Day: November 23, 2019

Dambusting, R/C Style

November 23, 2019 by 22 Comments

Disclaimer: no dams were actually busted in the making of the video below. But that doesn’t mean that a scale-model homage to the WWII Dam Busters and their “Bouncing Bombs” isn’t worth doing, of course.

In a war filled with hacks, [Barnes Wallis]’ Bouncing Bomb concept might just be the hackiest. In the video below, [Tom Stanton] explains that [Wallis] came up with the idea of skipping a bomb across the surface of a lake to destroy enemy infrastructure after skipping marbles across the water. Using barrel-shaped bombs, he built a rig that could give them the proper amount of backspin and release them at just the right time, letting them skip across the surface of the lake while the bomber made an escape. Upon hitting the rim of the dam, the bomb would sink to explode near the base, maximizing damage.

[Tom]’s scale rig ended up being a clever design with spring-loaded arms to release a 3D-printed barrel after being spun up by a brushless motor. He teamed up with R/C builder [James Whomsley], who came up with a wonderful foam-board Lancaster bomber, just like RAF No. 617 Squadron used. With a calm day and smooth water on the lake they chose for testing, the R/C Lanc made a few test runs before releasing the first barrel bomb. The first run was a bit too steep, causing the bomb to just dive into the water without skipping. Technical problems and a crash landing foiled the second run, but the third run was perfect – the bomb skipped thrice while the plane banked gracefully away. [Tom] also tried a heavy-lift quadcopter run with the bomb rig, something [Barnes Wallis] couldn’t even have dreamed of back in the day.

Hats off to [Tom] and [James] for collaborating on this and getting the skipping to work. It reminds us a bit of the engineered approach to rock-skipping, though with less deadly intentions.

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Hacking Surgery: Suspended Animation May Be Here

November 23, 2019 by 25 Comments

Suspended animation is a staple of science fiction. Need to take a 200 year trip to another star system? Go to sleep in some sort of high-tech coccoon and wake up at your destination. We saw it in Star Trek, 2001, and many other places. Doctors at the University of Maryland have reprtedly put at least one patient in suspended animation, and it isn’t to send them to outer space. The paper (behind a paywall, of course) is available if you have the medical background to wade through it. There’s also a patent that describes the procedure.

Trauma surgeons are frustrated because they often see patients who have been in an accident or have been shot or stabbed that they could save if they only had the time. A patient arriving at an ER with over half their blood lost and their heart stopped have a less than 5% chance of leaving the ER without a toe tag. By placing the patient in suspended animation, doctors can gain up to two hours to work on injuries that previously had to be repaired in mere minutes.

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A 3D Printer Scratch Built For Your Viewing Pleasure

November 23, 2019 by 14 Comments

Today it’s almost always cheaper to buy an imported 3D printer kit than it is to source your own parts and build one yourself. But that doesn’t stop people from doing it anyway. Whether they’re looking for something a bit more solid, or just want to do things their own way, there are still valid reasons to design and build your own machine. Luckily for us in the audience, [Rob Mech] decided to document the build of his custom “LayerFused C201” printer on his YouTube Channel.

If you’ve ever dreamed of taking the plunge and building a 3D printer exactly the way you want, but were never able to manage the time, this seven video series might be the next best thing. Each video takes you through a different step of the construction, from building the frame out of aluminum extrusion all the way to wiring up the endstop switches and the 32-bit SKR v1.3 controller. There’s even a video that introduces the viewer to the concept of a “Frankenstein” printer that uses cobbled together parts just long enough to produce its own final components.

All told, [Rob] says the Bill of Materials for the LayerFused C201 comes to at least $200, but that’s going to take shopping around for the lowest possible prices and potentially even salvaging some components from other machines and projects. Like we said, building a cheap printer is absolutely not the goal here; it’s all about building a printer you want to use. Continue reading “A 3D Printer Scratch Built For Your Viewing Pleasure” →

If You Need A Measurement Tool Just Build A Measurement Tool

November 23, 2019 by 14 Comments

[Darlan Johnson] was working on a wearable project and needed a way to measure the change in voltage and current over time. 

