Abstract
This article describes a new method and device for measuring the rigid-body properties of mechanical structures (the inertia tensor, the center of gravity coordinates, and optionally the mass). The setup consists of a platform constrained from underneath by soft coil springs and supported at its center by a 5-DOF air bearing mechanism. Following a random push by hand, laser distance sensors measure the platform’s free vibrations. The rigid-body properties are then obtained by fitting a numerical model to the free vibration signals. The model’s key components (a mass matrix, a stiffness matrix, and a kinematic transformation matrix) are obtained by calibration. Together with the unknown rigid-body properties, the three matrices define the natural frequencies and unscaled mode shapes, which are fitted to the sensor signals directly in time domain. A prototype of the device is presented and its accuracy is evaluated in an extensive series of tests. Advantages over previous methods include a faster and simpler procedure, higher accuracy, lower frequencies, and an unlimited work space.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Heydinger G, Durisek N, Coovert D, Guenther D, Novak S (1995) The design of a vehicle inertia measurement facility. SAE Trans 104(6): 69–77
Lio MD, Doria A, Lot R (1999) A spatial mechanism for the measurement of the inertia tensor: theory and experimental results. ASME J Dyn Syst Meas Contr 121–1:111–116
Hahn H, Leimbach K, Piepenbrink A (1994) Inertia parameter identification of rigid bodies using a multi-axistest facility. In: Proc. IEEE international conference on control and applications, pp 1735–1737, 1994
Hahn H, Niebergall M (2001) Development of a measurement robot for identifying all inertia parameters of a rigid body in a single experiment. IEEE Trans Contr Syst Tech 9(2):416–423
Goertz H (2007) Identifikation von Fahrzeugträgheitsparametern in Fahrversuchen und auf Prüfständen. Ph.D. thesis, Institut für Kraftfahrwesen, RWTH Aachen
Bretl J, Conti P (1987) Rigid body mass properties from test data. In: Proc. 5th international modal analysis conference (IMAC), pp 655–689
Conti P, Bretl J (1989) Mount stiffness and inertia properties from modal test data. ASME J Vib Acoust Stress Reliab Des 111:134–138
Wei Y, Reis J (1989) Experimental determination of rigid body inertia properties. In: Proc. 7th international modal analysis conference (IMAC), pp 603–606, 1989
Kloepper R, Okuma M (2009) Elimination of bias errors due to suspension effects in frf-based rigid body property identification. ASME J Dyn Syst Meas Contr 131(4):041005
Kloepper R (2009) A measurement system for rigid body properties enabled by gravity-dependent suspension modeling. Ph.D. thesis, Tokyo Institute of Technology
Kloepper R, Akita H, Okuma M, Terada S (2010) An experimental identification method for rigid body properties enabled by gravity-dependent suspension modelling. In: Proc. 1st joint international conference on multibody system dynamics, 2010
Malekjafarian A, Ashory M, Khatibi M (2011) Estimation of rigid body properties from the results of operational modal analysis. Struct Dynam 3:1559–1567
Malekjafarian A, Ashory M, Khatibi M (2013) Identification of inertia properties from the results of output-only modal analysis. Arch Appl Mech 83(6):923–937
Kloepper R, Okuma M, Krueger J (2013) A new process for measuring complete inertia properties. MTZ Worldwide 74(3):40–44
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2014 The Society for Experimental Mechanics, Inc.
About this paper
Cite this paper
Kloepper, R., Okuma, M., Bienert, J. (2014). A Compact Device for Measuring Rigid-Body Properties Based on Five Unscaled Modes. In: De Clerck, J. (eds) Topics in Modal Analysis I, Volume 7. Conference Proceedings of the Society for Experimental Mechanics Series. Springer, Cham. https://doi.org/10.1007/978-3-319-04753-9_22
Download citation
DOI: https://doi.org/10.1007/978-3-319-04753-9_22
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-04752-2
Online ISBN: 978-3-319-04753-9
eBook Packages: EngineeringEngineering (R0)