It seems as if everyone has finally decided to stop pretending that standing in front of a desk for 8+ hours was something anyone actually wanted to do, and once again embrace the classic adjustable office chair. But whether you’re writing code in a cubicle or are one of those people who apparently makes a living by having people watch them play video games, one thing is certain: your chair needs to be cool enough to make up for the years shaved off your life by sitting in it all day.
Case in point, these chairs that were made out of seats salvaged from a Porsche 996 by [Colby Newman]. You might never be able to afford the car they came out of on your salary, but at least you can pretend you’re power shifting into fifth while doing your TPS reports.
The first step, and arguably the most important one, was getting the seats from a Porsche. [Colby] wisely cautions the reader that they should avoid seats with air bags, as the last thing you want is your chair to explode while you’re streaming Fortnite. This is especially true if you are looking to salvage the seats yourself from the junkyard, as special care needs to be taken on how you remove them from the vehicle.
Assuming you got the seat without blowing yourself up, the next step is to mate it to the adjustable base. This part is going to depend on the make and model of vehicle you got the seats out of, but in this case it was fairly easy to use some flat steel bars to adapt the tubular frame of the Porsche’s seat to the base from the donor office chair. [Colby] put everything together with nuts and bolts, but this could potentially be an excuse to drag out the welder.
We’ve previously seen the driver seat salvaged from a wrecked car for use in a simulator, and a standard office chair upgraded with force feedback. We wonder who will be the first to combine all these ideas into one ultimate office racing chair…
Once relegated to the proverbial Linux loving Firefox user, ad blocking has moved into public view among increased awareness of privacy and the mechanisms of advertising on the internet. At the annual family gathering, when That Relative asks how to setup their new laptop, we struggle through a dissertation on the value of ad blockers and convince them to install one. But what about mediums besides the internet? Decades ago Tivo gave us one button to jump through recorded TV. How about the radio? If available, satellite radio may be free of The Hated Advertisement. But terrestrial radio and online streams? [tomek] wasn’t satisfied with an otherwise sublime experience listening streaming Polish Radio Three and decided to build a desktop tool to detect and elide ads from the live audio stream.
[tomek] was aware of this hip knowledge domain called Digital Signal Processing but hadn’t done any of it themselves. Like many algorithmic problems the first step was to figure out the fastest way to bolt together a prototype to prove a given technique worked. We were as surprised as [tomek] by how simple this turned out to be. Fundamentally it required a single function – cross-correlation – to measure the similarity of two data samples (audio files in this case). And it turns out that Octave provides it in the box. After snipping the start-of-ad jingle out of a sample file and comparing it to a radio program [tomek] got the graph at the left. The conspicuous spike is the location of the jingle in the audio file.
At this point all that was left was packaging it all into a one click tool to listen to the radio without loading an entire analysis package. Conveniently Octave is open source software, so [tomek] was able to dig through its sources until they found the bones of the critical xcorr() function. [tomek] adapted their code to pour the audio into a circular buffer in order to use an existing Java FFT library, and the magic was done. Piping the stream out of ffmpeg and into the ad detector yielded events when the given ad jingle samples were detected.
[tomek] packaged that tool into a standalone executable, but the gem here is the followup post. After removing ads in the online stream they adapted a RaspberryPi to listen to an FM receiver and remote control their Yamaha tuner over the network. So when the tuner is playing Radio Three the Pi notices and ducks the audio appropriately to avoid those pesky ads. Video of this after the break.
Continue reading “Cross-Correlation Makes Quick Work Of Ads”
No matter how far modern computer hardware advances, there’s still a fairly large group of people who yearn for the early days of desktop computing. There’s something undeniably appealing about these early systems, and while even the most hardcore vintage computer aficionado probably wouldn’t be using one as their daily computer anymore, it’s nice to be able to revisit them occasionally. Of course the downside of working with computers that may well be older than their operators is that they are often fragile, and replacement parts are not necessarily easy to come by.
But thanks to projects like this impressive ATX Amiga 4000 motherboard shown off by [hese] on the Amibay forums, getting first hand experience with classic computing doesn’t necessarily mean relying on vintage hardware. By making an Amiga that’s compatible with standard ATX computer cases and power supplies, it becomes a bit more practical to relive the Commodore glory days. Right now it’s mainly a personal project, but if there’s sufficient interest it sounds as if that might change.
This board could be considered a modern reincarnation of the Amiga 4000T, which was an official tower version of the standard Amiga 4000 released by Commodore in 1994. It features a 68030 CPU, with 16 MB Fast RAM and 2 MB Chip RAM. For expansion there are four full-length Zorro III slots and three ISA slots, as well as IDE ports for a floppy and hard drive.
The board really looks the part of a professionally manufactured computer motherboard from the late 1990s, which speaks not only to the attention to detail [hese] put into its design, but the manufacturing capabilities that are now available to the individual. With passionate people like this involved, it’s hardly surprising that the vintage computer scene is so vibrant.
