CNC Light Painting

February 11, 2012 By Leave a Comment

Light painting is a technique where a shape is drawn with a light source while a camera is taking a very long exposure shot of it. To do this well by hand would take a lot of skill, so I naturally decided to make my “light art” with a CNC router.

Using this technique, the LED light is treated just like an engraving bit would be under normal circumstances. The difference is that the Y axis is swapped with the Z axis allowing for easy movement in the plane that you see displayed in the picture above. This allows the old Y axis to switch the light on and off in the same way that an engraving bit is lifted to stop engraving and lowered to start (explained here). Instead of a bit though, it’s a switch.

Be sure to check out the video of the router in action (with the lights on) after the break: [Read more…]

Filed Under: cnc hacks, digital cameras hacks Tagged With: , , , , ,

Plotting pictures with light

February 11, 2012 By Leave a Comment

Flashing LEDs for a persistence of vision display are on bicycle wheels, alarm clocks, and even light painting sticks to draw images in the air. What if you wanted to plot an image in the air (translation) with a single LED? That’s what [acorv] did after taking a cue from a polar plotter.

Like the polar plotter and Drawbot, [acorv]’s build began with a pair of stepper motors and fishing line (translation). [acorv]’s brother upped the stakes a bit and suggested replacing the marker with an LED and taking long exposure photographs. Armed with a DSLR and a lot of patience, a few experimental pics were taken. To plot the image, the Lightbot flashes its LED as it goes across the plot area. The process of building an image pixel by pixel takes a while – eight minutes for this image – but the brothers were encouraged enough to take their rig outside.

After setting up the polar plotter between two tripods, [acorv] and his brother made this image in the dead of night. It’s an interesting spin on the POV LED builds we’ve seen before. Check out [acorv]’s Lightbot slowly drawing something after the break.

[Read more…]

Filed Under: led hacks Tagged With: , , ,

Color sensor gives the RGB values of anything

February 7, 2012 By Leave a Comment

[Rick Osgood] wanted to build a color sensor that could be held up to any object to get RGB color values. He originally started with a photoresistor and a few LEDs, but couldn’t get that to work reliably. [Rick] finally completed his color sensor after finding a digital luminosity sensor on Adafruit, ending up with a pretty accurate piece of hardware to judge the color of something.

The idea behind the color sensor is to light up red, green, and blue LEDs and see how much light is reflected back from the object with a luminosity sensor. [Rick] chose an Arduino to do all the heavy lifting for the light sensor and activating the LEDs.

After a few tests [Rick] got his color sensor working, but it’s not up to par with what he had expected. This isn’t really a problem: the LEDs probably don’t have the same brightness and the luminosity sensor doesn’t respond evenly across the entire rainbow. Those things can always be fixed in software, though. It’s a nice project that could serve as part of a prototype for this color picker pen.

Filed Under: hardware, led hacks Tagged With: ,

Office game show buzzer keeps things fair and square

February 3, 2012 By Leave a Comment

office-game-show-buzzer

The sales team in [Chuck’s] office is a pretty competitive bunch as you might expect, and they decided that they wanted a system which would allow them to challenge one another during their weekly meetings. The competition involves answering questions posed by their manager, but hand raising only works for so long – they needed a definitive way to tell who “buzzed in” to answer a question first.

Since [Chuck] only had a short bit of time and a tiny budget to work on, he opted to find the easiest solution to the problem, which was an Arduino-based game show buzzer system. The game display is built from an Arduino, some LEDs and an Altoids tin, while the buzzer pushbuttons were salvaged from an old radio broadcast console.

Now, when a question is posed, the salesman can buzz in to answer, knowing that only the quickest person’s button click will be registered. When it’s time for another question, the host simply clicks his buzzer to reset the console.

While it’s not quite as fancy as this game buzzer system we featured a while back, [Chuck] says it does the job perfectly and was cheap to boot.

Continue reading to see a short video of the office game buzzer system in action.

[Read more…]

Filed Under: arduino hacks Tagged With: , , , ,
Newer Posts »