[robocup-small] [Fwd: Rule changes for 2005, Commends from Cornell University]

[Brett Browning]

The following mail is from Raffaelo D'Andrea from Cornell University:
------------------

To: robocup-small at cc.gatech.edu
From: Raffaello D'Andrea <raff.d'andrea at cornell.edu
Subject: Rule changes for 2005, Commends from Cornell University

Dear Small Size League,

Please find our comments below.  These include feedback on Raul's proposal.
Raul, thanks for the in-depth and well written document.

Change 1:

The dribbling distance will be set at 500mm for both active and passive
dribblers.

We feel that we should simply eliminate the distance requirement.  Dribblers
only became a potential problem when Cornell developed side dribblers. 
Horizontal
dribblers are a great way to obtain some control of the ball, but they 
are limited
in effect.  In particular, they are really only useful for getting 
control of a ball and receiving
a pass. In 2003, when I was part of the rules committee, there were actually
three groups that felt we should simply ban the side dribblers, and only 
allow horizontal
dribblers: Lucky Star, RoboRoos, and BigRed.

For those that want to see what the game is like with only horizontal 
dribblers, look
at the video footage from 2000 and 2001 (we actually had vertical 
dribblers in 2001, but
they were worse than useless.  They need to be at an angle to be 
effective).   The footage
speaks for itself: we haven't come close to that level of passing since 
that time.  If the field
had been larger in 2001, the passing game would have been outstanding.

Our recommendation:  allow horizontal dribblers, ban all non-horizontal, 
moving dribbling surfaces.
Simple, and to the point.


Change 2:

For all restarts where the ball has gone out of bounds and the rules
state the ball is too be placed ON a boundary line or within 10cm of a
boundary line, the ball will be instead moved towards the middle of the
field to an imaginary line that is 10cm any of the boundary lines that
the ball is within the 10cm wall.  Needs rewording but I think it makes
sense.

Reintroduce the 2003 walls.  They worked extremely well.  Getting rid of 
the sloped
walls was a huge mistake.  More on this later.



Change 4:

No more bluetooth is allowed in the small-size league, and all other RF
decisions will be left to the OC based on local conditions.

Seems like an arbitrary decision.  What is the motivation?


Change 6:

The EC/OC/TC will decide upon ALL yellows, blues, greens, cyans, and
pinks allowed to be used by robots before the competition and will make
enough of these colors available at the competition for each team to
field 6 robots.

What for?  Is this really a problem?


Change 7:

We will have 6 robots per team

Again, where did this change come from?  See comments at the end.


Change 9:

There will be no chip kicks allowed during any restart.  Chip kicks (of
any height) will be allowed during all other situations.

With regards to chip kicks.  I'm really addressing Raul's comments:
We should simply enforce the 20 percent convexity rule.  I was not at the
competition in 2004, but I was told that there were some teams that were 
blatantly violating this rule.
Scooping the ball up violates the 20 percent rule.  Chip kicking
can be achieved without violating the 20 percent rule.  For
example, the RoboDragons in 2003 had an excellent chip kicker.  Also 
note, however,
that it is not trivial to design a robust chip kicker.  It takes away 
from other design
choices, such as faster,  more maneuverable robots.  There is a tradeoff 
involved.

Addressing Sean's proposal. The rule could be the following:  treat all 
restarts, with the exception
of penalty shots, as an indirect free kick, with the caveat that the 
indirection
must come from your own team. In other words, the ball must touch
at least one other robot on your own team before going into the net.

Overall comments:
----------------------
1) There were too many changes in one year.  The only major changes in 
2004 should
have been to make the field larger and to ban side dribblers.    This is 
what we should
be doing for 2005.  We tried radical changes in 2004.  They did not 
work.  I think that
we will be in a much better position to address Raul's comments once we 
can see
what incremental changes lead to.   But I will comment on one of Raul's 
proposals:
battery/energy constraints:

2) Our game is much closer to hockey than it is to soccer. Or indoor 
soccer.   And in hockey,
there are no such constraints:  the players go on,
skate really hard for 2 minutes, and then take a rest for 3 to 5 
minutes.  They go all out when
they are on the ice. While I agree that putting energy constraints would 
make the problem interesting, it sounds too
complicated and unnatural, and is something that should be tackled in 
the simulation league, not a
hardware league.  Adding energy constraints will push the design space 
to lightweight, expensive
materials.  The robots will become much more expensive. Imagine what 
imposing the no-substitution
rule would have on hockey...

3) In principle, I think that the automated referee is a great idea.  In 
2001, we developed
our own competition, with real robots, to explore control of autonomous 
vehicles in uncertain
and dynamic environments:  RoboFlag.  For those interested, have a look at
http://roboflag.mae.cornell.edu/  In RoboFlag, there is no human 
referee.  It was
actually quite difficult to develop a set of rules that allowed 
human-free arbitration.
In RoboCup, we should work our way slowly towards this goal, with 
demonstrations
from several teams that want to take the lead.


*****************************************
   Prof. Raffaello D'Andrea
   101 Rhodes Hall
   Sibley School of Mech. & Aero. Engr.
   Cornell University
   Ithaca, NY 14853-7501
   http://www.mae.cornell.edu/Raff
   (607) 255-0710 (Voice)
   (607) 255-1222 (FAX)
*****************************************


*****************************************
   Prof. Raffaello D'Andrea
   101 Rhodes Hall
   Sibley School of Mech. & Aero. Engr.
   Cornell University
   Ithaca, NY 14853-7501
   http://www.mae.cornell.edu/Raff
   (607) 255-0710 (Voice)
   (607) 255-1222 (FAX)
*****************************************