[robocup-small] Ideas for 2007 Rules

[Tim Laue]

Hi RoboCuppers!

Here are my personal thoughts on possible rule changes:

a) Referee
I think the implementation of an Ethernet-based communication is a very
good idea.
At RoboCup 2006, Plasma-Z demonstrated a semi-autonomous referee. We are
currently working on an autonomous referee system. Maybe some other
teams are also preparing referee programs (that would be nice to know!).
This is a nice research topic and also - due to the high speed of Small
Size matches - something very useful to have. Therefore I would suggest
something like "If both teams agree, the human referee may be supported
by a referee program" for the 2007 rules. For me, this seems to be a
reasonable step in this direction. During RoboCup 2007, regional
competitions, or friendly matches we might gather experiences which will
help to decide on the full use of this kind of technology.


b) Number of Robots
In general, I would like to have more robots per team, but not on the
current field (c.f. next paragraph). In addition, I have some
suggestions which might prevent the field from becoming too overcrowded
(c.f. paragraph d).
In 2007, six robots per team might be possible.


c) Field
We have now the same field size for three years. We should start to
enlarge the field now. Many teams argue that lab space is a problem. Of
course it is. But for practice, you do not need a full field for most
things. I doubt that there are many Middle Size teams who have a full
field in their labs. Due to the global vision setup, it is quite easy to
practice on smaller fields.
A much harder problem will be the setup of global vision systems during 
a competition. Currently, most teams have two cameras above the field. 
Its already hard to make a reasonable schedule that contains many 
matches as well as enough time for teams to set up and calibrate their 
systems. Having a field that requires every team to set up four or more 
cameras will make competitions with 20 or more teams unrealizable, in my 
eyes. For future competitions (2008 and later) with possibly quite large 
fields, this issue should be discussed soon. For 2007, I think we have 
two choices for enlarging the field:
* We double the field size and limit the number of cameras per team to 
two or three. The FU-Fighters already demonstrated that it is possible 
to double the field size and still use two cameras. That seemed to work 
fine with their system. Did any other team try to do something like that 
with their own system?
* If such a change is too radical for most teams, we could do it in 2008 
but decide that this year. For 2007, we could do an increase of the 
field size of 50%. I expect that after such a change, most team's 
software would still work in general (despite some minor adjustments, of 
course ;-).

And now for something completely different: I like the idea of having 
goals which look like real soccer goals. But I fear, that it might be 
quite difficult to build goals that survive hard shots or misbehaving 
robots.


d) Fouls
I do not like the current rules concerning yellow and red cards. In 
practice, most teams break some rules (not intentionally) but referees 
hesitate to show cards (I don't know, if there have been any cards shown 
during RoboCup 2006). That's not because they are too shy. But since 
"The number of robots on the team is reduced by one after every two 
yellow cards." (c.f. Rules 2006, Sect. 12), showing yellow cards might 
become a very hard sanction.
I would suggest to have more temporary removals (e.g. for 2 minutes) of 
robots, if they commit minor fouls (e.g. fail to respect required 
distances). This could be done independently of any cards. Currently, it 
is often tolerated that a robot repeatedly interrupts the execution of 
the opponents's throw-in, e.g. by trying to play the ball before the 
throw-in has been executed. That is not nice to watch. I would like to 
remove exactly that robot for some time after its first foul. Maybe such 
a penalty could be reduced, if the robot is capable of driving to a 
certain position where a robot handler could pick it up.
In my eyes, the application of more temporary removals would
a) force all teams to take more care of implementing all rules and
b) make the field less overcrowded (in case there are many fouls)
c) lead to varying team sizes which might be quite interesting from a 
tactical point of view.


e) Ball / Restriction of Kicking Speed
Changing to a ball that is not as standardized as current golf balls are 
(e.g. the beach tennis ball on the video) could lead to an end of the 
arms race since spending much time and ressources on kicker tuning does 
not guarantee any success, if a slightly different ball is used during a 
competition.
If we keep the golf ball, I would suggest to have a certain speed limit. 
Since we currently do not have any referee application that checks the 
compliance with the rules, we have to trust in a kind of gentleman's 
agreement. I would not have any problems with that. To enforce such an 
agreement, we could allow a video evidence (only for this kind of 
decision!) after a match. A team that breaks the speed limit might be 
penalized then (disqualification, loss of points, ...).


f) Offside
Some kind of offside rule would be nice. But currently, most teams play 
with one or more dedicated defenders. I do not expect any "classic" 
offside situations. Maybe a redesign of the penalty area (e.g. much 
larger and rectangular) or some other rule changes make this topic 
become more interesting.


Any comments?

Best regards,

Tim

------------------------------------------------------------
Dipl.-Inf. Tim Laue                 Courier Mail Address:
FB3 Mathematik - Informatik         Cartesium 0.057
Universität Bremen                  FB3
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