New (mis)Use For Lithophanes: Miniature Diorama Backgrounds

What’s better than a well-lit photo of a 3D-printed miniature? A photo of the miniature in a mini diorama, of course. [OrionDeHunter] shows off a clever technique that has something in common with old-timey photo stages and painted backgrounds, and (mis)uses 3D-printed lithophanes to pull it off. What [OrionDeHunter] does is use a curved and painted lithophane as a stand-in for a background, and the results look great!

Lithophanes are intended to be illuminated from behind to show an image, with thin areas showing as lighter and thicker areas darker, but when it comes to high contrast patterned images like brick walls, the same things that make a good lithophane just happen to also make a pretty good 3D model in the normal sense. No 3D scanning or photogrammetry required.

Here is the basic process: instead of creating a 3D model of a brick wall from scratch, [OrionDeHunter] simply converted an image of a brick wall (or stairs) into a curved lithophane with an online tool. The STL model of the lithophane is then 3D printed, painted, and used as a swappable background. When macro shots of the miniatures are taken, the curved background looks just right and allows for some controlled lighting. It’s a neat trick, and well applied in this project. Some sample images demonstrating how it works are just under the break.

Lithophanes were originally made using marble or thin porcelain, but a modern spin has been put on the technique with 3D printing. Enterprising hackers have even discovered ways to add color, too.

3D-Printing Bigger Wind Turbines

Many decades ago, a much younger version of me was in the car with my dad and my brother, cruising down the highway on some errand or another. We were probably all in the front seat, and none of us were wearing seatbelts; those were simpler times. As we passed under an overpass, my dad said, “Do you know why the overpasses on these roads are so high?” Six-year-old me certainly didn’t, but it was clear dad did and had something to say about it, so we just shook our heads and waited for the lesson. “Because that’s how big nuclear missiles are.” He then went into an explanation of how the Interstate Highway System in the USA, then still in its infancy, was designed to make sure the armed forces could move around the country, so overpasses needed to allow trucks with big loads to pass.

It was an interesting lesson at the time, and over the years I’ve continued to be impressed with the foresight and engineering that went into the Interstate system here in the US. It’s far from perfect, of course, and it’s only recently that the specifications for the system have started to put a pinch on things that seem totally unrelated to overpass dimensions — namely, the size and efficiency of wind turbines.

Continue reading “3D-Printing Bigger Wind Turbines”

The Spin Cycle: Washing Machine Motor Converts 10-Speed To E-Bike

The “Spin Cycle” is an amazing electric bicycle built using a motor salvaged from a washing machine; when the puns are this perfect you have to roll with them. [jimminecraftguy’s] creation is one of the most hacked-together yet functional electric vehicle we’ve seen in a long time.

The drive train of this bicycle starts with a brushless DC motor from a washing machine. It has been slightly modified to run on 48 volts, and is installed inside the triangle of the bike’s frame. It has a chain driving the bike’s crank, retaining the original chain and gearing setup (unlike many electric bike hacks that utilize hub motors). The crank has also been specially modified to include a freewheel, a necessary feature so that the motor can operate without spinning the pedals. Everything except the motor has been custom fabricated including the mounts and the electronics.

[jimminecraftguy] reports speeds of 110 kph which is a little crazy for a 20-year-old aluminum frame bike, and we’d guess it’s not street legal in many jurisdictions, but we can’t really find much fault with this build in general based on the amount of innovation required to get this working at all. A few more improvements for the build are in the works, including improved batteries and a cover for the sides to keep the local law enforcement from getting too suspicious. We can’t wait to see the final version. Continue reading “The Spin Cycle: Washing Machine Motor Converts 10-Speed To E-Bike”

Elegant Shoji Lamps From Your 3D Printer

The gorgeous Shoji-style lamps you’re seeing here aren’t made of wood or paper. Beyond the LEDs illuminating them from within, the lamps are completely 3D printed. There aren’t any fasteners or glue holding them together either, as creator [Dheera Venkatraman] used authentic Japanese wood joinery techniques to make their components fit together like a puzzle.

While we’re usually more taken with the electronic components of the projects that get sent our way, we have to admit that in this case, the enclosure is really the star of the show. [Dheera] has included a versatile mounting point where you could put anything from a cheap LED candle to a few WS2812B modules, but otherwise leaves the integration of electronic components as an exercise for the reader.

All of the components were designed in OpenSCAD, which means it should be relatively easy to add your own designs to the list of included panel types. Despite the colorful details, you won’t need a multi-material printer to run them off either. Everything you see here was printed on a Prusa i3 MK3S in PETG. Filament swaps and careful design were used to achieve the multiple colors visible on some of the more intricate panels.

If the timeless style of these Japanese lanterns has caught your eye, you’ll love this beautiful sunrise clock we covered last year.

