Optimal tractive force control method for ground vehicles

1. Field of the Invention A method is provided for controlling tractive force of a ground vehicle. The method is adaptive to vehicles which have both driven axles and non driven axles or, alternatively, vehicles which have only driven axles. Slip is determined either by comparing the angular velocities of the driven and non driven axles or, alternatively, by monitoring the angular velocity of the driven axle as a function of time to determine an instantaneous angular acceleration. The tractive force command is varied as a function of slip of the driven axle and is increased or decreased relative to the tractive force request provided by the operator in order to most efficiently respond to the operator command.