pic: VEX Solar Tracker Gearbox

[Nick Lawrence]

Originally Posted by Chris is me

Nick, I told you to keep our arm gearbox a secret!

I didn't get the memo. I guess we better tell them the amazing feat of our arm working with the sun to destroy the competition...

Originally Posted by billbo911

Why do you need that much reduction?

Let's see, the Vex motors run at up to approx. 100rpm. The sun revolves around the earth at almost exactly 1rpd. (In fact, it is so close that the error is negligible for this application.)
So, 100rpm * 60 * 24 = 144000rpd

That is way too fast for a "Solar Tracker".

Now based on the photo, Your reduction is: 800.33/1
((84/12)^3)*(84/36))
So now your output shaft is running near 180rpd at full speed.

Using some simple control logic, you now have a very controllable solar tracking system.
May I ask what you are using to sense the position of the sun?

The idea was to make it "follow" the sun, rather than track it and adjust accordingly. This gearbox relies on the VEX motor shown to run at 5 rotations per minute. Will it? Who knows. It was never built to fully function, just to prove the concept. However, I would love to fine tune it and make it work next September, when class resumes.

This project was for a final project for my robotics class.

-Nick