Patent ID: 7311315

Claim:
An apparatus for controlling stiffness of an anti-roll bar for a vehicle, comprising: an anti-roll bar having piezoelectric ceramics formed therewith, the anti-roll bar interconnecting lower arms of a vehicle suspension system; a power converter connected to a power supply to change an amount of electric power and to supply the electric power to the piezoelectric ceramics of the anti-roll bar; and a controller connected to the power converter to calculate an amount of the electric power needed to provide the piezoelectric ceramics with optimal stiffness based on previously stored vehicle speed and steering angle in response to data detected by a vehicle speed sensor and a steering angle sensor and to control the power converter such that the calculated electric power can be supplied to the piezoelectric ceramics, wherein the anti-roll bar is configured such that an outer circumferential surface thereof is enclosed by the piezoelectric ceramics.