IMPROVEMENT OF THE ASSESSMENT OF THE ABSOLUTE ANGULAR POSITION OF A STEERING WHEEL BY CONSIDERING ITS SITUATION WHEN SWITCHING OFF THE VEHICLE

摘要

The present invention relates to a method for estimating the absolute angular position (P_absolute_SW) of a steering wheel (2) equipping a power-steering device (1), during which the position, referred to as "relative steering wheel position" (P_relative_SW), of the shaft (13) of a power-steering motor (11) is assessed, a first estimation (Angle1) of the absolute angular position of the steering wheel (2) is assessed from at least one first model using the speed difference between the left (14) and right (15) rear wheels, a first dynamic offset (OffsetDYN_RS) equal to the difference between the first estimation (Angle1) of the absolute angular position of the steering wheel (2) and the relative steering wheel position (P_relative_SW) is estimated, and the absolute angular position of the steering wheel is calculated by adding to the relative steering wheel position (P_relative_SW) a total compensation offset (Offset_final) which is determined from the first dynamic offset (OffsetDYN_RS), and which also considers, when restarting the vehicle (6), a switching-off offset (Offset_save) which corresponds to the value of the total compensation offset (Offset_final) at the time when the vehicle was previously switched off.