Magnetorheological energy absorber with dual concentric annular valves

For semi-active shock and vibration mitigation systems using magnetorheological energy absorbers, fail-safe performance is of particular significance if electric power is lost. At the same time, the minimization of the field-off damping force of the magnetorheological energy absorbers at high speed is also important because the damping force due to the viscous damping force at high speed becomes too excessive, and thus, the controllable dynamic range is rapidly reduced. In this article, a fail-safe magnetorheological energy absorber with dual concentric annular valves and an inner-set permanent magnet is proposed to decrease the field-off damping force while keeping an appropriate dynamic range for improving shock and vibration mitigation performance. In the magnetorheological energy absorber, the dual concentric annular valves are configured so as to decrease the baseline damping force, and magnetic activation methods using the electromagnetic coil winding and the permanent magnet are used to maintain appropriate magnetic intensity in these concentric annular valves. An initial field-on damping force is produced by the magnetic field bias generated from the inner-set permanent magnet in consideration of the failure of the electric power supply. The initial field-on damping force of the magnetorheological energy absorbers can be increased (or decreased) by applying positive (or negative) current to the electromagnetic coil winding, and thus, bidirectional controllable damping performance could be realized. After establishing the analytical damping force model of the magnetorheological energy absorber using a Bingham-plastic nonlinear fluid model, its working principle and magnetic properties are analytically validated and analyzed via electromagnetic finite element analysis. The performance of the magnetorheological energy absorber is also theoretically compared with that of a conventional magnetorheological energy absorber with a single valve with the constraint of an identical volume under different excitation velocities.

[1]  Stanley P. Desjardins.  The Evolution of Energy Absorption Systems for Crashworthy Helicopter Seats , 2003 .

[2]  H. Böse,et al.  Performance of magnetorheological fluids in a novel damper with excellent fail-safe behavior , 2009 .

[3]  Norman M. Wereley,et al.  Semi-Active Control of Vertical Stroking Helicopter Crew Seat for Enhanced Crashworthiness , 2007 .

[4]  Subhash Rakheja,et al.  EVALUATION OF VIBRATION AND SHOCK ATTENUATION PERFORMANCE OF A SUSPENSION SEAT WITH A SEMI-ACTIVE MAGNETORHEOLOGICAL FLUID DAMPER , 2002 .

[5]  Xian-Xu Bai,et al.  Analysis and testing of an inner bypass magnetorheological damper for shock and vibration mitigation , 2013, Smart Structures.

[6]  Norman M. Wereley,et al.  A Magnetorheological Damper with Bifold Valves for Shock and Vibration Mitigation , 2007 .

[7]  Norman M. Wereley,et al.  Semi-Active Magnetorheological Helicopter Crew Seat Suspension for Vibration Isolation , 2008 .

[8]  Norman M. Wereley,et al.  Design and testing of a magnetorheological damper to control both vibration and shock loads for a vehicle crew seat , 2010, Smart Structures and Materials + Nondestructive Evaluation and Health Monitoring.

[9]  S. Narayanan,et al.  Response of a quarter car model with optimal magnetorheological damper parameters , 2013 .

[10]  N. Wereley,et al.  Nondimensional analysis of semi-active electrorheological and magnetorheological dampers using approximate parallel plate models , 1998 .

[11]  Yang Ding,et al.  A new magnetorheological damper for seismic control , 2013 .

[12]  Xian-Xu Bai,et al.  A fail-safe magnetorheological energy absorber for shock and vibration isolation , 2014 .

[13]  Janusz Gołdasz.  Study of a magnetorheological fluid damper with multiple annular flow gaps , 2013 .

[14]  Faramarz Gordaninejad,et al.  A novel two-way-controllable magneto-rheological fluid damper , 2010 .

[15]  Changrong Liao,et al.  TECHNICAL NOTE: A study of an inner bypass magneto-rheological damper with magnetic bias , 2007 .

[16]  Wei Hu,et al.  Nonlinear modeling of magnetorheological energy absorbers under impact conditions , 2013 .

[17]  Norman M. Wereley,et al.  Magnetorheological Damper Utilizing an Inner Bypass for Ground Vehicle Suspensions , 2013, IEEE Transactions on Magnetics.

[18]  Xian-Xu Bai,et al.  Pareto Optimization-Based Tradeoff Between the Damping Force and the Sensed Relative Displacement of a Self-sensing Magnetorheological Damper , 2011 .

[19]  Norman M. Wereley,et al.  ADAPTIVE ENERGY ABSORBERS FOR DROP-INDUCED SHOCK MITIGATION , 2011 .