Laser Light Show wall clock

The most ridulous wall clock ever... 


This page was featured on on 18-June-2006.  Yay.  Google Pages has decided though that we're using too much bandwidth.

Andy with bandwidth from, MB, and H3PO have been so kind as to mirror my files.  Thank you all very much.  I've also posted the files on flickr and youtube.

Just a test

I wanted a simple application to test my pusle width modulator/servo controller circuit, and so I built a robotic arm with two degrees of freedom.   

I used cheap ten dollar servos, and took a jigsaw to scrap wood for the mechanics.  To check the accuracy of it, I fastened a cheap laser pointer onto the arm, and wrote some software to control it.  This will ultimately lead into my sentry gun project.

To test the repeatability of the positioning, I made a poster on the wall with 14 circles: "Hour", "Minute", "AM", "PM" and the digits zero through nine.  I calibrated the arm to point the laser pointer at each of these circles by manually moving until the laser pointer was right, and then recording the positions.  

I then wrote a simple program (clock.tar.bz2) on my laptop to send the right signals down the parallel port, and blazao, it tells time.

Since it can only illuminate one figure at a time, I programed to point to each of the figures in a sequence.  For 3:24 pm, it points to: "Hour", 3, "PM", "Minute" 2, 4.  It spends one second on each figure, and then moves on, and loops at the end.  The servo motors even make a nice ticking noise once a second.  Here is a 4 MiB video in mpg; sorry it's rotated 90 degrees. [mirrors: Andy/Seanet, MBH3PO, youtube].

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