Alex’s Mobile

I wanted to make a mobile for my son Alex, as most mobiles I’ve seen look fantastic from the top where the parents are (i.e. the ones buying the mobile!), but from underneath are boring.

So I decided this one would be different, and I would be able to upgrade it as he ages.

It will involve RGB LEDs colour cycling, driven by an Arduino (well Atmega128/328 microprocessor anyway).

It will also have two controls initially:

  1. Timing control to control the speed of the colour cycling.
  2. Max brightness control (self explanatory?)

The idea is that this mobile will be self contained, and capable of running from a single 9v or 4x AA batteries, or from a wall wart, and be light enough to hang safely about a cot or crib.

Update 5th Dec 2009:

Have a working Arduino circuit using 74HC595 shift registers to control the individual colours on single LEDs.

Will try and post a circuit diagram shortly.

Update 14th Dec 2009:

Here is the circuit breadboard for the current design:

Alex's RGB LED mobile breadboard layout

Update 7th Jan 2010:

Managed to source some balsa wood and new craft knives to make a mobile spine. Want something less boring that just a straight dowel with things hanging.

Update 14th Jan 2010:

I came up with something less boring after a Yahoo! image search browsing session, and completed the 3D draft designs for Alex’s Mobile and here’s what I have so far.

LEDs will be positioned upwards onto the platter above to reflect light downwards, spreading the light over the different platters, in a hopefully interesting pattern.


Above is the view looking up at the mobile.


View from front, one perspective.


View from front, different perspective.

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