In progress... This is the idea, and some of the design for a new project called the Rain Light(?) or Monsoon Lamp(?). A PIR sensor placed in the center section of the plexiglass will trigger numerous lasers to illuminate the floor as falling drops of rain, coupled with voltage in corresponding piezo elements which will create the sound. The structure is derived from a Penrose aperiodic tile which means this is only the basic structure from a much larger repetitive form. Each core pattern will be driven by an Arduino, either UNO or MEGA (TBD). The choice of this form is purely for the visual appeal, though the 'kites' and 'darts' underlie the formation of this variety.
The images include, a concept graphic, the schematics for the PCBs, acrylic laser cuts for the proto, and the pattern assembled in repetition. The PCB took some time to design. Currently, I am on the four revision. At the heart is a 1amp LM2575 switching regulator, dropping from the 12volt power supply. After noodling with other regulators, I am much happier with the steady supply and relatively cool operation of the LM2575. Really, the only way to go. This one has a 330uH fixed core to provide about 1 amp. Still having a stock of 595 shift registers, guess you can figure out what the other ICs are. Big thanks to the folks at RayLogic for their kind advisement.