[robocup-humanoid] Decision About Teen/AdultSize Balls

[Oskar von Stryk]

Dear AdultSize and TeenSize Teams Qualified for RoboCup 2010 in Singapore,

About three weeks a ago we had a discussion on the mailing list
http://lists.cc.gatech.edu/pipermail/robocup-humanoid/2010/thread.html
about the ball for 2010 because the current orange beach handball
is not equally well available all over the world.

Last year we had been using an
 	Orange beach handball, size 2 (18.0cm diameter, 294g).
This ball seems not be available easily worldwide and also
deforms strongly during a tournament and then does not roll
straight very well.

Sven Behnke suggested to use for the AdultSize
         orange FIFA standard size 5 football
which I think is a very good idea.
FIFA standard size footballs are available all over the world.

However, Sven suggested to keep the orange beach handball for
TeenSize because higher weight of the FIFA-Ball size 5 could be 
problematic for lightweight TeenSize robots and
the size relative to the robot would be too large.

I looked up the specification of the standard size footballs
(outdoor, "FIFA inspected", at ball pressure 0.8 bar)
cf. http://footballs.fifa.com/Football-Tests:
- Ball size 5: weight 420-450g, circumference 68-70cm
- Ball size 4: weight 350-390g, circumference 63.5-66cm
- Ball size 3 (data was not from FIFA web page):
 	weight 320-370g, circumference 62cm

Current beach handball:
- size 2: weight 294g, circumference 56.5cm (18.0cm diameter)

Orange soccer balls size 5 and size 3 seem to be available worldwide.
The middle also size uses an orange FIFA ball size 5.

Therefore I would like to ask the 6 AdultSize and 4 TeenSize teams
about their opinion and vote about the ball to be used in RoboCup 2010 in 
Singapore:

1) AdultSize teams:
 	+ Proposed ball: orange FIFA ball size 5
 	Alternative balls:
 	+ orange FIFA ball size 3
 	+ orange beach handball

2) TeenSize teams:
 	+ orange FIFA ball size 3
 	+ orange beach handball

Please send your vote not later than *** May 1st ***.

With best regards,
Oskar von Stryk