The Possibility of Using a System with an Inertial Element as an Impact Damper

Momentum exchange impact dampers (MEIDs) were proposed to control the shock responses of mechanical structures. They were applied to reduce floor shock vibrations and control lunar/planetary exploration spacecraft landings. MEIDs are required to control an object’s velocity and displacement, especially for applications involving spacecraft landing. Previous studies verified numerous MEID performances through various types of simulations and experiments. However, previous studies discussing the optimal design methodology for MEIDs are limited. This study explicitly derived the optimal design parameters of MEIDs, which control the controlled object’s displacement and velocity to zero in one-dimensional motion. In addition, the study derived sub-optimal design parameters to control the controlled object’s velocity within a reasonable approximation to derive a practical design methodology for MEIDs. The derived sub-optimal design methodology could also be applied to MEIDs in two-dimensional motion. Furthermore, simulations conducted in the study verified the performances of MEIDs with optimal/sub-optimal design parameters.

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Multiunit impact damper—Re-examined

Journal of Sound and Vibration ◽

10.1016/s0022-460x(85)80015-8 ◽

1985 ◽

Vol 103 (4) ◽

pp. 457-469 ◽

Cited By ~ 37

Author(s):

C.N. Bapat ◽

S. Sankar

Keyword(s):

Impact Damper

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Dynamics and Performance of a Harmonically Excited Vertical Impact Damper

Journal of Vibration and Acoustics ◽

10.1115/1.2827364 ◽

2008 ◽

Vol 130 (2) ◽

Cited By ~ 8

Author(s):

Sanjiv Ramachandran ◽

George Lesieutre

Keyword(s):

Loss Factor ◽

Vertical Direction ◽

Theoretical Models ◽

Coefficient Of Restitution ◽

Numerical Continuation ◽

Particle Impact ◽

Impact Damper ◽

High Loss ◽

Wide Range ◽

And Performance

Particle impact dampers (PIDs) have been shown to be effective in vibration damping. However, our understanding of such dampers is still limited, based on the theoretical models existing today. Predicting the performance of the PID is an important problem, which needs to be investigated more thoroughly. This research seeks to understand the dynamics of a PID as well as those parameters which govern its behavior. The system investigated is a particle impact damper with a ceiling, under the influence of gravity. The base is harmonically excited in the vertical direction. A two-dimensional discrete map is obtained, wherein the variables at one impact uniquely dictate the variables at the next impact. This map is solved using a numerical continuation procedure. Periodic impact motions and “irregular” motions are observed. The effects of various parameters such as the gap clearance, coefficient of restitution, and the base acceleration are analyzed. The dependence of the effective damping loss factor on these parameters is also studied. The loss factor results indicate peak damping for certain combinations of parameters. These combinations of parameters correspond to a region in parameter space where two-impacts-per-cycle motions are observed over a wide range of nondimensional base accelerations. The value of the nondimensional acceleration at which the onset of two-impacts-per-cycle solutions occurs depends on the nondimensional gap clearance and the coefficient of restitution. The range of nondimensional gap clearances over which two-impacts-per-cycle solutions are observed increases as the coefficient of restitution increases. In the regime of two-impacts-per-cycle solutions, the value of nondimensional base acceleration corresponding to onset of these solutions initially decreases and then increases with increasing nondimensional gap clearance. As the two-impacts-per-cycle solutions are associated with high loss factors that are relatively insensitive to changing conditions, they are of great interest to the designer.

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Modeling the fine particle impact damper

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2010.04.004 ◽

2010 ◽

Vol 52 (7) ◽

pp. 1015-1022 ◽

Cited By ~ 21

Author(s):

Yanchen Du ◽

Shulin Wang

Keyword(s):

Fine Particle ◽

Particle Impact ◽

Impact Damper

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Design and Characterization of a Compact Impact Damper for High Impulsive Loads

44th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference ◽

10.2514/6.2003-1645 ◽

2003 ◽

Cited By ~ 2

Author(s):

William Facey ◽

Nicholas Rosenfeld ◽

Norman Wereley

Keyword(s):

Impact Damper ◽

Impulsive Loads

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Study On Energy Dissipation Mechanism of an Impact Damper System

Journal of Computational and Nonlinear Dynamics ◽

10.1115/1.4053508 ◽

2022 ◽

Author(s):

Vinayaravi R ◽

Jayaraj Kochupillai ◽

Kumaresan D ◽

Asraff A. K

Keyword(s):

Energy Dissipation ◽

Numerical Simulations ◽

Fundamental Frequency ◽

Low Frequency ◽

High Amplitude ◽

Lagrangian Multiplier ◽

Impact Damper ◽

Contact Algorithm ◽

Dissipation Of Energy ◽

Excitation Time

Abstract The objective of this paper is to investigate how higher damping is achieved by energy dissipation as high-frequency vibration due to the addition of impact mass. In an impact damper system, collision between primary and impact masses cause an exchange of momentum resulting in dissipation of energy. A numerical model is developed to study the dynamic behaviour of an impact damper system using a MDOF system with Augmented Lagrangian Multiplier contact algorithm. Mathematical modelling and numerical simulations are carried out using ANSYS FEA package. Studies are carried out for various mass ratios subjecting the system to low-frequency high amplitude excitation. Time responses obtained from numerical simulations at fundamental mode when the system is excited in the vicinity of its fundamental frequency are validated by comparing with experimental results. Magnification factor evaluated from numerical simulation results is comparable with those obtained from experimental data. The transient response obtained from numerical simulations is used to study the behaviour of first three modes of the system excited in vicinity of its fundamental frequency. It is inferred that dissipation of energy is a main reason for achieving higher damping for an impact damper system in addition to being transformed to heat, sound, and/or those required to deform a body.

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