Your Microcontroller Is Your IDE

What if your microcontroller IDE was running on the microcontroller itself and not hosted on the computer you use to do the programming? The greatest legacy of Arduino in all its forms has arguably been a software one, in that it replaced annoying proprietary development environments with one that installed easily on a range of operating systems, was easy to use, and above all, worked. The next level of portability is to get rid of any specialize computer-side software. [Ronny Neufeld] wrote MicroIDE for ESP32 as an IDE accessible through a web browser, which interestingly is hosted on the target device itself.

Using the IDE is easy enough, install a binary, connect to the ESP with a web browser, start writing MicroPython code. There is a choice of connecting directly to the chip as a hotspot, or connecting via another WiFi network. The interface is looking pretty slick but he’s at pains to remind us that it’s a work in progress. Sadly there is no source code yet as it’s a binary distribution that is free for non-commercial use, we’d hope that an open-source release might one day happen. It’s not for everyone, but the convenience of accessing the same interface from almost any modern device should help attract a healthy community.

This appears to be the first web-based on-chip ESP IDE we’ve shown you. But it’s not the first on-chip coding example, as this BASIC interpreter shows.

[Main image source: Ubahnverleih / CC0]

Live Map Of London Tube Created In PCB And Lights

If you’re a frequent traveler on a public transit system, it can be helpful to know when the trains or buses are arriving and if there are any delays. We might reach for a tablet to mount on the wall, but that relies on keeping the OS, the software, and its library dependancies up to date. For true reliability you’ll need to build directly in hardware, which is exactly what this map of the London tube system uses.

The base map is printed directly on PCB, with LEDs along each of the major routes to indicate the current location of the trains. A few small chips handle the WiFi connection — it appears to our eye to be an ESP8266 — and pulling the information about the trains from the London Underground API (it would be virtually impossible to build everything for this project in hardware). The hardware can be easily reprogrammed, and with the PCB layout this could be adapted for other public transit fairly easily.

Even apart from the philosophical differences on design between hardware and software approaches, we still appreciate the aesthetic of LEDs on PCB. In fact, we’ve seen a whole host of artwork on PCBs ever since the price came down dramatically in the past two decades.

Thanks to [Al] for the tip!

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Hackaday Links: July 5, 2020

Remember all the hubbub over Betelgeuse back in February? For that matter, do you even remember February? If you do, you might recall that the red giant in Orion was steadily dimming, which some took as a portent of an impending supernova. That obviously didn’t happen, but we now seem to have an explanation for the periodic dimming: an enormous dark spot on the star. “Enormous” doesn’t begin to describe this thing, which covers 70% of the face of a star that would extend past Jupiter if it replaced the sun. The dimming was originally thought to be dust being blown off the star as it goes through its death throes, but no evidence could be found for that, while direct observations in the terahertz range showed what amounted to a reduction in surface temperature caused by the enormous star spot. We just think it’s incredibly cool that Betelgeuse is so big that we can actually observe it as a disk rather than a pinpoint of light. At least for now.

F-15c cockpit
F-15a cockpit

If you think you’ve seen some challenging user interfaces, wait till you get a load of the cockpit of an F-15C Eagle. As part of a new series on human interfaces, Ars Technica invited Col. Andrea Themely (USAF-ret.) to give a tour of the fighter she has over 1,100 hours on. Bearing in mind that the Eagle entered service in 1976 and has been continually updated with the latest avionics — compare the video with the steam gauges of the cockpit of an F-15A — its cockpit is still a pretty busy place. As much as possible has been done to reduce pilot load, with controls being grouped by function and the use of color-coding — don’t touch the yellow and black stuff! — and the use of tactile feedback. It’s a fascinating deep dive into a workplace that few of us ever get to see, and we’re looking forward to the rest of the series.

Sad news from Seattle, where the Living Computers: Museum + Labs is closing up shop. The announcement only says they’re closing “for now”, so there’s at least some hope that the museum will be back once the COVID-19 downturn has run its course. We hope they do bounce back; it really was a great museum with a lot of amazing hardware on display. The Vintage Computer Festival PNW was held there in its inaugural year, an event we covered and had high hopes for in the future. We hope for the best for these educational and cultural institutions, but we can’t help but fear a little for their future.

So you suffer a partial amputation of your left hand, leaving you with only your thumb and your palm. That raises an interesting conundrum: you haven’t lost enough to replace the hand with a prosthetic one, but you still don’t have any fingers. That appears to be what happened to Ian Davis, and so he built his own partial prosthetic to replace his fingers. There’s not much backstory on his YouTube channel, but from what we can gather he has gone through several designs, most of which are myomechanical rather than myoelectric. Through a series of complex linkages, he’s able to control not only the opening and closing of the fingers, but also to splay them apart. It’s all in the wrist, as it were — his input gestures all come from flexing and extending his hand relative to his forearm, where the prosthesis is anchored. This results in a pretty powerful grip — much stronger than a myoelectric hand in a head-to-head test. And the coolness factor of his work is just off the scale. We’re looking forward to more from Ian, and hopefully enough background information for a full story on what he has accomplished.