Inlämning av Examensarbete / Submission of Thesis

HARSHITH KUMAR NOOJI VENKATRAMANA; GOWTHAM NATARAJAN; VIJAY VARMA BHUPATHIRAJU BTH-AMT-EX--2011/D-02--SE, pp. 66. ING/School of Engineering, 2011.

The work

Författare / Author: HARSHITH KUMAR NOOJI VENKATRAMANA, GOWTHAM NATARAJAN, VIJAY VARMA BHUPATHIRAJU
hkno09@student.bth.se, gowtham.natarajan@gmail.com, vijayvarma.bh@gmail.com
Titel / Title: Development and Validation of Methods for Nonlinear System Identification
Abstrakt Abstract:

In structural engineering, it is common to neglect the nonlinear effects. This is no longer feasible with increasing complex designs and higher demands on the simulation models. This thesis presents a study of the concept of nonlinearity in a structure with emphasis on system identification. Two identification methods are presented in this work. The first method uses a least-square technique in time domain and the second method uses a least-square technique in the frequency domain. These two methods are compared with each other for two different types of excitation: transient and random excitation. The study involves three stages; theoretical modeling, simulation and experimental verification. A single degree of freedom system is used for the simulations and a beam with a local nonlinearity is used in the experiment. The result shows that both identification methods work on simulated data, whereas only the frequency domain method worked well on experimental data. The transient excitation was better on simulated data compared to random excitation, however in the experiment the random excitation gives a more stable and reasonable result.

Ämnesord / Subject: Maskinteknik - Mechanical Engineering\Structural Mechanics

Nyckelord / Keywords: Nonlinear vibrations, System Identification, Simulation, Shaker testing, Impulse testing.

Publication info

Dokument id / Document id: houn-8l9h9a
Program:/ Programme Masters Programme in Mechanical Engineering 120 ECTS
Registreringsdatum / Date of registration: 08/31/2011
Uppsatstyp / Type of thesis: Masterarbete/Master's Thesis (120 credits)

Context

Handledare / Supervisor: Andreas Josefsson
andreas.josefsson@bth.se
Examinator / Examiner: Ansel Berghuvud
Organisation / Organisation: Blekinge Institute of Technology
Institution / School: ING/School of Engineering

+46 455 38 50 00
Anmärkningar / Comments:

Polhemsgatan 28B, LGH 18
Karlskrona 371 40,

Mobile:
Harshith Nooji -0734898038
Gowtham Natarajan -0734898039
Vijay Varma BH -0734898259

Files & Access

Bifogad uppsats fil(er) / Files attached: bth2011natarajan.pdf (956 kB, öppnas i nytt fönster)