Electro-rheological (ER) devices-properties, performance and applications

An electro-rheological (ER) fluid per se is a semi conducting mixture of polarisable polymer particles of high dielectric constant and an insulating liquid of low dielectric constant. When an electric field is applied transverse to the direction of motion of the fluid, the resistance to flow is increased-in a passive fashion by inducing inter particle hydraulic action. The types of ER passive controllers explored so far are given. The squeeze film and Rayleigh types allow for but small displacements and are specifically associated with bearings