NYC CCTV Scouting

nypd

On a recent trip to New York City, [sherri] noticed the abundant “NYPD Security Camera” signage. She Ò on her little sousveillance tour and did some digging to learn more about the system. According to a recent NY Post article, the city intends to have 2,000 cameras installed by 2009. Each unit has at least two cameras, an onboard DVR, battery backup, a webserver, and wireless connection. The CrimeEye product line is manufactured by Total Recall—the people who brought you BABYWATCH. While the company site doesn’t list any specs, we found a price list that was provided to New York State. Each unit lists for $28-39K. They can have image sensors up to 2 megapixels, hold 30fps video for 5-15days, and transmit wirelessly on the 4.9GHz public safety band.

[sherri] wonders what systems are in place to guarantee the security of the camera network and to make sure the data is handled properly. We’ve seen bad implementations of cameras with webservers
in the past. She suggests a third-party system to verify security, operation, and storage. Right now there’s no reason the government won’t use footage for invasive data mining. As a publicly funded system monitoring public areas, we see no reason why the video streams from these devices shouldn’t be widely available.

[Thanks Tendency]

Working With VFDs

vfd

We love old display technology, like Nixie tubes, but they’re often difficult to work with because they require higher voltages than digital logic. Vacuum florescent displays (VFD) fall into this category. While not necessarily “old”, they are becoming far less common than LCDs. The main benefit of a VFD is that it actually produces light directly; it doesn’t require a backlight. You’ll find these displays on various players and appliances: CD, DVD, VCR, microwaves, stoves, car headunits, and others.

[Sprite_tm] had written off some VFDs, but recently revisited them with renewed interest. He started by testing what sort of voltage would be required to drive the display. It took 3V for the filament plus 15V to drive the grids. There are VFD controller chips available, but he wanted to get this working with what he had on hand. He had experience with older 40xx series logic, which can be powered by much higher voltages than 5V 74xx. His final schematic has three 4094 serial to parallel chips with an ATtiny2313 controller. A 5V power supply is dropped to 3V with diodes to drive the filament while a boost converter brings it up to 15V for the 4094s that switch the segments. While the code is specific to this display, it would be a great place to start your own project.

RepRap Motherboard

reprapmb-1

When the RepRap team found themselves pushing the limits of the Arduino, they started looking for alternatives. They found it in the ATMega644P. It has four times the memory and four times the RAM compared to the ATMega168 used in the standard Arduino. It also has 32 I/O pins. They ported the Arduino software to the microcontroller and started producing Sanguino boards. Now that the base design is nailed down, they’ve begun expanding it to their specific purpose. Pictured above is a prototype RepRap motherboard. While the Sanguino is barebones, this board has onboard connectors for all of the RepRap’s motors, so you can just plug it in. It is also designed to support the future Generation 3 electronics. Probably the most interesting feature is the SD card slot. The goal is to eventually have a board that can run the RepRap without a host computer if necessary; it will manufacture designs directly from the flash card.

Pelican Case Xbox 360

pelicanxbox

[Ben Heck] has put the final touches on his Pelican case Xbox 360. This prototype was constructed for use by troops stationed overseas. When he announced the project in October, he already knew some of the hurdles he would face. An industrial Velcro style product is used for all component mounting so the air/water-tight seal of the case remains intact. He sanded the surface so that it would stick better. [Ben] mentions that he ended up using less Velcro than he planned on because it held so well. Not being able to cut the case meant the DVD drive had to be converted to top-loading. The tray movement limit switches have been relocated so they now respond to lid position. He regrets not being able to motorize the lid, but let it go since this is still just the first attempt. Extra copper was added to all of the heat sinks to improve cooling. This Xbox is for sale and he’d love to hear from anyone that wants to put it into production. The write-up has a ton of pictures and you can see a video of it below.

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Giant LED Lamp

led

[guyfrom7up] must really really love LEDs. When he needed some lighting, which would obviously be LED powered, he chose to actually build a giant LED. Well, he didn’t actually build a giant functional LED, but rather an LED shaped diffuser for some high powered LEDs. He takes us through the process of first creating a wooden model, using that to create a mold, then forming the final diffuser.  The final product is very well done, and instantly identifiable by any geek.

[thanks Brian]

Multitouch MAME Cabinet

mame

[rdagger] sent us this really well done multitouch MAME cabinet build. He ha penned to find a used, and fairly worn cocktail cabinet. The monitor was damaged, keys lost, and internals had been home to mice for some time. He promptly tore out the old guts, replaced the smelly mouse damaged base and began building the projection system. For touch sensing, he’s using a web cam with the IR filter removed to detect disturbances in some IR laser beams. We’re not completely clear on how he mounted the lasers, he skips over that part.  There’s nothing groundbreaking in the technology here, we’ve done multitouch many times before. This project stands out in its execution. [rdagger] has done a fantastic job, the construction looks fantastic.  Check out a video of it working after the break.

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Parts: 1K 1-Wire EEPROM (DS2431)

1keeprom-450

The Maxim DS2431 1K EEPROM is 1-Wire device that adds storage to a project using a single microcontroller pin. We previously interfaced a 1-wire thermometer, but this EEPROM is slightly different because it draws power directly from the 1-Wire bus. Grab the datasheet (PDF) and follow along while we read and write this simple 1-Wire memory.

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