Most measurement tools are designed to take snapshots of a system’s state in a very small window of time, but there are few common ones designed to observe and log longer periods. It’s an interesting point, for example, many power supply related failures such as resets occur sporadically. Longer timescale measuring devices could pick these up.

[Darlan] had a ton of Feathers and shields lying around, and combined them into the needed instrument. An INA219 current sensor records the measurements. They are then displayed on a TFT and logged to an SD card. Everything is bundled into a neat 3D printed case along with a battery for wireless operation. A set of barrel connectors provide the breakout to split the wires for the current measurement.

It’s a neatly done hack and we can see it as a nice addition to any hacker’s measurement drawer.

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New Part Day: The Bizen Transistor

November 23, 2019 by 64 Comments

If we had a dollar for every exciting new device that’s promised to change everything but we never hear of beyond the initial hoopla, we’d own our own private islands in the sun from the beaches of which we’d pick out Hackaday stories with diamond-encrusted keyboards. The electronic engineering press likes to talk about new developments, and research scientists like a bit of publicity to help them win their next grant.

The Bizen transistor however sounds as though it might have some promise. It’s a novel device which resembles a bipolar transistor in which the junctions exhibit Zener diode-like properties, and in which the mechanism is through quantum tunneling rather than more conventional means. If this wasn’t enough, its construction is significantly simpler than conventional semiconductors, requiring many fewer support components to make a logic gate than traditional CMOS or TTL, and requires only eight mask steps to manufacture. This means that lead times are slashed, and that the cost of producing devices is much reduced.

The device’s originator has partnered with a semiconductor fab house to offer a service in which custom logic chips can be produced using the new devices in a series of standard building blocks. This is likely to be only of academic interest to the hacker at the moment, however the prospect of this cost reducing as the technology matures does show promise of reaching the means of some more well-funded hacker projects. It will be a while before we can order a chip with the same ease as a PCB, but this makes that prospect seem just a little bit closer.

Thanks [Ken Boak] for the tip.

There’s Life In That Beard Trimmer Yet!

November 23, 2019 by 33 Comments

You just can’t get a decent beard trimmer these days! At least that’s what [Peter Franck] found when his trusty Panasonic finally expired after a couple of decades and a few replacement batteries. The shaver’s PCB contained a mains-powered NiCd charger which had comprehensively released its magic smoke, and the expensive replacement trimmers he bought simply didn’t cut the mustard.

Many people would have given up in despair, but he persevered, and produced a custom replacement board containing a Maxim DS2710 single-sell NiMH charger, and an AA NiMH cell. It fits perfectly into the space vacated by the previous board, and takes its charge through a micro-USB socket on the edge of the PCB.

It’s interesting to note that NiMH-based projects have in recent years become a comparative rarity on these pages compared to ones using Li-ion or Li-poly cells. This is an inevitable progression on cost, size, and power density grounds, but it’s still worth knowing about projects using the older battery chemistry. He remarks that his razor is now future-proofed, but we’d probably have fitted a USB-C conector before making that assertion. Either way, it’s a neat piece of work that has achieved its aim of making an expired razor useful again. We’ve brought you another razor fix in the past, though a much less sophisticated one.

How To 3D Print Your Identical Twin

November 23, 2019 by 10 Comments

It’s possible to have an enjoyable weekend touring a city with a stolen cardboard cutout from some advertising display or other. However, it’s 2019, and 3D printing means you can go so much further. [Simon] of RCLifeOn went so far as to print a lifesized body double of himself, and it’s only slightly creepy! (Video, embedded below.)

The model was sourced from a 3D scan [Simon] had done with commercial hardware. An Optimus P1 industrial-grade 3D printer was used to print the parts, with total printing time being around 200 hours. Adhesive was used to join the various segments together, and the assembly was then sanded and primed, ready for paint.

Unwilling to tackle the task alone, [Simon] enlisted a professional painter to help put the finishing touches on the piece. The end result is impressive, particularly from a distance. [Simon 2.0] was then sent out to the city centre, aiming to raise money from bewildered passers by.

We suspect the market for custom body doubles will only increase as the technology to create them becomes more widespread. If you’ve tackled a similar project, be sure to let us know. Video after the break.

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