Dvoosna horizontalna vlačna kidalica

master's thesis

• Title (english): Horizontal biaxial tensile testing machine
• Author: Antun Jakob Marić
• Mentor: Igor Karšaj (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2020-05-15, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; General Mechanical Engineering (Construction)

Abstract

U ovom radu razvijen je i konstruiran model dvoosne kidalice za za statičko i niskofrekventno dinamičko vlačno ispitivanje bioloških tkiva i mekih polimernih materijala.
U teorijskom dijelu rada opisano je statičko vlačno ispitivanje kao i načini mjerenja deformacija vizualnim metodama. Nabrojane su i opisane neke od već postojećih kidalica koje se koriste u ovu svrhu, s posebnim osvrtom na različite načine prihvata ovisno o ispitivanom materijalu.
Proučeni su dostupni elektromehanički aktuatori na tržištu koji bi bili potrebni za ovu svrhu, te se zbog njihove male nosivosti poprečnih sila odlučilo na izradu vlastitog linearnog aktuatora. Proračunati su i izabrani elementi potrebni za izradu aktuatora. Isto tako, izabrani su i prigodni senzori sila, kao i kamere kako bi se vizualnim metodama mogle izmjeriti deformacije na sredini uzorka.
Radi potrebe za uranjanjem bioloških tkiva u tekućinu određene temperature, u sredinu kidalice potrebno je postaviti posudu s vlastitim mehanizmom za podizanje, radi jednostavnog uklanjanja i ispiranja nakon ispitivanja. Nakon izrade tih dijelova, potrebno je kidalicu postaviti na postolje izrađeno od aluminijskih profila. Za kraj konstruiranja osmišljeni su zaštitni poklopci za pokrivanje bitnih dijelova kidalice.
Provedena je i numerička analiza nosive konstrukcije, analitički te numerički u programskom paketu Abaqus CAE. Također, provedena je numerička analiza sklopa aktuatora i nosive konstrukcije, pri čemu je za opterećenje aktuatora korištena maksimalna aksijalna sila od 2kN te vremenski promjenjiva sila u rasponu od 0 do 2kN.

Abstract (english)

In this paper, a biaxial testing machine for the static and low-frequency dynamic tensile testing of biological tissues and soft polymer materials is developed and constructed.
The theoretical part of the paper describes static tensile testing as well as ways of measuring deformations with visual methods. Some of the already existing biaxial testing machines used for this purpose are enumerated and describer, with special reference to the different gripping mechanisms depending on the material being tested.
Available electromechanical actuators on the market, which would be required for this purpose, were studied and because of their small carrying capacity of transverse forces, it was decided to make our own linear actuator. The necessary parts for the construction of the actuator were calculated and selected. Also, suitable force sensors, as well as cameras were selected so that the deformations in the middle of the sample could be measured by visual methods.
Due to the need to immerse biological tissues in a liquid of a certain temperature, it is necessary to place a container with its own lifting mechanism in the middle of the testing machine, for it to be easily removed and rinsed after testing. After making these parts, it is necessary to place the testing machine on a stand made of aluminum profiles. Also, protective covers have been designed to cover the essential parts of the tensile testing machine.
Numerical analysis of the construction was carried out, both analytically and numerically in the Abaqus CAE software package. Also, the numerical analysis of the actuator in assembly with construction was carried out, whereby a maximum force of 2kN and a time varying force in the range of 0 to 2kN were used for the axial load of the actuator.

• Keywords: statičko ispitivanje materijala; dvoosna kidalica; linearni elektromehanički aktuator; metoda korelacije digitalne slike; prihvati
• Keywords (english): static material testing; biaxial testing machine; linear electromechanical actuator; digital image correlation method; grips
• Language: croatian
• URN:NBN: urn:nbn:hr:235:995295
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-05-07 09:18:38