Theory and Principles of Magnetorheological Fluids as Smart Materials and Their Application on the design of a Mechatronic Leg Prosthesis-Edición Única

Magnetorheological (MR) fluids are mainly suspensions of ferromagnetic particles of micrometric size in a carrier liquid. They can be considered smart materials because of their ability to achieve a wide range of viscosities in a fraction of milliseconds under application of a magnetic field. The purpose of the present work is to propose a theoretical basis which supports the rheological behavior of a MR fluid making an analogy with phase transformation, which corresponds to a natural phenomena, it is introduced in a non-explored field because, scientist have not related this natural behavior with a synthetic material such as MR fluid. Some experiment are carried out in order to verify the theory and based on that behavior, MR fluid will be applied in the design of mechatronic leg prosthesis. This work is divided in mainly three specific stages: Chemical formulation and characterization of MR fluid, modeling of the flow phenomena in MR fluids and mechanical design of a mechatronic leg prosthesis using MR fluid. The results of the thesis were a proposed model based on phase transformation, the validation of such model using experimental method and the application in mechatronic leg prosthesis.