Like most accidents, it happened in an instant that seemed to last an eternity. I had been felling trees for firewood all afternoon, and in the waning light of a cold November day, I was getting ready to call it quits. There was one tiny little white pine sapling left that I wanted to clear, no thicker than my arm. I walked over with my Stihl MS-290, with a brand new, razor sharp chain. I didn’t take this sapling seriously — my first mistake — and cut right through it rather than notching it. The tree fell safely, and I stood up with both hands on the saw. Somehow I lost my footing, swiveled, and struck my left knee hard with the still-running chainsaw. It kicked my knee back so hard that it knocked me to the ground.
In another world, that would likely have a been a fatal injury — I was alone, far from the house, and I would have had mere minutes to improvise a tourniquet before bleeding out. But as fate would have it, I was protected by my chainsaw chaps, full of long strands of the synthetic fiber Kevlar.
The chain ripped open the chaps, pulled the ultrastrong fibers out, and instantly jammed the saw. I walked away feeling very stupid, very lucky, and with not a scratch on me. Although I didn’t realize it at the time, I owed my life to Stephanie Kwolek.
At some point, most of us have learned a little of the ancient art of origami. It’s a fascinating art form, and being able to create a recognizable model by simply folding paper in the right order can be hugely satisfying. Most of us move on to other pursuits once we master the classic crane model, but the mathematics behind origami can lead some practitioners past the pure art to more practical structures, like this folding ballistic barrier for law enforcement use.
The fifty-pound Kevlar and aluminum structure comes from Brigham Young University’s College of Mechanical Engineering, specifically from the Compliant Mechanisms Research program. Compliant mechanisms move by bending or deflecting rather than joints between discrete parts, and this ballistic shield is a great example. The mechanism is based on the Yoshimura crease pattern, which can be quickly modeled with a piece of paper. Scaling that up to a full-sized structure, light enough to be fielded but strong enough to stop a .44 Magnum round, was no mean feat. But as the video below shows, the prototype has a lot of potential.
Wars generally increase innovation as the opposing sides try to kill each other in ever more efficient ways. Even the soft war waged daily between felines and their human servants results in innovation, to wit we offer this armor-plated automated cat feeder.
The conflict between [Sprocket H.G. Shopcat] and her human [Quinn Dunki] began with a thoughtfully provided automatic food dispenser. Like human vending machine customers who witness a just-purchased bag of Cheesy Poofs dangling on the end of the dispense auger, [Sprocket] learned that the feeder would dispense a few fishy nuggets when nudged. [Quinn] embarked on an iterative design process to control [Sprocket]’s off-schedule snacking. Fastening the feeder firmly to the floor, and adding obstructions to prevent her from pawing up the dispense chute — nothing seemed to stop the clever feline’s raids. [Quinn] then pulled out all the stops and whipped up a [Sprocket]-safe enclosure for the feeder from 1/8″ plate steel and copper. This seems to have put the cat back on the straight and narrow, and it doesn’t look half bad either.
All kidding aside, [Quinn]’s approach to this problem is pretty instructive. Careful observations informed several cycles of reasonable modifications until it became clear that only the most extreme solution would work. There’ve been tons of cat feeders here before, from the simple to the complex, but we think all would fall prey to the clever [Sprocket] without a little up-armoring.
For most of us, hacking is a hobby, a pleasant diversion from reality. Yes, a lot of us work on projects which have the potential to change the world – witness the 2015 Hackaday Prize semifinalist list. But in general, almost any of us could walk away from the shop at any time without dire consequences. Indeed, that’s the reason a lot of our work benches are littered with projects started with the best of intentions but left unfinished for lack of funds, lack of interest, or lack of time. We’re free to more or less willingly shelve a project and come back to it whenever we please, or not at all.
But not everyone has that luxury. For some people, hacking is much more than a hobby – it’s a means of survival. Sometimes people are thrown into situations where they have to cobble together a solution to an immediate problem with whatever is at hand, when the penalty for failure is much higher than a cluttered bench and a bruised ego. I’ve already covered one such case, where biohacked insulin saved hundreds of lives in occupied Shanghai in WWII.
In this occasional series I’ll explore historical cases where hacking really counted; cases where lives were saved or improved by a hack performed under desperate conditions.
A Bustle in the Hedgerow
Unsurprisingly, war offers a lot of opportunities for field expedient solutions under dire circumstances, and battlefield conditions might be the most extreme example of hacking when it counts.
