Solar tracking sundial with three hands

Here are some archive photos from my former  solar tracking sun dial project.

Prototype

The driving mechanism was built from old children toys. As a time dial serves a small table clock.
Some Lego parts were used to clutch it into a 24 teeth worm gear which again was made of some BILO parts. Between the motor and the worm gear there is still a 1:3 gear and a 1:20 Lego gearbox.

25.02.2010 First time in outdoors

Tracker sensors - XOB17 solar cells

Panels W and E are used to track, panel S senses, if  sun is shining. If not, tracking is stopped.

Voltage compararor LT1017  drives the motor forward, if the  sensor W voltage > E.
Manual switch is used to drive the motor backwards.

Final version

Final version 2012.01.25

Driving mechanism

Clock dial connection

Original clips of the YouTube video

Clip 1   Clip 2   Clip 3   Clip 4   Clip 5   Clip 6