Retrotechtacular: Turn On the Magic of Colored Light

title cardChances are, you take color for granted. Whether or not you give it much thought, color is key to distinguishing your surroundings. It helps you identify fire, brown recluse spiders, and the right resistor for the job.

In the spotlight this week is a 1950s educational film called “This is Color“. It also happens to be a delightful time capsule of consumer packaging from the atomic age. This film was made by the Interchemical Corporation, an industrial research lab and manufacturer of printing inks. As the narrator explains, consistent replication of pigments is an essential part of mass production. In order to conjure a particular pigment in the first place, one must first understand the nature of color and the physical properties of visible light.

electromagnetic spectrumEach color that makes up the spectrum of visible rays has a particular wavelength. The five principal colors—red, yellow, green, blue, and violet—make possible thousands of shades and hues, but are only a small slice of the electromagnetic spectrum.

When light encounters a transparent material more dense than air, such as water or glass, it has to change direction and is bent by the surface. This is known as refraction. A straw placed in a glass of water will appear bent below the surface because the air and the water have different refractive indices. That is, the air and water will bend or refract different percentages of the light that permeates them. Continue reading “Retrotechtacular: Turn On the Magic of Colored Light”

Building a Network Controllable RGB LED Lamp from an Old Scanner

EthernetLamp

Being able to use one of your old projects to make a new one better can be quite satisfying. [Steve] from Hackshed did just this: he integrated an Arduino based webserver into a new network controllable RGB lamp.

What makes this lamp unique is that the RGB LED bar comes from an old Epson scanner. Recycling leftover parts from old projects or derelict electronics is truly the hacker way. After determining the pinout and correct voltage to run the LEDs at, the fun began. With the LED bar working correctly, the next step was to integrate an Arduino based webserver. Using an SD card to host the website and an Ethernet Arduino shield, the LEDs become network controllable. Without missing a beat, [Steve] integrated a Javascript based color picker that supports multiple web browsers. This allows the interface to look quite professional. Be sure to watch the lamp in action after the break!

The overall result is an amazing color changing lamp that works perfectly. All that is left to do is create a case for it, or integrate it into an existing lamp. This is a great way to use an LED strip that would have otherwise gone to waste. If you can’t find a scanner with a color wand like this one, you can always start with an RGB strip.

Continue reading “Building a Network Controllable RGB LED Lamp from an Old Scanner”

Building Mosaic LEGO Lamps

LEGO_MOSAIC

Looking for a throw back to your childhood, or maybe you just appreciate things that light up and look amazing? Well, [Baron] has a really impressive project for you. Not only does it look stunning and incorporate all of the things we love, it’s actually a pretty novel design. These lamps are built completely out of LEGO Technic pieces, the brand of LEGO that have holes drilled through them so you can build more advanced creations.

[Baron] used these parts with the drilled holes to create a dot matrix in which he placed colored transparent LEGO dots in the holes. The method of creating patterns is very similar to the way it’s done on the “Lite-Brite”. We especially love the theme of these lamps and they would match well with your LEGO mystery box. What’s really great about this tutorial is that it lays down the foundation for LEGO-built lamps that could be more interactive, involve more control (like RGB LEDs), or even introduce some LEGO mechanics!

Cast acrylic and wood LED light

LED-ring-light

The design for this LED ring lamp started off as a cross-section sketch. [Alex Jalland] envisioned a core that holds the parts and hides the circuitry, with two halves of a clear doughnut diffusing the light and covering everything up.

For the core itself he headed over to the lathe and turned a piece out of ash. He tooled the profile into one side, flipped it around to form the other, and finally cut the center out to form a ring. This may sound like a lot of work, but it pales in comparison to what went into the diffusers.

He cast the parts out of polyurethane resin. This required a mold which he made from scratch. The process used many materials, including a vacuum forming machine, a latex slug, and plaster to keep the thin mold from deforming when filled with resin.

The lamp provides a lot of light. But with this much work put into the enclosure we’d suggest going the extra mile to make it an Equinox Clock clone.

SenseLamp automates rooms by replacing light fixtures

senselamp

Would you believe that this beautiful light fixture is actually a hacked together home automation project? Okay, so this wire mess is the second of three versions that [Christian] built. It replaces a light fixture in the room, but if you look closely you’ll see that there is a compact fluorescent bulb included in the build. The laser-cut frame acts as a bit of a lamp shade, while providing a place to mount the rest of the hardware.

The final version cleans things up a bit, and adds a footprint for the PIR motion sensor that he forgot to design into this version. The idea is that each lamp monitors motion in the room, switching the light on and off again as necessary. A light-dependent resistor ensures that the bulb is only powered up if the room is dark so as not to waste electricity during the day.

The build includes a sensor package that reports back temperature and humidity data. Communications are provided by a WR703N router rolled into each of the four units installed in his house. With this kind of hardware at his disposal it should be a snap to control every IR remote control device in his house via the network by adding an IR LED and some code to the lamps.

Brilliant auto-off feature for a bike light

auto-off-bike-light-switch

If you’re going to use your bicycle as transportation at night you really must have a head and tail light in hopes that the crazy drivers don’t hit you. For good reason, these lights don’t turn themselves off. But [Miceuz] kept forgetting to shut it down upon arrival and always ended up with dead batteries. His quest for an auto-off feature that actually worked ended in a brilliant and simple add-on circuit.

He first thought about using an accelerometer, but couldn’t find one that fit the bill without also adding a microcontroller. He came up with an even simpler circuit, which can be seen at the base of the black plastic housing. It’s a bit of copper clad board with a small spring attached. The spring completes an RC timer circuit which drives a MOSFET. When that circuit is charged, the MOSFET connects power to the bike light. When the cap runs out the MOSFET threshold cuts power and everything turns off. Since the spring jiggles while he rides it provides the momentary connection necessary to charge the capacitor. Stay stationary for about 30 seconds and the auto-off kicks in.

Home automation hack controls lights based on head count

This home automation hardware turns on and off the lights based on room occupancy. The hack is an extension of an earlier version that was only a proof of concept. [RPisces] took the idea and made it into reality by mounting the sensor hardware in a doorway.

He prototyped the device using the MSP430 launchpad. It monitors a pair of IR distance sensors which record a change when something passes between them and the opposite side of the hallway. This is a good sensor choice as it only requires hardware on one side of the passageway. Because two of them are used, it’s quite simple to figure out if a person is entering or leaving the room based on which is tripped first.

In this case [RPisces] drives a relay to switch a lamp on and off. But it could be used for just about anything. We’d enjoy seeing it trigger an audio system like the one [Quinn's] installing in every room.