Good Project (Score 2, Informative)

I just graduated from NCSU's aero department (www.mae.ncsu.edu) with these guys- I did the aeronautical design project, but the Tumbleweed project turned out alot better than I expected. From what I heard, the guys at NASA were much more enthusiastic and receptive to their design than previous years' projects (a mars balloon, among others).

As far as steering, several options I remember hearing their team members discuss throughout the year were actuating the planar sails on the inside of the carbon fiber ribs, some sort of anchor for times when prevailing winds were in unfavorable directions, and changing the mass distribution and inertial characteristics. However, I think the point is that they wanted a simple, lightweight, easily reproducible design; the whole idea of a tumbleweed is based on utilizing what you don't have to bring along (interestingly enough, it was first thought of when a test rovers wheel blew away and escaped the crew out in the desert, I believe).

I remember their presentations mentioning research they did on the atmosphere and typical wind climate, average surface qualities (rock size, etc), and how it would affect their design. The biggest concern I heard judges from industry at the southeast AIAA student conference (http://www.AIAAstudentconference.org) echo was over oddly shaped debris gathering inside the design and weighing it down.

The pictures you see on their website are from the senior design picnic less than a month ago. The actual design is even larger. The wind was calm, but it would only take about a 10 knot gust to start rolling. And yes, the girls in the pictures are real engineering students, and I know them all- don't worry, they're a lot smarter than to let you guys explore any surfaces. But I'll let them know you brought it up. Also, Dustin isn't copping a feel. I think his family was a few yards outside that picture, but it does look sort of funny.

If anyones curious, look up our design project too (http://www.mae.ncsu.edu/courses/Mae478-479/team3/ webpage/frameset.htm) on a hopefully soon-to-be autonomous 200 knot jet aircraft (pretty decent for ~12 lb. thrust). The section pages are still empty, but there are lots of pictures and a couple videos.