Author: Dan Maloney

3368 Articles

Automate The Freight: The Convenience Store That Comes To Your Door

June 20, 2022 by 45 Comments

For as popular as they became during the COVID-19 lockdowns, grocery delivery services like InstaCart rely on a basic assumption to work: that customers know exactly what they want when they order. Once that hurdle is overcome, the transaction is simple — the driver accepts the job, drives to the store to pick up the order, and takes it to the customer. It requires the use of a fair amount of technology to coordinate everything, but by and large it works, and customers are generally willing to pay for the convenience.

But what if you could cut out that step where the driver goes to pick up your order? What if instead of paying someone to pick and pack your order and bring it to your front step, you just ordered up the whole store instead? That’s the idea behind Robomart, which seeks to deploy a fleet of mobile stores for when the convenience store isn’t quite convenient enough.  And the way the company is choosing to roll out its service, not to mention the business model itself, may hold key lessons for other delivery automation platforms.

Continue reading “Automate The Freight: The Convenience Store That Comes To Your Door” →

Raspberry Pi Simulates The Real Analog TV Experience

June 20, 2022 by 18 Comments

If you’ve laid hands on a retro analog TV, have the restoration bug, and you plan to make the final project at least somewhat period-correct, you face a bit of a conundrum: what are you going to watch? Sure, you can serve up just about any content digitally these days, but some programs just don’t feel right on an old TV. And even if you do get suitably retro programming, streaming isn’t quite the same as the experience of tuning your way through the somewhat meager selections as we did back in the analog days.

But don’t worry — this Raspberry Pi TV simulator can make your streaming experience just like the analog TV experience of yore. It comes to us from [Rodrigo], who found a slightly abused 5″ black-and-white portable TV that was just right for the modification. The battery compartment underneath the set made the perfect place to mount a Pi, which takes care of streaming a variety of old movies and shorts. The position of the original tuning potentiometer is read by an Arduino, which tells the Pi which “channel” you’re currently tuned to.

Composite video is fed from the Pi’s output right into the TV’s video input, and the image quality is just about what you’d expect. But for our money, the thing that really sells this is the use of a relay to switch the TV’s tuner back into the circuit for a short bit between channel changes. This gives a realistic burst of static and snow, just like we endured in the old days. Hats off to [Rodrigo] for capturing everything that was awful about TV back in the day — Mesa of Lost Women, indeed! — but still managing to make it look good.

Continue reading “Raspberry Pi Simulates The Real Analog TV Experience” →

This Arduino Pen Plotter Is Built For Speed

June 19, 2022 by 20 Comments

We see a lot of simple pen plotter projects around here, and while we appreciate them one and all, most of them are a little on the slow side. That’s OK — a glacial pace is sometimes all that’s needed, as long as it gets the job done. But there’s nothing wrong with putting the pedal to the metal, so to speak. And that’s exactly what this super-fast Arduino-based plotter is all about.

As the story goes, [IV Projects] felt the need for speed after building an earlier pen plotter project that worked, but failed to excite. With the additional goal of keeping the plotter easy to build with cheap parts, the design centers on a “grit roller drive” for the Y-axis — the one that actually moves the paper back and forth. And move it does, using Dremel tool sanding drums on a lightweight shaft to maximize acceleration. In fact, all the moving parts are kept as lightweight as possible, and the results really show — the three steppers really sing when this plotter is in action.

There are some really clever details in [IV Projects]’ design. We particularly like the way the pen lift mechanism works, and the surprise appearance of a clothespin spring as a belt tensioner was a real treat. Judging by the pile of rejected prototype parts, it took quite a bit of work to get this design right. If you’d like to build your own, STLs are available for the printed parts.

If you’re interested in what the other end of the speed scale looks like, check out this bare-minimum pen plotter.

Continue reading “This Arduino Pen Plotter Is Built For Speed” →

Hackaday Links Column Banner

Hackaday Links: June 19, 2022

June 19, 2022 by 11 Comments

The James Webb Space Telescope has had a long and sometimes painful journey from its earliest conception to its ultimate arrival at Lagrange point L2 and subsequent commissioning. Except for the buttery-smooth launch and deployment sequence, things rarely went well for the telescope, which suffered just about every imaginable bureaucratic, scientific, and engineering indignity during its development. But now it’s time to see what this thing can do — almost. NASA has announced that July 12 will be “Image Release Day,” which will serve as Webb’s public debut. The relative radio silence from NASA on Webb since the mirror alignment was completed — apart from the recent micrometeoroid collision, of course — suggests the space agency has been busy with “first light” projects. So there’s good reason to hope that the first released images from Webb will be pretty spectacular. The images will drop at 10:30 AM EDT, so mark your calendars and prepare to be wowed. Hopefully.

