It was designed by our friends at Danenberg Design (who have retired recently) and fabricated in San Jose, CA. Here's an excerpt from a story about this project:
"Asian spas have shade shelters made out of bamboo and tied weeds," Danenberg says. This is the effect he was trying to recreate with the undulating stainless-steel canopy for the master bath ceiling that he designed and Nevarez Machinery in San Jose fabricated. The details extend to the end of the metal tubes, which resemble the end of a bamboo reed.
Here's the link to the story:
http://www.paloaltoonline.com/news/show_story.php?id=17595
:) Rhoda