Mirage 2.0 Lights up the desert with 4,024 LEDs

Registering a mutant vehicle at the Burning Man Department of Mutant Vehicles (DMV) is rough. To be allowed to operate at night, wacky rolling creations have to have a certain degree of lighting presence. This keeps vehicles  from blending into the scenery. Unfortunately Mirage 1.0 was built specifically with this in mind,  using reflective surfaces to turn a van into a semi-invisible shiny slab. Not even EL wire, an illuminated dance floor, and spot lights could placate the DMV. The solution? Wrap the entire friggen vehicle in a netting of 4,000 LEDs! Take that officials!

Most of the hardware is Phillips display stuff, digital LED fixture controllers are used to interpret HDMI data and then pipe out color data to addressed chains. All this mapping and addressing means that the entire setup functions like a 168×24 pixel monitor.  Split chains of LEDs also happen to allow the crew to operate the doors and get in and out of the vehicle.

The underlying car was built on the same sort of principal that hid the wheels of  Skywalker’s landspeeder, only in this case the idea was to cover an entire car with mylar and mirror. An interesting side effect of this mirror wrapping is that a sheen of desert dust helps reflect the ambient LED light quite well, blurring pixel colors together. It sort of makes us wonder about picking up a bucket of Mylar for some of our spaced out displays.

The Mirage crew has plans for next year, and have videos of several ideas on the site (portions of the test videos are NSFW).  Check out the video of Mirage 2.0 in action after the jump! Thanks [erland]!

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Cheap spark detector for alpha particles

[JAC_101] wrote in to let us know that the Truely Mad Scientist’s LVL1 Splinter Group just built a simple Alpha Particle detector.  The detector is a high voltage DC spark gap that is triggered by ionizing radiation. Making one of these detectors involves gutting a cold cathode power supply for some high voltage AC, then bumping that source up to crazy high voltage DC with a Cockcroft-Walton generator.  Once the spark gap distance is carefully adjusted it will light up brilliantly with the introduction of a radioactive source, we are told. There are no videos, or even pictures of the thing running, but we found this one that is pretty darn cool. Maybe all that spark-gap related RF killed their camera or something, their page at least promises videos soon.

In the mean time check out Truely Mad Scientist’s LVL1 Splinter Group’s ionizing cloud chamber for more radioactive fun.

How TO dim EL wire: Current limiting the oscillator!

[Ch00f] finally made a breakthrough with his efforts dimming EL wire.  He’s been at it for months and the last we heard his TRIAC idea had sputtered out. Not to be discouraged and with an determination we have to admire he has been hard at work reverse engineering others’ and developing his own methods. He put all of this knowledge to task helping a friend of his with a sleeping disorder, and made a dream-catcher that pulses at the approximate rate of an average person’s breathing (as determined by Apple for their pulsing power button lights).

Essentially the whole thing boils down to simply using a transistor to limit the current to the oscillator. A 555 timer is used to pass a triangle wave to the current limiting transistor at approximately the same rate as the Apple button (1/5 Hz). [Ch00f] notes that this isn’t the sinusoidal wave that apple uses, but it’s good enough. Finally a timeout power off is built in to the night light using a decade counter to monitor the number of triangles from the 555. This should keep the EL wire from wearing down faster, though we are hard pressed to  think of a project we used EL on that has lasted anywhere near the 7 year service life of the wire.

Check out [Ch00f]‘s page as he walks us through the process, or just watch his circuit in action after the jump!

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L.I.O.S.: The ten-ish dollar robot.

We love cheap stuff here. Who doesn’t? [Oscar Rodriguez Parra] does too, and wrote in to show us his super cheapey robot L.I.O.S. The build was for the AFRON design challenge, which involves building a 10 dollar robot to teach students robotics. The winners of the challenge were neat and all, but they all look too fancy flaunting their molded plastics and electronics breadboards.

[Oscar's] design is super simple, LDRs as eyes, a PIC12F683 to do the brainin, LEDs for indicators and a couple modded servos to drive the wheels. An extraordinarily complex cardboard flap roller helps the cart turn, but probably isn’t going to see much aside from smooth flooring. The electronics are mounted using one of our favorite techniques, the paper perf board (very similar to the substrate free technique).

Check out the video after the jump to see LIOS in action. This is an excellent introduction to robotics for any classroom. Thanks [Oscar]!

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Honey bee temperature logger tracks internal hive movement

Apparently bees tend to use different areas of the hive throughout the year. All we know is not to mess with them. [Max Justicz], on the other hand, does exactly that at his high school. He built a whether resistant solar powered multi-point temperature logger to do such things. The logger is designed to track heat movement within the hive throughout the year. Bees can be tracked like this because they generate a good amount of heat, some even use it to kill off predators.

Building weather resistant electronics is no picnic. You have to deal with rubber O rings, cable glands and clunky waterproof connectors. [Max] shows the whole process of mounting the various components into the enclosure. A solar panel feeds an Ardunio Mega, charging electronics, and SD card shield. With a 1GB SD card this bugger is in for a long haul. The 6600mAh battery should keep it running excessively long though. We’d cut the fat a bit though and swap out that Mega for something less power hungry, but going super low power can get a bit fancy. That mega is powerful enough to incorporate every other bee project we have here.

[Max] has yet to install the logger in his high school’s apiary but will update with logs once he can furnish them. We can’t wait to see the patina it develops over the seasons.

Test your project’s mettle with a protected dummy load

For a power hungry project the supply is sometimes a pretty big unknown. Whether stapling together a few different power supplies to meet a current requirement, or designing a system from the ground up: a big power supply can be quite a dangerous thing. It helps to have some kind of a dummy load to really shake down the electronics and get an idea of how hot things get or test stability before trusting the supply to run your stuff. [Paulo Oliveira] has constructed just such a thing, a slick looking adjustable constant current load.

Following the popular LM324 circuit from [David Jones] at EEVblog [Paulo] decided to make use of the two spare op-amps to provide both a thermal overload and a cooling fan circuit. We have seen other tweaks to [David]‘s circuit in the past but through some resistors and MOSFETs [Paulo] can now load up to 7A (limited by resistor wattage). We would have used a really crazy server vacuum fan to make it genuinely frightening to push heavier loads. Thanks [Paulo]!

mbed and a few resistors runs console, VGA, and PS/2

[Jordan] writes in to show us a project he has been working on called MbedConsole. Living up its name [Jordan] has managed to run a 640×480 VGA output, PS/2 port and console all from the mbed itself. We really mean from an mbed only; no extra hardware is required aside from a few resistors and connectors, a VGA monitor and PS/2 keyboard. The code is open source and links are included in the blog. There are even instructions for including your own graphics.

There are a few things to tackle still, like SD card support. Currently the PS/2 keyboard lights for caps-lock are not functional. [Jordan] would love to know what else we’d see going on something like this, with 400k of flash and 20k RAM left there certainly is a bit of room for some interesting stuff. One of his main goals is to get rid of the C interface and port an interactive shell over that could do something like BASIC or Forth (to give it that retro environment feel). We have seen the mbed in a handful of projects, what do you think?