Of course, this isn’t the first newly built “vintage” computer we’ve seen here at Hackaday. From bare-minimum 8085 computers to the comparative luxury of the 6502-powered Cactus, it seems like what’s old is new again.
[Thanks to Laurens for the tip.]
Water rockets are one of the most fun and exciting science-adjacent activities one can take part in during the summer, and are popular with children and adults alike. Designs range from a bike pump with a cork in a bottle, up to significantly more advanced hardware. [Air.command]’s two-stage water rocket definitely fits into the latter category.
The build is initially somewhat confronting in its complexity, but after a thorough read-through the operating principles become clear. It’s an all-mechanical setup which relies on the weight of the upper stage and the initial acceleration of the rocket to keep the two stages coupled. It’s only when the first stage stops delivering thrust that a spring forces the two stages apart, and the upper stage rockets ever higher.
Parts-wise, everything is fairly accessible – with pieces cribbed from garden hose fittings, retractable pens and other household ephemera. It’s not the easiest thing to put together, but with perseverance and some tweaking and tuning, it’s definitely achievable for the home gamer, with no advanced tools or techniques required.
Now that you’ve got a two-stage rocket under construction, you might want to consider upgrading your launchpad. Video after the break.
Continue reading “Build Your Own Two-Stage Water Rockets”
Ah, Nixie tubes. You’re not cool unless you have a few Nixie tubes sitting around, and you’re not awesome unless you’ve built your own Nixie tube clock. That’s what [Thomas] is doing for his entry into the Hackaday Prize, and he’s come up with a very low-cost way of doing it.
For the high voltage supply of this build, [Thomas] is turning to one of the standard circuits based on the MC34063 that’s simple enough and good enough to make everything work. There are really no surprises with the power supply here. This is all a project about turning on different digits inside the Nixie, though, and for that [Thomas] spun his own board capable of driving a pair of IN-1 Nixies with a single ATMega8.
These two-Nixie boards are daisy chained together through a UART connection, where each board passes digits down the line. For example, the first board receives, 12, 30, and 59, displays 59, and passes 12 and 30 down to the next boards. The second board then displays 30 and passes 12 to the last board.
Of course, if you’ve designed a Nixie driver, the next thing to do is to build a clock. [Thomas] had the rather clever idea of making an enclosure for this clock out of concrete, using a 3D printed interior mold. Everything seemed to be going well until it was time to pull the interior mold out, and a few light taps resulted in some fairly large cracks. That’s disappointing, but with a slight redesign and some more fibers in the concrete mix, this is going to turn out to be a weighty win.
I’ve always appreciated simulation tools. Sure, there’s no substitute for actually building a circuit but it sure is handy if you can fix a lot of easy problems before you start soldering and making PCBs. I’ve done quite a few posts on LTSpice and I’m also a big fan of the Falstad simulator in the browser. However, both of those don’t do a lot for you if a microcontroller is a major part of your design. I recently found an open source project called Simulide that has a few issues but does a credible job of mixed simulation. It allows you to simulate analog circuits, LCDs, stepper and servo motors and can include programmable PIC or AVR (including Arduino) processors in your simulation.
The software is available for Windows or Linux and the AVR/Arduino emulation is built in. For the PIC on Linux, you need an external software simulator that you can easily install. This is provided with the Windows version. You can see one of several videos available about an older release of the tool below. There is also a window that can compile your Arduino code and even debug it, although that almost always crashed for me after a few minutes of working. As you can see in the image above, though, it is capable of running some pretty serious Arduino code as long as you aren’t debugging.
Continue reading “Simulate PIC and Arduino/AVR Designs with no Cloud”
Quite often we see applications of hacking and DIY in the medical field. From 3D printed prosthetics to hacked insulin pumps, there’s a wide variety of stuff you can do, but what about psychology? That’s what our Hack Chat this Friday is all about.
Our guest for this week’s Hack Chat is Curt White. He’s been building medical devices for years, and when he’s not doing that he’s creating interactive installation art and costumes. At work he’s a device and sensor developer at the Child mind Institute MATTER Lab where he designs and researches wearable medical devices for children with mental health issues. He’s currently working on gesture detection using wearables, machine learning optimized for microcontrollers, and building and fixing prototypes.
For this hack chat, we’ll talk about how mental health can be addressed by building things with a focus on wearable devices and sensor data. How are wearables challenging the outdated and arbitrary classification of psychiatric disorders, and what is the potential for audio, EEG, and fMRI to help us progress beyond checklist diagnosis? We’ll also talk about:
- Hacking for mental health
- Addressing the intangible with the tangible
- Working with medical researchers
- The fact that you don’t need an IRB if you don’t accept federal funding, or are working in Belize.
You are, of course, encouraged to add your own questions to the discussion. You can do that by leaving a comment on the Hacking For Mental Health Event Page and we’ll put that in the queue for the Hack Chat discussion.
Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week is just like any other, and we’ll be gathering ’round our video terminals at noon, Pacific, on Friday, August 24th. Need a countdown timer? Go go go
Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io.
You don’t have to wait until Friday; join whenever you want and you can see what the community is talking about.