Razvoj avtomatskega modalnega kladiva

Barši Palmić, Tibor (author), Čepon, Gregor (mentor), Boltežar, Miha (comentor)

Že od prvih začetkov eksperimentalne modalne analize inženirska stroka raziskuje najbolj primerne načine vzbujanja najrazličnejših struktur in jih skuša implementirati v čimbolj zanesljivi in učinkoviti obliki. Plod ideje o idealnem impulzu sile je postalo modalno kladivo. Orodje v nekaterih primerih omogoča učinkovito vzbujevalno sredstvo, v drugih pa je vir merilnih negotovosti, katerih posledica je izračun nezanesljivih modalnih lastnosti analizirane strukture. Izboljšava orodja je tako zahtevala izključitev direktnega vpliva človeškega faktorja na meritev in realizacijo generiranja sile s pretvornikom iz električnega signala v mehansko silo. Prototip avtomatskega modalnega kladiva, realiziranega s solenoidom, krmiljenim preko elektronskega vezja, je omogočil generiranje ponovljivega in nastavljivega ter časovno ožjega impulza sile. Z razvitim kladivom smo lahko, za namen določitve modalnih lastnosti strukture, le-to vzbudili v širšem frekvenčnem območju.

• Language: Slovenian
• Keywords: eksperimentalna modalna analiza, impulzno vzbujanje, frekvenčna prenosna funkcija, koherenca, solenoid, induktivnost, generiranje impulzov, RC vezje, 555IC
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [T. Barši Palmić]
• Year: 2019
• Number of pages: XXVII, 68 str.
• PID: 20.500.12556/RUL-109424
• UDC: 531/533:621.318.2:004.3(043.2)
• COBISS.SI-ID: 16834075
• Publication date in RUL: 01.09.2019

BARŠI PALMIĆ, Tibor, 2019, Razvoj avtomatskega modalnega kladiva [online]. Master’s thesis. Ljubljana : T. Barši Palmić. [Accessed 13 June 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=109424

Secondary language

• Language: English
• Title: Development of an automatic modal hammer

Abstract

From the early beginnings of the experimental modal analysis, one of the research focus is oriented towards the development of reliable and efficient ways of dynamic excitation. Usually the excitation is performed using an impact hammer, which proves to be efficient, however the accuracy and the impact location are highly subjected to the user experience. To improve on the realization of ideal impulse force, the human effect had to be excluded and isolated from the force generation with incorporation of an electrical power source to mechanical force transducer. A prototype of an automatic modal hammer with linear solenoid as force generator and 555IC timer as control chip was developed within this thesis. The excitation system is able to generate a reproducible, adjustable and short excitation impulse force, which enables the excitation of the structure in a broader frequency range. In this way it is possible to obtain more precise and reproducible measurement of modal characteristics, compared to a manual impact hammer.

• Keywords: experimental modal analysis, impulse excitation, frequency response function, coherence, solenoid, induction, pulse generation, RC circuit, 555IC