Oh, my aching back! - Protective aircraft seat design using magnetorheological systems

At Cnam, Paris, October 7th 2015, 2 p.m.

Norman M. Wereley
Minta Martin Professor and Chair, Department of Aerospace Engineering, University of Maryland, College Park, USA

The ability to dissipate energy in vehicle systems, especially with the goal of protecting occupants from potentially injurious vibration, repetitive shock, crash and blast loads, is becoming a critical issue as the cumulative impact of these load spectra on chronic health and acute injury are becoming better understood. Energy is dissipated utilizing a stroking element, such as a hydraulic damper or energy absorber.

However, it is difficult to anticipate precisely what range occupant mass an isolation system might be expected to protect, or what vibration and shock spectra the system might encounter. Therefore, adaptation of stroking load is required to enable a system to have sufficient adjustability or control capability to effectively dissipate energy across a wide range of anticipated and even unanticipated disturbances. The goals of this research are threefold: (1) to develop field dependent or controllable energy absorbing materials, especially magnetorheological (MR) fluids, (2) to develop magneto-rheological energy absorbers (MREAs) to enable adaptation of stroking load in order to minimize lumbar loads in the human spine and thereby minimizing the potential for injury, and (3) to protect occupants or payloads from a wide range of vibration and shock spectra, as well as to accommodate a population of occupants of different mass.

Applications to crew seating and landing gear in rotorcraft will be discussed. The transition of these protective seat technologies to ground vehicles and high speed boats will also be discussed.


Dr. Wereley‘s research interests are in dynamics and control of smart structures applied to helicopters and other aerospace and automotive systems, with emphasis on active and passive vibration isolation, shock mitigation (especially occupant protection systems), and actuation systems. Dr. Wereley has published over 200 journal articles, 16 book chapters, and over 275 conference articles. Dr. Wereley is an inventor on 19 patents and several patents pending. Dr. Wereley is editor of the Journal of Intelligent Material Systems and Structures and associate editor of Smart Materials and Structures and AIAA Journal. He is the recipient of several awards including AIAA National Capital Section Engineer of the Year (2009), AIAA Sustained Service Award (2011), the AHS Harry T. Jensen Award (2011), and the ASME Adaptive Structures and Materials Systems Best Paper Award in Structural Dynamics and Control (2004, 2012). Dr. Wereley is also the recipient of the ASME Adaptive Structures and Material Systems Prize (2012) and the SPIE Smart Structures and Materials Lifetime Achievement Award (2013). Dr. Wereley is a fellow of AIAA, ASME, SPIE, and the Institute of Physics. He is also a senior member of IEEE and a lifetime member of AHS. Dr. Wereley has a B.Eng. (1982) from McGill University and M.S. (1987) and Ph.D. (1990) from the Massachusetts Institute of Technology.

Laboratoire de Mécanique des Structures et des Systèmes Couplés - LMSSC