[robocup-small] Proposal for energy budget

[Beng Kiat Ng]

Hi all!

Here's my crude proposal to introduce a energy budget constraint to SSL.
It's an old idea that some of us has thought of before, and I have put it
into something more concrete to get the rest of the community thinking
about it. If theres' enough support, I hope to have this in place in 2007,
maybe even 2006.

First of all. I believe having an energy budget make the game more
interesting. This is another research area that teams can work on. If you
think about it, energy constraint is in every kind of competition, be it
human soccer, F1 racing etc. In fact, if we lengthen the games to 1 hour,
almost all teams would face the constraint (assuming they are not allowed
to change batteries).

My proposal is based on a quick calculation based on my robot, which is
among the lightest in the league.
My robot weight is 1.45kg. It's battery supply comprises 5 cell
Li-Polymer1050mAh in series. Currently, our robot is able to play about 35
minutes continuously. 5 cell of Li-polymer is equivalent to 15 cells Ni-Mh.
Currently, AAA cells Ni-Mh is about 1000mAh in capacity. My proposal is to
restrict each robot to about 8 (maybe less, 6) cells of AAA Ni-Mh
batteries. THis is based on the fact that most robots are heavier than 1.5
kg and thus would not have enough energy to run top speed for 20 minutes.
Moreover, Ni-Mh batteries would not be able to source very high current,
and thus limit the top speed indirectly.

Robots would be limited to 1 set of batteries per game. There would be
limited number of substitution robots, maybe not more than 2. Some kind of
holding area for robots can be used to make sure that no teams can change
the batteries during games or half time.

When robot's energy is limited and speed lowered, it's reach would be
smaller and we would not need a bigger field!

Some teams believe there's no need to limit robot speed or ball speed. I
beg to differ. Unless we are into some kind of speed game, like the F1, we
should constantly try to limit them. The thing is that the robot speed and
kick speed is a critical factor in the outcome of the game. There's no way
a group of kids below 10 can beat a young adult group simply because they
are are not as fast and powerful (let's ignore the height difference). If
we do not limit, robot speed & ball speed can easily double, especially
when the field gets bigger. If we limit the speed to something easily
achieveable, it levels the playing field. Hardware investment need not be
so expensive, which means SSL can again be an affordable entry league.

Regards
BengKiat