Double Adjustable Shock Absorbers Using Electrorheological Fluid

Abstract

Double adjustable shock absorbers allow for adjustment of their yield force and post-yield damping. To emulate the performance of a conventional double adjustable shock absorber, an electrorheological (ER) automotive shock absorber was designed and fabricated at the University of Maryland. An applied electric field between two tubular electrodes, located in the piston head, increases the force required for a given piston rod velocity. Two different shaped gaps between the electrodes, meet the controllable performance requirements of a double adjustable shock. A uniform gap primarily adjust the yield force of the shock absorber, as opposed to a non-uniform gap which allow for control of the post-yield damping. Force measurements from sinusoidal displacement cycles, recorded on a 5 HP mechanical dynamometer, validate the performance of uniform and non-uniform gaps for yield force and post-yield damping adjustments.