Abstract
Substructure decoupling consists in the identification of the dynamic behaviour of a structural subsystem, starting from the dynamic behaviour of both the assembled system and the residual subsystem (the known portion of the assembled system). The degrees of freedom (DoFs) of the coupled system can be partitioned into internal DoFs (not belonging to the couplings) and coupling DoFs. In direct decoupling, a fictitious subsystem that is the negative of the residual subsystem is added to the coupled system, and appropriate compatibility and equilibrium conditions are enforced at interface DoFs. Compatibility and equilibrium can be required either at coupling DoFs only (standard interface), or at additional internal DoFs of the residual subsystem (extended interface), or at some coupling DoFs and some internal DoFs of the residual subsystem (mixed interface). In this paper, a test bench is considered made by a cantilever column with two staggered short arms coupled to a horizontal beam. This involves both flexural and torsional DoFs, on which rotational FRFs are quite difficult to measure. Using a mixed interface, rotational DoFs are neglected and substituted by internal translational DoFs. Experimental results are presented and discussed.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
de Klerk D, Rixen DJ, Voormeeren S (2008) General framework for dynamic substructuring: history, review, and classification of techniques. AIAA J 46(5):1169–1181
Sestieri A, Salvini P, D’Ambrogio W (1991) Reducing scatter from derived rotational data to determine the frequency response function of connected structures. Mech Syst Signal Process 5(1):25–44
Stanbridge A, Ewins D (1996) Measurement of translational and angular vibration using a scanning laser Doppler vibrometer. Shock Vib 3:141–152
Bello M, Sestieri A, D’Ambrogio W, La Gala F (2003) Development of PZT’s as rotational transducers. Mech Syst Signal Process 17(5): 1069–1081
D’Ambrogio W, Fregolent A (2008) Promises and pitfalls of decoupling procedures. In: Proceedings of 26th IMAC, Orlando
Sjövall P, Abrahamsson T (2008) Substructure system identification from coupled system test data. Mech Syst Signal Process 22(1):15–33
D’Ambrogio W, Fregolent A (2010) The role of interface DoFs in decoupling of substructures based on the dual domain decomposition. Mech Syst Signal Process 24(7):2035–2048. doi:10.1016/j.ymssp.2010.05.007, also in Proceedings of ISMA 2010, 1863–1880, Leuven (Belgium)
D’Ambrogio W, Fregolent A (2011) Direct decoupling of substructures using primal and dual formulation. In: Conference proceedings of the society of experimental mechanics series, vol 4. Linking models and experiments, vol 2, 31 January–3 February 2011. Springer, Jacksonville, pp 47–76
D’Ambrogio W, Fregolent A (2012) Direct hybrid formulation for substructure decoupling. In: Conference proceedings of the society for experimental mechanics series, vol 27. Topics in experimental dynamics substructuring and wind turbine dynamics, vol 2, 30 January–2 February 2012. Springer, Jacksonville, pp 89–107
D’Ambrogio W, Fregolent A (2014) Inverse dynamic substructuring using direct hybrid assembly in the frequency domain. Mech Syst Signal Process 45(2):360–377
Voormeeren SN, Rixen DJ (2012) A family of substructure decoupling techniques based on a dual assembly approach. Mech Syst Signal Process 27:379–396. doi:10.1016/j.ymssp.2011.07.028
D’Ambrogio W, Fregolent A (2014) Are rotational DoFs essential in substructure decoupling? In: Allen M, Mayes R, Rixen D (eds) Dynamics of coupled structures, vol 1. Conference proceedings of the society for experimental mechanics series. Springer International Publishing, Heidelberg, pp 27–36
Acknowledgements
This research is supported by grants from University of Rome La Sapienza and University of L’Aquila.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2015 The Society for Experimental Mechanics, Inc.
About this paper
Cite this paper
D’Ambrogio, W., Fregolent, A. (2015). Ignoring Rotational DoFs in Decoupling Structures Connected Through Flexotorsional Joints. In: Allen, M., Mayes, R., Rixen, D. (eds) Dynamics of Coupled Structures, Volume 4. Conference Proceedings of the Society for Experimental Mechanics Series. Springer, Cham. https://doi.org/10.1007/978-3-319-15209-7_6
Download citation
DOI: https://doi.org/10.1007/978-3-319-15209-7_6
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-15208-0
Online ISBN: 978-3-319-15209-7
eBook Packages: EngineeringEngineering (R0)