Author Archives: Steven Dufresne

Soft Hydraulic Muscles Lift Weights As A Team

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Working with hydraulics usually means having a fluid tank and valves. [consciousflesh] does away with both those for his DIY hydraulic artificial muscles. Instead, he uses a pair of muscles, both preloaded with fluid. To contract one, he pumps the fluid into the other, expanding that one, and vice versa. A bidirectional gear pump moves the fluid while also acting as a valve. And flexible materials replace heavy metal cylinders.

As we said, this is a DIY project. He made the muscles by surrounding silicone tubes with aramid fiber sleeves, giving added strength. The blocks at either end are also …read more

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Tracking The Office Coffee Machines Using Current Draw

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Coffee is the lifeblood of hackers, IT workers, and apparently, IT workers who are also hackers. [Omerfarukz] is clearly the latter. He works as part of a large team spread over multiple floors, all with coffee machines, any one of which is fair game. The problem is knowing which one has coffee that is ready to pour. He needed a non-invasive way to monitor the coffee machines.

After contemplating a few solutions, he opted for one which wouldn’t offend the coffee gods. The machines use a high current to produce their heat, so he adapted some old remote control power …read more

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Kathleen Booth: Assembling Early Computers While Inventing Assembly

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Imagine having to program your computer by rewiring it. For a brief period of time around the mid-1940s, the first general-purpose electronic computers worked that way. Computers like ENIAC initially had no internal storage for code. Programming it involved manipulating thousands of switches and cables. The positions of those switches and cables were the program.

Kathleen Booth began working on computers just as the idea of storing the program internally was starting to permeate through the small set of people building computers. As a result, she was one of the first programmers to work on software and is credited with …read more

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OMEN Alpha: A DIY 8085-Based Computer

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[Martin Malý] has put together a sweet little 8085-based single board computer called OMEN. He needed a simple one for educational purposes, and judging by the schematic we think he’s succeeded.

Now in its fourth iteration, it has a 32K EEPROM, 32K of memory, one serial and three parallel ports. In the ROM he’s put Tiny BASIC and Dave Dunfield’s MON85 Serial Monitor with Roman Borik’s improvements. His early demos include the obligatory blinking LED, playing 8-bit music to a speaker, and also a 7-segment LED display with a hexadecimal keyboard. There is also a system connector which allows you …read more

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Restoring A 100 Year Old Vice To Pristine Condtion

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We love our vices. They hold pipes for us to saw away at, wood while we carve, and circuit boards so that we can solder on components. So we keep them in shape by cleaning and greasing them every now and then, [MakeEverything] went even further. He found a 100-year-old vice that was in very rough shape and which was going to be thrown out and did a beautiful restoration job on it.

It was actually worse than in rough shape. At some point, one of the jaws had been replaced by welding on a piece of rebar where the …read more

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How The 8087 Coprocessor Got Its Bias

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Most of us have been there. You build a device but realize you need two or more voltages. You could hook up multiple power supplies but that can be inconvenient and just not elegant. Alternatively, you can do something in the device itself to create the extra voltages starting with just one. When [Ken Shirriff] decapped an 8087 coprocessor to begin exploring it, he found it had that very problem. It needed: +5 V, a ground, and an additional -5 V.

His exploration starts with a smoking gun. After decapping the chip and counting out all the bond wires going …read more

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Theo Jansen Invents A Faster, Simpler, Wind-Powered Strandbeest

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[Theo Jansen] has come up with an intriguing wind-powered strandbeest which races along the beach with surprising speed and grace. According to [Jansen], it “doesn’t have hinging joints like the classical strandbeests, so they don’t get sand in their joints and you don’t have to lubricate them.” It’s called UMINAMI, which appropriately means “ocean wave” in Japanese.

There are only videos of it in action to go on so far, but a lot can be gleaned from them. To make it easier to keep track of just a single leg, we’ve slowed things down and reddened one of them in …read more

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Converting A 3-in-1 Printer Into A WiFi Scanner, Just Because

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[Zaprodk] had trash-picked a defunct HP Envy 450 AIO, a 3-in-1 printer, scanner, and copier. Normally there usually isn’t much use for these unless you’re willing to hunt down the cartridges which it used, so your next step is to dismantle it for parts. That’s what he was going to do but then decided to see if he could remove as much as possible while leaving just the scanner.

He ran into trouble after he’d “fixed” the lid-open sensor and unplugged pretty much everything. He was getting too many error messages on the LCD panel to reconfigure the WiFi. Luckily …read more

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Project Orion: Detonating Nuclear Bombs For Thrust

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Rockets with nuclear bombs for propulsion sounds like a Wile E. Coyote cartoon, but it has been seriously considered as an option for the space program. Chemical rockets combust a fuel with an oxidizer within themselves and exhaust the result out the back, causing the rocket to move in the opposite direction. What if instead, you used the higher energy density of nuclear fission by detonating nuclear bombs?

Detonating the bombs within a combustion chamber would destroy the vehicle so instead you’d do so from outside and behind. Each bomb would include a little propellant which would be thrown as …read more

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Hacking A Solar Bubble Blaster With Grandkids

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[Fmilburn] was having fun with his grandkids, playing around with a small Radio Shack solar panel, some supercapacitors and a Zener diode when the kids eventually moved on to blowing bubbles with their grandmother. To regain their interest he got an inexpensive battery powered, soap Bubble Blaster and converted it to run on the solar panel and supercapacitors instead.

His write-up is a pretty fun read, walking through his process, including an oscilloscope measurement showing how the capacitors’ voltage drops from 5.26 V to 3.5 V when the trigger is pressed, and interestingly, slowly recovers until it’s released a second …read more

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