Patent ID: 9616921
Date: 2017-04-11
CPC Classifications: B62D

Claim:
1. A method of adjusting friction of a motor driven power steering (MDPS) unit comprising: detecting road surface conditions of a road on which a vehicle travels; classifying the road on which the vehicle travels into a normal road, a low frictional road, a road having a first uneven road surface, and a road having a second uneven road surface; and varying a supporting force of an active roll stabilizer (ARS) provided in the MDPS unit depending on the detected road surface conditions, wherein the varying the supporting force of the active roll stabilizer comprises: reducing a friction of the MDPS unit of the vehicle when the road on which the vehicle travels is determined as the road having the first uneven road surface, and increasing the friction of the MDPS unit of the vehicle when the road on which the vehicle travels is determined as the low frictional road or the road having the uneven road surface when classifying the road on which the vehicle travels into a normal road, the low frictional road, the road having the first uneven road surface, and the road having the second uneven road surface, the increasing the friction of the MDPS unit of the vehicle further comprising: adjusting the supporting force of the active roll stabilizer to a first preset supporting force when the road on which the vehicle travels is classified into the low frictional road without a vehicle stability management (VSM) operating signal; and adjusting the supporting force of the active roll stabilizer to a second preset supporting force when the road on which the vehicle travels is classified into the low frictional road without the VSM operating signal.