000 04124ntm a2200373 i 4500
999 _c99388
_d99394
003 MY-KuUP
005 20251125110730.0
006 t||||fr|||| 000 0
007 ta
008 230414t20232023my a|||fr|||| 000 0 eng d
020 _aTHE0009459 (Local)
_qHardback
040 _aUMP
_beng
_cUMP
_erda
090 _aFTKMA .R35 2023 r Thesis
100 1 _aMuhammmad Rais Rahim,
_eauthor.
245 1 0 _aDevelopment of a non-inertia mass fibre bragg grating accelerometer based on a single diaphragm mechanism and its vibration response analysis /
_cMuhammmad Rais Rahim
264 1 _aPahang :
_bUMP,
_c2023
264 4 _c© 2023
300 _axvii, 117 pages:
_bIllustration ;
_c30 cm.+
_e1 CD ROM
336 _2rdacontent
_atext
336 _2rdacontent
_atext
337 _2rdamedia
_aunmediated
337 _2rdamedia
_acomputer
338 _2rdacarrier
_avolume
338 _2rdacarrier
_acomputer disc
347 _2rda
_atext file
_bPDF
500 _aFaculty of Mechanical & Automotive Engineering Technology
502 _aThesis (Master of Science) -- Universiti Malaysia Pahang – 2022
504 _aIncludes bibliographical reference
520 3 _aThe development of the fibre Bragg grating (FBG) sensor as an accelerometer has received considerable attention since the FBG sensor is remarkably sensitive to strain. The inclusion of inertia mass in the diaphragm-type FBG accelerometer increased the complexity of the accelerometer mechanism. Moreover, numerical and experimental studies are not comprehensively reported and published, despite the fact that several accelerometer aspects should be thoroughly investigated. The overall aim of this thesis is to present a new design of a small and fabricable, diaphragm-type non-inertia mass FBG accelerometer (FBGA-SD) that comes with new features, as well as its comprehensive numerical and experimental investigation. This research begins with the development of five FBGA-SD designs and their concept scoring. The dynamic of the final FBGA-SD design is then investigated using finite element modal analysis followed by harmonic response analysis to determine the location of maximum strain on the diaphragm to place the FBG sensor. The functionality of the FBGA-SD is finally investigated through transient response analysis and experimental work as well as sensitivity determination. The final design of FBGA-SD with dimensions of 16 mm × 16 mm × 10 mm and a weight of 4 grammes has eliminated the weaknesses of the previous four FBGA-SD designs, with new features introduced particularly in the lengthening of the FBG tunnel and the invention of a through-hole for monitoring the FBG sensor inside the diaphragm pocket. Finite element modal analysis has ensured that the first natural frequency of the diaphragm is low (13, 380 Hz) and far from that of the housing (20, 689 Hz) in order to avoid the dynamic of the housing affecting accelerometer response. The location of the maximum strain for placing the FBG sensor on the diaphragm is determined, with the two best positions found to be in the middle and along the edges of the diaphragm. Due to the fact that the edge of the diaphragm is a clamped area, positioning the FBG sensor in its middle would be ideal. The response of the wavelength shift obtained from transient response analysis and experiment agrees well in terms of pattern and phase but differs by 50% of amplitude. It should also be mentioned that the base acceleration and the wavelength shift both demonstrate that they are in the same phase with one another. The 50% difference in amplitude of the wavelength shift reflects the sensitivity of the FBGA-SD, where the experimental sensitivity is 9.64×10-5 nm/g and the transient response analysis gives 4.79×10-5 nm/g, valid for the range of excitation frequencies of 10 to 147 Hz and maximum base acceleration of 10.5 m/s2. Within these ranges, the sensitivity is not frequency dependent.
610 2 0 _aFaculty of Mechanical & Automotive Engineering Technology
_xDissertations
650 0 _aUniversities and colleges
_xDissertations
650 0 _aThesis
942 _2lcc
_cTHESIS