Modifying robotic controller

Well my school is entering in the botball competitions this year.

To give us every advantage possible this year i was looking at modifying the controller board seen here to run more efficiently.

The course time is 2 minutes and involves running several dc motors along with sensors and servos. The battery is nickel and I want to upgrade them to lithium ion batteries to increase run time. Along with that I wish to overvolt the dc motors so 100% is their true limit.

The DC motors are controlled with an analog output, so to up the voltage to its max it must also do so retaining the original signal.

What circuit would I have to make to do this for 4 motors?

Normally, motors would be supplied power from a different source. The signal from a controller board would essentially control a "switch" that would control the flow of power to the motors. This would allow you to use, say, a 5V source for your logic and computation, and a 12V source to power your motors. If this is your set up, then all you need to do is increase the motor's supply voltage.

If your motor is powered directly by your controller board (there's only two wires, one may be ground or your high voltage, the other is signal), then you would have to raise the operating voltage of your controller board. This is trickier, because if you raise the voltage too much, you may burn out some of the components on the board.

Google "motor controller" for some helpful information.

BTW, it sounds like the motors aren't running at their max already? You should look at the specs of your motors and make sure that you know the limits.

The motors we use are servers, modified servos that spin freely, and lego kit motors. The lego motors do not run at their full capacity. The lego motors are what i am looking to modify, and if I burn out one or two it dosent matter much.