Improved Arm Mounted Flame Thrower

prometheus-flame-thrower[Everett] is at it again with Prometheus, an arm mounted flame thrower.This is the third generation of the project and makes some huge advances over the second generation we saw last year. We’d say he’s reached cinema/stage-performance quality with his design.

The self-contained system is completely arm mounted with a fuel reservoir mounting behind the elbow. The new version adds an adjustable flow valve actuated by a servo motor to regulate the flame size. An arc generator has been incorporated to replace the lighter from the last version. A microcontroller measures wrist angle and takes care of creating the arc and regulating the fuel supply.

Prometheus is small, controllable, and frightening. See a full demonstration as well as some video of the prototyping process after the break. Does this make you wonder how much burn cream [Evertt’s] needed over the years?

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Processor Built With Transistor-Transistor Logic

cpu-built-from-ttl

[Donn] wanted know exactly what is going on inside of a processor so naturally he built a CPU out of TTL components. He had previously built a couple of versions of a computer based on the Z80 processor. Using the troubleshooting skills he learned and a second-hand textbook, he set to work using 74LS series chips connected using the wire-wrap method we’re familiar with from other cpu projects.

The finished product runs well at 1.8 megahertz, but he also included a 2 hertz clock and a step clock for debugging. At the slower speeds, the register board (seen at the left in the picture above) lights LEDs and can be used to tell what the CPU is currently working on. Programming is accomplished through either  a dumb terminal or a PC running a terminal emulator.

His writeup is from about five years ago but that didn’t prevent us from getting that fuzzy feeling in the geek-center of our brain when we read about it. It is well written and thorough so if you’re into this kind of thing there’s plenty to enjoy.

[Thanks Raleigh]

Arduino “python” Integration

vivarium

[Cyberspice] informs us she likes snakes. Hey, who doesn’t? She’ll soon be adopting a lovely ball python and wanted to keep close tabs on the sensitive creature’s environment. To that end she assembled a network-enabled vivarium monitoring system based on Adafruit’s Boarduino (a minimalist Arduino clone), a TMP36 analog temperature sensor, Saelig’s WIZ810MJ Ethernet interface, and a common LCD screen. The Arduino rig periodically issues updates to a web server, which can then generate informative graphs using a set of PHP scripts (what, no Python?).

Okay, so we could probably count on one hand the number of readers in need of fancy reptile monitoring and still have fingers left over. There are countless other applications where networked sensor monitoring of this sort is a frequent necessity, so the article could be a good starting point for your own projects. There’s lots of source code to work with, on both the Arduino and web server sides. And the parts list demonstrates serious frugality: the Boarduino, the generic LCD, and especially the Ethernet interface; even with the breadboard adapter, this unit is about half the cost of the usual Arduino Ethernet shield, leaving more funds available for the snake food budget!

Digital Tuner Reverse Engineering

hvr-1600-i2c-sniffing

Hackaday alum [Ian Lesnet] tipped us off about some reverse engineering of the HVR-1600, an analog and digital television encoder/tuner. The project was spawned when [Devin] noticed his Hauppauge HVR-1600 didn’t tune channels in Linux quite as well as it did in Windows. He had a hunch this was due to improper initialization settings for either the tuner chip or the demodulator.

To fix this he used two test points on the board to tap into the I2C bus. Using a logic analyzer he captured the command traffic from the bus while running Linux, then while running Windows. By filtering the results with a bit of Perl, and comparing them by using diff, he tracks down and finds the variation in the commands being sent by the two drivers. After a bit of poking around in the Linux source and making the necessary changes, he improved the tuning ability of the Linux package.

[Devin’s] work looks simple enough, and it is. The difficult part of this process is being smart enough to know what you’re looking for, and what you’ve got once you’ve found it.

Head-mounted Computer With Spit, Bailing Wire

[youtube=http://www.youtube.com/watch?v=QyrjBMAa6xE]

Oh, for crying out loud! While we were all giddy reporting on yesterday’s wonderfully done head-mounted computer, [Andrew Lim] of recombu.com comes along and essentially does the same thing with an HTC Magic handset and three dollars worth of Harbor Freight crap. Linux kernel, WiFi, accelerometer, the whole nine yards. Consider our collective ass handed to us.

Funny thing is, either of these could be considered The Consummate Hack. One flaunting the creator’s know-how with its custom-designed parts and delicate engineering, the other exhibiting a more punk flair with random scraps and off-the-shelf technology achieving much the same effect — a solution so obvious we were blind to it. Whatever your outlook, this is a great day to be a hacker!

[via slashdot]

Head-mounted Computer With Linux, WiFi

hmdlinux

Most wearable computers we’ve seen feature a head-mounted display tethered to a small PC system in a backpack or worn on a belt. Here’s a slick little system that does away with the cord, fitting the entire system in the glasses.

[Pascal Brisset’s] WXHMD is based on the tiny Gumstix Overo Fire computer-on-module which features a beefy, 3D-capable OMAP processor that runs Linux. The Gumstix is interfaced with a Vuzix VR920 head-mounted display that includes a three-axis accelerometer and compass. Tying these together is a custom video digital-to-analog converter board of [Pascal’s] own design, created using direct-to-PCB inkjet printing techniques. For less than $1,000 total in parts, the result is a spatially aware six ounce computer, with display and battery and all, that fits neatly over the bridge of one’s nose.

It’s a fantastic hack and a nicely documented project, though even the device’s creator himself questions whether having a pair of microwave transceivers and a LiPo battery strapped directly over one’s eyes and brain is such a good idea.

[thanks w3pt]

DIY Plotter With Laser

plotter-with-300w-laser

[Viacheslav] built a plotter that is fast and accurate. He wanted to take it one step further and added a laser in place of the pen. The 300 mW unit does a nice job of wood-burning any pattern sent to it, but isn’t strong enough to serve as a laser cutter for anything other than thin-film. We wonder if it can be used to cut solder paste stencils for surface mount PCB production.

In the video after the break you can see some plotting that uses a pen. In addition to writing on paper, [Viacheslav] has tested this as a method of applying etch resist to a copper clad board for PCB production. He’s able to achieve 0.8 mm pitch but the production process is limited by the resist pen’s tendency to wear out quickly and to only prevent etching for a short period of time (compared to toner transfer resist).

Just like with his touch sensitive keypad project, he’s taken the time to thoroughly document his work. Build notes, pictures, CAD files, and source code are all available for your perusal and hackage.

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