Underwater ROV

[SpaceShipOne] has built this very nice looking under water ROV.  It is still a work in progress, but nearly complete.  This ROV is a fairly simple construction. most of the body parts are held together using zip ties.  There’s no microcontroller and no custom boards.  He’s using a radio control transceiver that was intended for airplanes to control some standard speed controllers and servos.  For thrust, he pulled the motors out of some bilge pumps and fitted them with propellers.  He’s only tested it once, but promises videos from the lake soon.  He mentions [Jason Rollette] several times since [Jason] has done both simple and complex designs in the past.

Laser POV Projector

[shakirfm] sent us this LED persistence of vision (POV) laser projector that can display dot matrix style text. The laser projector contains a rotating mirror assembly and 5 lasers. We’ve covered other POV projectors,but this one is a bit different. The mirror assembly rotates using two cooling fans. Controlling on/off times of the lasers along with the mirror speed, it is able to project 8×5 dot matrix ASCII text onto a surface.
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Parts: LM317 Adjustable Voltage Regulator

Every project needs a power supply. As 3.3volt logic replaces 5volt systems, we’re reaching for the LM317 adjustable voltage regulator, rather than the classic 7805. We’ve found four different hobbyist-friendly packages for different situations.

A simple voltage divider (R1,R2) sets the LM317 output between 1.25volts and 37volts; use this handy LM317 calculator to find resistor values. The regulator does its best to maintain 1.25volts on the adjust pin (ADJ), and converts any excess voltage to heat. Not all packages are the same. Choose a part that can supply enough current for your project, but make sure the package has sufficient heat dissipation properties to burn off the difference between the input and output voltages.

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Broken LCD TV Turned Into A Light Table


[Steve DiRaddo] sent us this sweet little mod. After obtaining a free LCD TV that had a cracked screen, [steve] immediately tore it open to re purpose it. The end result was a computer controlled light table with audio. From what he says, it is very very bright due to the fact that it has 16 CFL tubes behind it as opposed to the usual 2 inside a PC monitor. The TV had a bult in RS232 command port. Whith some quick hacking, he was able to control power, channel, input, and volume via his laptop.

Real Time Gas Monitoring

With the weather getting colder, [Daniel] decided it would be a good idea to monitor how much energy his gas heating was using in real time. He used a Nokia 6680 cameraphone to monitor the heater’s flame through the sight glass. PyS60, a Symbian implementation of Python, checks the image sent by the camera and measures how much blue flame is visible. These values are stored in a SQL DB on the phone that can be polled over Bluetooth. At the end of the billing cycle,  he’ll be able to correlate the amount of gas used with what the phone reported.

[Thanks, florent bayle]

Direct To Garment Printing

[youtube=http://www.youtube.com/watch?v=f3iOuKzhUlQ]

Reader [deren lik] pointed out the world of direct to garment printing to us. You can purchase commercial machines that will print directly onto a t-shirt using inkjet technology. Unfortunately, these machines cost ~$10K, so hackers have decided to fill in the gaps. DIYDTG hosts plans for how to build your own DTG printer. Their standard instructions are based around the Epson C88 printer. A custom carrier is constructed and then the printer components are bolted on top. Commercial DTG printers are also based on Epson parts and you can easily purchase the garment inks even if you didn’t pay a premium for your printer.

Daily Photo Aging Project On Steroids

We’ve seen those videos where people take a picture of themselves every day. [Dan Hanna] took it to a much further level.  He built a camera rig and took pictures of himself for 17 years.  That is not a typo, 17 years. The rig consists of a ring that holds two cameras opposing each other.  He centers his head facing a target that he increments around the ring every day before taking a picture.  The ring can be split into 4 sections for portability.  Check out the low resolution video after the break.

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