Laser Cutting Orreries

An orrery is a clockwork model of the solar system, demonstrating the machinations of the planets traveling around the sun in a sublime pattern of epicycles. A tellurion is a subset of the orrery, showing the rotation of the Earth around the sun, and the orbit of the moon around the Earth. [HuidongT] created his own tellurion out of laser-cut parts and just a few bits of copper tubes and bearings.

This project was originally inspired by the holzmechanik, a tellurion constructed from plywood gears and brass tube. [HuidongT] saw a few shortcomings in this project: the Earth didn’t spin and the moon didn’t orbit with its natural five-degree inclination. [Huidong]’s tellurion would have these features and include an illuminated sun, demonstrate the change of the seasons, and show lunar and solar eclipses.

While there was a bit of math involved in figuring out the gearing, it’s not much: the Earth would go around the sun every 365.25 days, the moon would go around the Earth every 27.32 days, and there is a difference between sidereal and solar time. A quick script made quick work of the math, and anyone can easily find tools to create gears given a diameter and the number of teeth.

The fabrication of this tellurion was made with acrylic on a laser cutter with a handful of 3D printed parts. The electronics are simple enough — just a motor and a few LEDs, and the completed project works well enough. You can check out a video of the tellurium below.

12 thoughts on “Laser Cutting Orreries

  1. whoah, that’s a lot of gears! The wobble is distracting but i’ve watched it a few times to see the phases of the moon and the seasons change. I can see myself doing this with half spheres and no automation just to play with it. Tack up post-its on the walls around me for the “fixed” stars and constellations.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s