[robocup-small] Proposal for energy budget

[Beng Kiat Ng]

Hi Steffen!

The whole point of using the small batteries is not just to limit the
number of times robots can run up and down the field. I also want the
robots to slow down. Your robot just cannot run at 20volt and 4A anymore.
You have to lower the top speed and acceleration.

Giving extra energy to heavier robot is going to be difficult to implement.
I rather specify a practical minimum robot weight. As for higher power CPU
and more sensors etc, well you just have to cut them down. I think if we
were to make our robots simpler and lower cost, then the SSL can once again
claim to be a low cost entry league for RoboCup. In this way, we can stay
relevant for a longer time.

I also in favour of having a separate unlimited battery source for
non-actuator (CPU, sensor etc) use only. But I think it would be quite
difficult to enforce.

Regards
BengKiat



                                                                           
             Steffen Prüter                                                
             <mail at steffenp.de                                             
             >                                                          To 
             Sent by:                  robocup-small at cc.gatech.edu         
             robocup-small-bou                                          cc 
             nces at cc.gatech.ed                                             
             u                                                     Subject 
                                       Re: [robocup-small] Proposal for    
                                       energy budget                       
             15/09/05 04:06 PM                                             
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           




Hi all,

we support a energy budget for the SSL but to restrict the batteries is
the wrong way.

Beng Kiat Ng wrote:
 > Some said current robots cannot be used with this proposal. Well, I
think
 > only a slight modification is needed. You need a DC-DC converter. If you
 > need 12 volts, use converter to step up the voltage. For teams using a
 > power hungry board, they will be disadvantaged. Motors need not be
changed
 > unless you want better performance like using a lower voltage motor.
 > Remember, it's going to draw more current.

You cannot use DC-DC converter for the big motor current. Except, the DC-DC
converter is the biggest component on the robot. Example: We need a peak
current of 4 ampere at 20V. That means we need an 80W DC-DC converter.
Doing
a quick INet search, i found some converters with an effectiveness of about
75% and with heat sink elements they have a size of 5x5cm. Limited
batteries
will be a handicap for all teams because they need these converters.

Also, we think that it is not the aim of the SSL to build lightweight
robots. We want to add more intelligence directly on the robot so we
need more sensors and bigger microcontrollers and our robots will be
heavier.
Our limit is the diameter and the height of the robot and that is already
restricted in the SSL rules.

At the moment, we have an extra module that measures the current and the
voltage that our robots use. With this, we can calculate the used energy
of every robot. This is a way to check the used energy in SSL without
limiting
the batteries. Also, limited robot energy should take the weight of the
robots into account.


regards
Steffen Prueter
CoolRUNners
_______________________________________________
robocup-small mailing list
robocup-small at cc.gatech.edu
https://mailman.cc.gatech.edu/mailman/listinfo/robocup-small