FORCE APPROPRIATION METHOD FOR TWO DEGREES OF FREEDOM NONLINEAR SYSTEM

Authors

  • Mohd Shahrir Mohd Sani Advanced Structural Integrity of Vibration Research (ASIVR), Faculty of Mechanical Engineering, University Malaysia Pahang, 26600 Pekan, Pahang, Malaysia
  • Muhamad Norhisham Abdul Rani Dynamics and Control Laboratory, Faculty of Mechanical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia
  • Mohd Azmi Yunus Dynamics and Control Laboratory, Faculty of Mechanical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia
  • Ahmad Azlan Mat Isa Dynamics and Control Laboratory, Faculty of Mechanical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia
  • Liyana Roslan Dynamics and Control Laboratory, Faculty of Mechanical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia

DOI:

https://doi.org/10.11113/jt.v76.5614

Keywords:

Force appropriation, nonlinear, vibration, multivariate mode indicator function

Abstract

In this paper, the vibrations of structures are investigated via force appropriation method in which modes are excited individually by forces. Multivariate mode indicator function (MMIF) is used in the modal testing for investigating the prospective nonlinearities in the structures. The method is applied to simulate two degree of freedom with simple nonlinearities. The results are presented and evaluated to indicate that the method has advantages when it comes to involving in mode by mode identification. Results calculated from modal assurance criteria (MAC) and modal purity indicator (MPI) show that the qualities of evaluating a pure normal mode are in satisfactory. This suggests that force appropriation method for nonlinear structures is reliable and efficient, particularly in terms of the isolation of individual modes and determination of high quality modal parameters.

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Published

2015-09-27

Issue

Vol. 76 No. 8: Robotic, Mechatronics & Computer Engineering

Section

Science and Engineering

License

Copyright of articles that appear in Jurnal Teknologi belongs exclusively to Penerbit Universiti Teknologi Malaysia (Penerbit UTM Press). This copyright covers the rights to reproduce the article, including reprints, electronic reproductions, or any other reproductions of similar nature.

How to Cite

FORCE APPROPRIATION METHOD FOR TWO DEGREES OF FREEDOM NONLINEAR SYSTEM. (2015). Jurnal Teknologi, 76(8). https://doi.org/10.11113/jt.v76.5614