I found this while looking at odd news at Reuters. I remember as a child that in America there were roads that made a certain rhythmic sound as you
went over them. This road hums and is more harmonic.
The Japanese culture comes up with some of the coolest things. That's pretty cool, but the tune only last 13 seconds, not worth the effort really,
especially since most drivers probably have music going in their cars anyways. Still fascinating though.
This would be especially useful to counter the problem of newer hybrid and electric vehicles being too quiet for pedestrians to hear. It's
definitely better than playing recorded engine sounds as some have suggested.
We have those grid marks on the shoulder side of the road to 'wake up people nodding off. Some grids are located just before a stop sign or major
intersection. It's a warning beacon of some sorts.
The engineering concept reminds me of those old time Music Box Cylinders, except on
a bigger scale.