Patent ID: 7107136
Filing Date: 2006-09-12
Classification: B60G,B60T,B60W,B62D

Abstract:
1. Method for determining likelihood of rollover of a vehicle comprising the steps: measuring vehicle lateral acceleration; measuring one of vehicle roll rate and vehicle suspension displacements; from the measured lateral acceleration and the measured one of the vehicle roll rate and the vehicle suspension displacements, deriving a first estimate of roll angle and a first estimate of roll rate; storing a dynamic, closed loop observer equation comprising a model of the vehicle in a first roll mode for roll angles small compared to a reference value indicating two wheel lift-off and a second roll mode for roll angles at least near the reference value indicating two wheel lift-off, the observer equation having a plurality of terms with coefficients; deriving a roll angle index from at least the measured lateral acceleration and the measured one of vehicle roll rate and vehicle suspension displacements; storing values of the coefficients of selected ones of the plurality of terms of the observer equation as functions of the roll angle index, the stored coefficients for each of the selected ones of the plurality of terms having at least a first value corresponding to the first roll mode and a second value corresponding to the second roll mode; deriving a second estimate of roll angle from the observer equation using one of the first values of the stored coefficients and the second values of the stored coefficients based on the derived roll angle index; and determining the likelihood of vehicle roll-over at least in response to the second estimate of roll angle.