[GUI]

They accelerated at the same rate because acceleration is a function of mass and force. If both bots were maximum weight, the mass and the force of friction provided by the wheels would be the same. Since the motors provided more force than the friction of the wheels, either robot could only apply, at most, the frictional force of the wheels. This is different than in previous years where the frictional force of the wheels was greater than the output possible with the motors, a situation where the motor output was the limiting factor (and more motors = more force, assuming identical motors). The difference is that this year the limiting factor is friction, while previously it has been motor power.