Rovers are bugs that interact with architecture. Projector organ reflects the sunlight and produces mirroring on the objects, walls, ceilings that moves around slowly as it keeps a time. It is like a sun dial, but it has its own time. They play music, note by note spaced out for few seconds to few minutes depends on the amount of the sun it gets. It suspends the note let the song linger, creating a space to dwell on.