[robocup-small] Rule changes in SSL

[Jacky Baltes (Hansjorg)]

Hi,

I have argued against dribble bars for a long time.

the myth that you can not pass without a dribble bar is propagated 
year after year as well. In short it depends on what you define 
REALLY receiving a pass means.

1.) I saw CMU score after a pass in '98. According to the Big Red crowd,
the CMU robot did not REALLY receive a pass, but rather robot1 pushed it
away from the goalie and robot2 drove through and scored. We also had
code that made those types of passes as did many other teams.

2.) A lot of passes in human and robotic soccer should actually be into
empty space. The ball is shot into an area where you know your team mate
will run to faster than the opposition. By the time your opponent
reaches the ball it has lost a lot of velocity. This is a big part of human
soccer. This is hard to do on a small field but ther larger field will
provide more empty space. In this case, it does not matter if you have a
dribble bar or not.

3.) I can roll a ball at 2 m/s at our robot, it will hit the robot and
come to rest within 5 - 10cm of the robot. I consider this receiving a
pass.

4.) What I can not do without dribble bars is shoot a ball at a robot at
high speed and then the ball sticks to the robot. This is also
impossible in human soccer. Even the best players can not receive a ball
that is kicked at full force at them when they are too close to the ball.
Instead, they have to redirect it to some open area and run after it.
The shoot and stick is more reminiscent of ice hockey.

2.) and 3.) however are close to what happens in human soccer and I
would consider those receiving a pass. I believe that implementing these
type of passes and defenses against them is an interesting research
topic.

So please, stop claiming that one must have a dribble bar to receive a
pass or that teams without dribble bars do not implement passing, unless 
you use your narrow definition of REALLY receiving a pass.

CU,
	Jacky
	

On Sun, Nov 14, 2004 at 05:43:02PM -0600, Will Stokes wrote:
> > I disagree - Passing has nothing to do with a dribbler.
> 
> I'm not an active participant in RoboCup any more, but on this subject I
> feel I must speak up. Without a horizontal dribbling surface, it is almost
> impossible to receive passes in the SSL. No one really received a pass
> before 2000 when Cornell placed horizontal dribblers on their robots. 
> Without a dribbling surface, the best a robot can do is to reflect the
> ball either toward another fellow robot or the opponents goal.
> We're trying to play soccer here, not pool/billiards. For the moment,
> IMHO, dribblers have EVERYTHING to do with passing.
>    ________________________________________
>   /                                        \
>  | Will Stokes  - wstokes (at) gmail.com    |
>  | Album Shaper - http://albumshaper.sf.net |
>   \________________________________________/
> 
> _______________________________________________
> robocup-small mailing list
> robocup-small at cc.gatech.edu
> https://mailman.cc.gatech.edu/mailman/listinfo/robocup-small