Thursday November 17, 2011 4:00-5:00 p.m.
ME-EM building, Room 112
Professor and Director, Center for Vehicle Systems & Safety, Virginia Tech Dept. of Mechanical Engineering
Magneto rheological (MR) fluids consist of a carrier fluid and micron-sized ferrous particles that when subjected to a magnetic field enables the fluid to have a varying yield stress, dependant on the magnetic flux density. This presentation will provide a historical review of MR fluids for vehicle suspensions. It also provides the current state of MR devices as well as a perspective on the future direction of MR technology for vehicle applications. Some of the successes of the MR devices are discussed along with some of their challenges. It is noted that although our understanding of the MR fluids in valve and shear mode is reasonably advanced, their behavior in squeeze mode remains relatively unknown. The results of a preliminary study show that in squeeze mode MR fluids can provide a large range of forces that can be controlled with a relatively low amount of electrical power, making them suitable for compact force actuators that can be used in aerospace, automotive, robotics, and biomedical devices.