Design and testing of a MRF rotational damper for vehicle applications

Abstract

Adaptive dampers are an interesting solution for conjugating the necessity of controllabledevices and low power consumption. Magneto-rheological fluids (MRF) can beprofitably employed in adaptive dampers because of the significant variation offluid parameters with magnetic field properties. This paper focuses on the designprocess of an innovative rotational MR damper specifically created to be placed inthe front-wheel suspension of a compact car. The advantages of the rotationaldamper and the definition of the optimal design are described. The proposeddamper significantly reduces several key problems associated with MR devices: thequantity of fluid required, the sedimentation of ferromagnetic particles in thesuspension and the abrasion of the seals. In fact, with this solution, low averageworking pressure, low flow velocity through valves, a wide range of variable dampingcharacteristics, and high durability of the damper can be achieved. Thanks to thisinnovative component, different new architectures for adaptive suspension systemscan be developed to have a planar distribution of the suspension componentswith a consequent space optimization and size reduction in the vertical direction.