wrote a Python program that uses OpenCV to compare webcam frames and save those that are similar to the last saved frame. This results in super smooth time-lapse sequences that make it look like the print is being extruded as a unit. Pretty neat stuff.
A good time-lapse video can be useful visual documentation, and since [Tommy]’s phone is the best camera he owns he created two simple shell scripts to grab time-lapse images and assemble them into a video. [Tommy]’s work is just the glue between two other things: an app that turns the phone into an IP camera with a web server on the local network, and the ability to grab a still image from that server on demand.
The app he uses for his iPhone normally serves video but has an undocumented feature that allows single frames to be downloaded by adding ‘/photo’ to the end of the URL, but the ability to get a still image is a common feature on IP camera apps for smartphones. His capture script (GitHub repository here) should therefore need only minor changes to work with just about any IP camera app.
Perching a phone over a workspace and using it to create a time-lapse with a couple of shell scripts is a great example of combining simple tools to get better functionality. It could be a good way to get additional use out of an older smartphone, too. Heck, even older dumbphones can still get some use out of them; Shmoocon 2017 brought us details on rolling your own 1G network.