ELECTRORHEOLOGICAL DAMPERS .2. TESTING AND MODELING

Electrorheological (ER) materials develop yield stresses on the order of 5-10 kPa in the presence of strong electric fields. Viscoelastic an d yielding material properties can be modulated within milli-seconds. An analysis of flowing ER materials in the limiting case of fully deve loped steady flow results in simple approximations for use in design. Small-scall experiments show that these design equations can be applie d to designing devices in which the flow is unsteady. More exact model s of ER device behavior can be determined using curve-fitting techniqu es in multiple dimensions. A previously known curve-fitting technique is extended to deal with variable electric fields. Experiments are des cribed which illustrate the potential for ER devices in large-scale da mping applications and the accuracy of the modeling technique.