Patent ID: 6580988
Filing Date: 2003-06-17
Classification: B62D

Abstract:
In the method of controlling the rear wheel angle in a vehicle having operator controlled front wheel steering using a front steering handwheel linked to the front wheels; and electronic controller managed, electrical actuator initiated rear wheel steering, said rear wheel steering being managed using a computer based controller in which continually repeated calculation cycles are performed; said method comprising determining the current front wheel angle, determining the current velocity of said vehicle and determining a rear wheel angle by multiplying said current front wheel angle with a value of a ratio of rear wheel angle to front wheel angle, termed R/F gain value, selected for said current vehicle velocity from a database of R/F gain values correlated with steady-state front wheel angles and corresponding steady state vehicle velocities for non side-slip vehicle maneuverability, the improvement in determining said rear wheel angle comprising,applying to said R/F gain value at least one predetermined gain factor based on at least one of (i) the magnitude of a current operator handwheel angle, (ii) the magnitude of said current front wheel angle and (iii) the current time rate of change of said operator handwheel angle.