Semiactive control devices have received significant attention in recent years because they offer the adaptability of active control devices without requiring the associated large power sources. Magnetorheological (MR) dampers are semiactive control devices that use MR fluids to produce controllable dampers. They potentially offer highly reliable operation and can be viewed as fail-safe in that they become passive dampers should the control hardware malfunction. To develop control algorithms that take full advantage of the unique features of the MR damper, models must be developed that can adequately characterize the damper's intrinsic nonlinear behavior. Following a review of several idealized mechanical models for controllable fluid dampers, a new model is proposed that can effectively portray the behavior of a typical MR damper. Comparison with experimental results for a prototype damper indicates that the model is accurate over a wide range of operating conditions and is adequate for control design an...

Phenomenological model for magnetorheological dampers

This tutorial/survey paper: (1) provides a concise point of departure for researchers and practitioners alike wishing to assess the current state of the art in the control and monitoring of civil engineering structures; and (2) provides a link between structural control and other fields of control theory, pointing out both differences and similarities, and points out where future research and application efforts are likely to prove fruitful. The paper consists of the following sections: section 1 is an introduction; section 2 deals with passive energy dissipation; section 3 deals with active control; section 4 deals with hybrid and semiactive control systems; section 5 discusses sensors for structural control; section 6 deals with smart material systems; section 7 deals with health monitoring and damage detection; and section 8 deals with research needs. An extensive list of references is provided in the references section.

Structural control: past, present, and future

Supplemental energy dissipation: state-of-the-art and state-of-the- practice

http://sstl.cee.illinois.edu/papers/Engineering_Structures.pdf

Large-scale MR fluid dampers: modeling and dynamic performance considerations

Semi-active control devices have received significant attention in recent years because they offer the adaptability of active control devices without requiring the associated large power sources. Magnetorheological (MR) dampers are semi-active control devices that use MR fluids to produce controllable dampers. They potentially offer highly reliable operation and can be viewed as fail-safe in that they become passive dampers should the control hardware malfunction. To develop control algorithms that take maximum advantage of the unique features of the MR damper, models must be developed that can adequately characterize the damper’s intrinsic nonlinear behavior. Following a review of several idealized mechanical models for controllable fluid dampers, a new model is proposed that can effectively portray the behavior of a typical magnetorheological damper. Comparison with experimental results for a prototype damper indicates that the model is accurate over a wide range of operating conditions and is adequate for control design and analysis.

/pdf/phenomenological-model-of-a-magnetorheological-damper-51ad97gf78.pdf

Phenomenological Model of a Magnetorheological Damper

A new type of magnetic fluid and several classes of new devices utilizing this fluid have been developed at the National Bureau of Standards. One application of this fluid has been in electromagnetic clutches, but the electro-magnetically controlled mixture offers promise for other uses also.

The Magnetic Fluid Clutch

The notched-disk memory appears to be a very significant development in electromechanical information storage techniques. Its possible applications are manifold, including such diversified automatic information processing activities as electronic computing, telephone switching, ticket reservations, optical recording, and business accounting.

The notched-disk memory

The nature and quality of the information and needs of the researcher are important factors in the efficient use of retrieval tools. Their potentialities and limitations in the art of information searching are reviewed.

http://ieeexplore.ieee.org/iel5/6413714/6445119/06445131.pdf

Jacob Rabinow

Papers

The Magnetic Fluid Clutch

The notched-disk memory

Presently available tools for information retrieval