Instructables

Arduino Analog Hard Drive POV Clock

Picture of Arduino Analog Hard Drive POV Clock
Inside Clock.jpg
Remote Front.jpg
Remote Side.jpg
Chronotdot & ULN2803.jpg
Molex Power.jpg
2011-08-04 15.44.03.jpg
2011-08-04 15.44.22.jpg
This work is based off the work of two other individuals that did an excellent job of paving the way for my project. 

Author:vishnubob
http://www.instructables.com/id/Hard-Drive-Persistence-of-Vision-HDPOV/

His work was based off Ian Smiths version of the same type of clock.
http://www.ian.org/HD-Clock/



Using vishnubob’s instructable I began creating a Hard Drive POV clock.  Once I had the basic design completed I ran into a few things that I wanted to change.  The first was that the platter rotated at 7500RPM & with a slit cut into the aluminum platter it made a good deal of noise.  The second thing was a python script running on the PC provided the time to the arduino, I wanted something that is standalone.

What I did to solve the speed problem I used a 3-Phase ESC connected to an arduino, the program maps the potentiometer value to a value between 0 & 180.  Using the servo library I can then send that value to the ESC to control the hard drive rotation speed.  This helped a good deal with the noise & made it easier to have on next to me.

I used a chronodot real-time clock to store the time & date, the unit also has the ability to report temperature. To set the time I use another arduino with a touchshield & xbee Bluetooth module.  There is a corresponding xbee inside the clock so you are able to update the time wirelessly.  Recently I added background color updating to predefined colors cyan yellow & magenta.  The reason for defining the colors is for simplicity & the fact that RGB are already used for the hands of the clock. On the remote there is also an option to switch to a temperature display. This polls the chronodot for the tempature then displays it in 25 degree increments.  So for 80 degrees Fahrenheit there would be three full pie slices & a small portion of a fourth to represent 80.
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rimar20002 years ago
The video shows a nice work, but if you draw the numbers on the clock, it would be far better. At first I didn't understand it, because I waited a "digital-digital" clock.
drawing numbers isnt possible on this because the leds are mounted on the circumference.
Yes, I admit it is nice. Maybe you could write the numbers around, to facilitate the reading.
I think it looks great without the numbers...real sleek and sexy.