Design, Simulation, and Fabrication of a Lightweight Magneto Rheological Damper

Mountain biking has significantly evolved recently, thanks to utilizing cutting-edge technologies in mountain bicycle design and fabrication. In this research we study development of a semi-active suspension system using magneto-rheological (MR) fluid dampers instead of conventional oil based shocks. MR dampers are devices with magnetic field dependent damping characteristics.Low power consumption, high controllability, quick response, and high durability are among the major features of MR dampers. In this work we first investigate the damping characteristics of MR dampers to find out if characteristics comparable to the conventional shocks used in mountain bikes can be achieved. To this end,experimental tests were performed on an off-the-shelf MR damper. The results indicate that damping characteristics similar to the ones used in mountain bikes can in fact be achieved using MR technology.However, requirements such as small weight and wide dynamic range have to be addressed in designing a MR damper for mountain bikes. These considerations are studied in this thesis by formulating a simple design followed by a constrained optimization problem and designing the damper accordingly. Utilizing Finite element modeling and simulation tools are further utilized to fine tune and optimize the design.A prototype MR damper is fabricated after the above design steps are carried out.