Experimental structural damping analysis in high-speed elastic mechanisms

Mansour Karkoub, Arthur G. Erdman

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

The damping effect is a major obstacle that has to be surmounted in order to obtain precise understanding of elastic mechanisms' behavior. Most researchers tend to neglect the damping effect (due to high cost of experimental equipment or system complexity) or use one of the few available damping theories (Rayleigh, Wilson, etc.). Also, a single damping coefficient is often used over the entire cycle. This assumption might be true if the geometry of the system is conserved during the cycle. However, it has been proven experimentally that in the case of a four-bar mechanism (geometry of the mechanism changes during the cycle), some dynamic properties like the natural frequencies and the damping ratios vary with the geometry. Since damping is an inherently imprecise phenomenon, it can not be represented by a simple mathematical model. Consequently, some experimental analysis of the damping effect in each specific system is necessary for a complete and accurate model. In the case of flexible mechanisms, very few researchers have experimentally approached the structural damping problem. Viscous damping coefficients in the direction of selected degrees of freedom of an elastic-four-bar mechanism are introduced here using a signal processing scheme. These varying coefficients are used to formulate the damping matrices for a high-speed finite element analysis that solves for the mid-point coupler curve of an elastic four-bar mechanism.

Original languageEnglish
Title of host publicationFlexible Mechanism, Dynamics, and Robot Trajectories
EditorsM. McCarthy, S. Derby, A. Pisano
PublisherPubl by ASME
Pages251-258
Number of pages8
Volume24
Publication statusPublished - 1990
Externally publishedYes
Event21st Biennial Mechanism Conference - Chicago, IL, USA
Duration: 16 Sep 199019 Sep 1990

Other

Other21st Biennial Mechanism Conference
CityChicago, IL, USA
Period16/9/9019/9/90

Fingerprint

Damping
Geometry
Degrees of freedom (mechanics)
Natural frequencies
Signal processing
Mathematical models
Finite element method
Costs

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Karkoub, M., & Erdman, A. G. (1990). Experimental structural damping analysis in high-speed elastic mechanisms. In M. McCarthy, S. Derby, & A. Pisano (Eds.), Flexible Mechanism, Dynamics, and Robot Trajectories (Vol. 24, pp. 251-258). Publ by ASME.

Experimental structural damping analysis in high-speed elastic mechanisms. / Karkoub, Mansour; Erdman, Arthur G.

Flexible Mechanism, Dynamics, and Robot Trajectories. ed. / M. McCarthy; S. Derby; A. Pisano. Vol. 24 Publ by ASME, 1990. p. 251-258.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Karkoub, M & Erdman, AG 1990, Experimental structural damping analysis in high-speed elastic mechanisms. in M McCarthy, S Derby & A Pisano (eds), Flexible Mechanism, Dynamics, and Robot Trajectories. vol. 24, Publ by ASME, pp. 251-258, 21st Biennial Mechanism Conference, Chicago, IL, USA, 16/9/90.
Karkoub M, Erdman AG. Experimental structural damping analysis in high-speed elastic mechanisms. In McCarthy M, Derby S, Pisano A, editors, Flexible Mechanism, Dynamics, and Robot Trajectories. Vol. 24. Publ by ASME. 1990. p. 251-258
Karkoub, Mansour ; Erdman, Arthur G. / Experimental structural damping analysis in high-speed elastic mechanisms. Flexible Mechanism, Dynamics, and Robot Trajectories. editor / M. McCarthy ; S. Derby ; A. Pisano. Vol. 24 Publ by ASME, 1990. pp. 251-258
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