Patent ID: 6637544
Filing Date: 2003-10-28
Classification: B62D

Abstract:
An electric power assisted steering assembly comprising a steering mechanism which operatively connects a steering wheel to roadwheels of a vehicle, a torque sensor adapted to produce a first output signal indicative of a torque T carried by a portion of said steering mechanism, an angular velocity sensing sensor for producing a second output signal indicative of an angular velocity of said portion of said steering mechanism, an angular position sensor adapted to produce a third output signal dependent on an angular position of said portion of said steering mechanism, an electric motor operatively connected to said steering mechanism, a signal processing unit adapted to receive said first output signal and said second output signal and to produce a torque demand signal representative of an assistance torque to be applied to said steering mechanism by said motor, and a motor drive stage adapted to provide a drive current to said motor responsive to said torque demand signal, and in which said torque demand signal includes a damping component that is dependent upon said first output signal, said second output signal and said third output signal.