Vehicle dynamic control using pulsed active steering strategy

摘要

A pulse active steering control system and method for use in a motor vehicle for improving vehicle stability by reducing a likelihood for rollover and/or skidding sends pulses to the steerable wheels whenever a rollover coefficient and/or the difference between the estimated and actual yaw rate is outside a predetermined range. The pulses are asymmetrical in the form of a smooth curve with a gradually increasing rapid rising edge and a slower falling edge and provide steering input that, along with the driver steering input, returns the rollover coefficient and/or yaw rate to the predetermined range to reduce the likelihood of rollover and/or skidding.

主权项

1. A pulse active steering control system for use in a motor vehicle to improve vehicle stability by reducing a likelihood of rollover and/or skidding, said motor vehicle having at least four wheels, at least two of which are steerable wheels and a driver, said system comprising a rollover estimator that calculates a rollover coefficient of said vehicle, a steering input from said driver feeding feeding into a tire model which calculates tire forces and then feeds the resulting tire forces to a yaw/roll model, said yaw/roll model then calculating a longitudinal and lateral velocity as well as a yaw rate, roll angle and roll rate of said vehicle and feeding the data to said roll over estimator to calculate the rollover coefficient, a controller being programmed to determine whether said rollover coefficient is beyond a predetermined range for said rollover threshold for said vehicle, if said rollover coefficient is within said range for said rollover threshold said controller being programmed not to interfere with operation of said vehicle, if said rollover coefficient is beyond said range of said rollover threshold said controller immediately activating steering pulses, modifying an amplitude of said pulses with respect to a current steering input from said driver and an error signal of said rollover coefficient, said controller sending pulses to provide extra steering to steering provided by said steering input from said driver in order to reduce a likelihood of rollover by varying said rollover coefficient to a value closer to or within said range of said rollover threshold and ultimately to be within said range of said rollover threshold.