Baby’s first star light projector and a foil slip ring

For a newborn, everything is magical; a lack of object permanence means everything is new, wonderful, and novel. What then, could be better than a projected star field circling an infant’s room, gently sending them to sleep?

[Pete] was inspired by this earlier starlight projector that projects a rotating star field onto the walls and ceiling of a nursery. Instead of a rather loud servo, [Pete] used a quiet 12 Volt gear motor that spins the star field at 5 RPM. Like the previous build, a LED was used but [Pete] found a color-changing RGB LED that automatically shifts colors.

The shaft of [Pete]‘s gear motor is tiny, and unlike the servo, there’s constant rotation. This meant a slip ring was needed to pass electricity into the spinning sphere. A piece of copper foil and a pair of improvised brushes served just fine. While [Pete]‘s project, like its predecessor, doesn’t seem to have any recognized constellations drilled into the sphere, the foil slip ring opens up the possibility for a small microcontroller being fitted inside the globe with blinking lights.

Check out the video of [Pete]‘s build in action after the break.
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Bringing the stars to your baby

[Zach] saw a stuffed animal that projected some simple stars on the ceiling. This gave him an idea that he could build a tiny star projector for his 3 month old daughter’s room.  The idea is to put an LED inside a ping pong ball with tiny holes and rotate it slowly.

The electronics are fairly strait forward. He’s using an MSP430 to control the servo and LED, allowing him to set different speeds and turn the whole thing off after a certain amount of time.  The ball took a little bit of trial and error though. He first started by drilling some holes, but found this to give poor results. The holes were just too big. He finally ended up heating up a  sewing needle and melting tiny holes in the ping pong ball. That worked perfect.

After the break you can see a video of it moving. The servo is pretty loud, which might actually be a good distraction for a 3month old, but might be something to address in the future.

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