Continue reading “Hackaday Links: June 19, 2022” →

Balancing A Motor With An Oscilloscope

June 18, 2022 by 17 Comments

With all things in life, one must seek to achieve balance. That may sound a little like New Age woo-woo, but if you think it’s not literally true, just try tolerating a washing machine with a single comforter on spin cycle, or driving a few miles on unbalanced tires.

Anything that rotates can quickly spin itself into shrapnel if it’s not properly balanced, and the DIY power tools in [Matthias Wandel]’s shop are no exception. Recent upgrades to his jointer have left the tool a bit noisy, so he’s exploring machine vibrations with this simple but clever setup. Using nothing but a cheap loudspeaker and an oscilloscope, [Matthias] was able to characterize vibrations in a small squirrel-cage blower — he wisely chose to start small to validate his method before diving into the potentially dangerous jointer. There was quite a lot to be learned from the complex waveforms coming back from the transducer, analysis of which was greatly helped by the scope’s spectrum analyzer function. The video below shows the process of probing various parts of the blower, differentiating spectral peaks due to electrical noise rather than vibration, and actually using the setup to dynamically balance the fan.

We’d rate this as yet another handy shop tip from [Matthias], and we’ll be looking out for the analysis of his jointer. Want to do the same but you don’t have an oscilloscope? No problem — an earbud and Audacity might be all you need.

Continue reading “Balancing A Motor With An Oscilloscope” →

Wooden You Like To Hear A CNC-Cut Phonograph Record?

June 17, 2022 by 22 Comments

Say what you will about [Thomas Edison], but it’s hard to deny the genius of his self-proclaimed personal favorite invention: the phonograph. Capturing sound as physical patterns on a malleable medium was truly revolutionary, and the basic technology that served as the primary medium of recorded sound for more than a century and built several major industries is still alive and kicking today.

With so much technological history behind it, what’s the aspiring inventor to do when the urge to spin your own phonograph records strikes? Easy — cut them from wood with a CNC router. At least that’s how [alnwlsn] rolled after the “one-percent inspiration” hit him while cutting a PCB with his router. Reasoning that the tracks on the copper were probably about as fine as the groove on a record, he came up with some math to describe a fine-pitch spiral groove and overlay data from a sound file, and turn the whole thing into G-code.

For a suitable medium, he turned to the MDF spoil board used to ship PCB stencils, which after about three hours of milling resulted in a rather hairy-looking 78-RPM record. Surprisingly, the record worked fairly well on a wind-up Victrola. The spring-powered motor was a little weak for the heavy wooden record and needed a manual assist, but you can more or less clearly hear the 40-second recording. Even more surprising was how much better the recording sounded when the steel needle was replaced with a chunk of toothpick. You can check out the whole thing in the video below, and you’ll find the G-code generation scripts over on GitHub.

Is all this talk about reproducing music using wiggly lines confusing you? Woah, there, whippersnapper — check out [Jenny]’s primer for the MP3 generation for the background you need.

Continue reading “Wooden You Like To Hear A CNC-Cut Phonograph Record?” →

Laser Brings Autofocus To Tricked-Out Large Format Film Camera

June 17, 2022 by 6 Comments

You can’t argue with the results of large-format film cameras — picture the boxy bellows held by a cigar-chomping big-city press photographer of the 1940s — but they don’t really hold a candle to the usability and portability of even the earliest generations of 35mm cameras. And add in the ease-of-use features of later film and digital cameras, and something like a 4×5 Graflex seems like a real dinosaur.

Or maybe not. [Aleksi Koski] has built a large-format camera with autofocus, the “Conflict 45.” The problem with a lot of the large-format film cameras, which tend to be of a non-reflex optical design, is that it’s difficult or even impossible to see what you’re shooting through the lens. This makes focusing a bit of a guessing game, a problem that [Aleksi] addresses with his design. Sadly, the linked Petapixel article is basically devoid of technical details, but from what we can glean from it and the video below, the Conflict 45 is a 4″x5″ sheet-film camera that has a motorized lens board and a laser rangefinder. A short video has a through-viewfinder view showing an LCD overlay, which means there’s some kind of microcontroller on board as well, which is probably used for the calculations needed to compensate for parallax errors during close focusing, as well as other uses.

The camera is built from 3D printed parts; [Aleksi] says that this is just a prototype and that the finished camera will have a carbon-fiber body. We’d love to see more build details, but for now, we just love the idea of an easy-to-use large-format camera. Just maybe not that big.

Continue reading “Laser Brings Autofocus To Tricked-Out Large Format Film Camera” →