In the early days of the Invasion of Normandy during WWII, Allied forces were having a difficult time dealing with the bocage terrain of northern France. A mixture of pasture and woodland, the Normandy bocage was a natural killing field for Allied tanks because the woodlands took the form of hedgerows – earthen dikes topped with thick tangles of brush. Hedgerows separated pastures and kept livestock controlled, but also made things tough on infantry and mechanized cavalry alike. Climbing the steep hedgerows exposed the vulnerable bottom hull of the tanks to enemy fire, and waiting for engineers to demolish the hedgerows with explosive made them sitting ducks for German artillery. The Allied advance was seriously hampered by the hedgerows, and both men and materiel were being winnowed down from fixed German positions chosen specifically to take advantage of the bocage terrain.
Enter Sgt. Curtis Grubb Culin III. Sgt. Culin, a tanker himself, was acutely aware of how vulnerable he was in his Sherman M4. The hedgerows were the problem, one apparently known to Allied command prior to the invasion for which no provision had been made. In the tradition of soldiers at the front of every battle throughout history, Sgt. Culin and his fellow tankers had to improvise a solution.
While kicking around ideas, one of the men suggested setting saw teeth on the front of a tank to cut through the hedgerows. He later attributed the comment to “A Tennessee hillbilly named Roberts”, and it was met with general laughter from the group as a crackpot scheme. But Sgt. Culin saw the potential in the idea, and began to develop it into a prototype.
Raw materials for his prototype were not hard to come by. Czech hedgehogs, giant anti-tank barriers made of crossed steel beams, still littered the Normandy beaches. The failed German defenses were harvested with a cutting torch and welded to the underside of a tank to form a series of “tusks” across the hull between the tracks. Equipped with these tusks, the tank could now blast through the tangled roots of the brush-covered earth of the hedgerow dykes.
When demonstrated for General Omar Bradley, he was impressed enough to order them built in quantity for the tanks. Eventually the prototype became an engineered product (dubbed the “Culin Rhino Device”) that was fitted to many tanks before being shipped over from England. Rhino-equipped tanks ripped across Normandy and shredded the German battle plan, which assumed the hedgerows would funnel Allied forces through heavily defended chokepoints.
Without Sgt. Culin’s battlefield hack, and his inspiration by a hillbilly named Roberts whom history otherwise forgets, the invasion of Europe might have taken a very different course. The fact that he did the hack while under fire makes it all the more impressive, and is a perfect example of hacking when it counts.
Know of any more examples of hacking when it counts? Send us a tip for use in a future Hacking When it Counts article.
We know that armor making is an art form. We know it. Still… it’s really easy to let yourself think that making a chain mail shirt is easy after seeing the skills [KdogCrusader] throws down in this build. His hauberk isn’t quite finished yet, though we don’t blame him from wanting to show off the work having put so much into it.
The process starts with fifty pounds of stainless steel wire. That’s the coil suspended on a rod in the upper left. It’s fed into his hacked together coiling jig where it is wound into coils that set the diameter of the rings (think long springs that aren’t springy). Coils are cut along one side resulting in that mountain of individual rings. From there it’s a matter of interlinking all of the rings. He cut apart an old T-shirt to use as a pattern during the assembly. So far the front and the back are only connected at the shoulders as he has yet to add sleeves and finish the sides.
What does a hacker do when going into battle for the freedom of their country? He builds a tank from scratch, of course. It’s a little bit of a stretch calling it a tank as it lacks treads. But it’s got a high-caliber gun mounted on top and has been heavily armored.
There is room enough inside for two people. What may look low tech in this picture is a different story from the cockpit. A pair of LCD monitors display images from five different cameras. You can see the shrouds that protect three of them on the front of the vehicle with a fourth acting as the rear view. A fifth camera mounted on the gun gives the passenger a look at where he’s aiming. A PS1 controller can rotate it and we assume has a fire feature as well. Check out the demonstration video embedded after the break.
This is not photoshopped, it’s a real gauntlet made of brass. [David Guyton] crafted it for some promotional photos for his book. But he also took the time to put together a step-by-step build tutorial.
The process starts with paper templates. These are much easier to work with than metal stock so [David] spends quite a bit of time trimming each piece to fit correctly. They are hinged together using thumb tacks which he crimps with a pair of pliers. With all the templates tuned to perfection he uses an awl to scratch the outline in his brass stock (you can use the metal of your choice). All of the holes are drilled and a bit of hammering flattens the parts before he heads to the grinder to smooth the cut edges.
To make the curves [David] fabricated his own jigs from pieces of pipe and carved wood squeezed together with a bench vice. It’s time-consuming, but the skills needed should be rather easy to develop with a little practice. You can catch his entire build in the video after the break.