Razvoj mikrohvatača pogonom od NiTi memorijske žice

master's thesis

• Title (english): Microgripper design based on NiTi memory shape wires
• Author: Karlo Kerto Grbić
• Mentor: Zoran Domitran (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2022-07-20, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Precision Mechanical Engineering

Abstract

Sve intenzivniji razvoj različitih područja vezanih uz sofisticirane industrijske procese na mikrorazini postavlja nove zahtjeve na konstrukcije visoke preciznosti i točnosti. Zbog toga se javljaju potrebe za razvojem takvih mikrohvatača kod kojih je zračnost eliminirana u najvećoj mogućoj mjeri. U tu svrhu mogu poslužiti mehanizmi s podatljivim zglobovima. Kroz rad je dan pregled postojećih područja primjene mikrohvatača te njihova uloga u sferi mikrosustava. S obzirom na konstrukcijske izazove prilikom kreiranja takvih rješenja, potrebno je uzeti u obzir posebne paradigme razvoja proizvoda na malenoj razini imajući na umu modeliranje konstrukcije za aditivnu proizvodnju. Zbog svega toga, poseban je naglasak stavljen na proučavanje aktuatora za navedene primjene i materijala pogodnog za 3D tisak. Konstrukcijski dio rada započinje odabirom metode kreiranja mikrohvatača kao podatljivog mehanizma. U tu je svrhu korišten model transformacije krutih tijela za koji su stvorene tri inačice mehanizama prikladnih za ostvarivanje zadanog pomaka te je provedena kinematička analiza kako bi se odredila najpovoljnija. Računalni model za analizu i provedba simulacija ostvareni su u programskom paketu MSC Adams te je dobivena analiza pomaka i gibanja svakog mehanizma prilikom čega su isti ugođeni, to jest definirane su njihove konačne dimenzije. Drugi dio rada usredotočuje se na proračun odabranih elastičnih zglobova koji su prethodno raščlanjeni kako bi se proračunavao prikladan oblik zgloba. Korišteni su kružni i prizmatični elastični zglobovi koji su zamijenili rotacijske članove mehanizma. Dimenzioniranje zglobova napravljeno je pomoću programa detasFLEX koji za numerički proračun koristi MATLAB. Usporedbom s analitičkim jednadžbama za kružne zglobove potvrđena je točnost te metode. Na kraju je modeliran sklop mikrohvatača uzimajući u obzir pretpostavku o izradi procesom aditivne proizvodnje. Sam model mikrohvatača konačno je načinjen postupkom 3D tiska te prikazan na fotografijama uz predočavanje stvarnog hoda.

Abstract (english)

The proliferation of diverse domains associated with sophisticated industrial processes at the micro level place new demands on high-precision design. For this reason, there is a need for the development of microgrippers whose clearance is eliminated to the greatest degree possible. For this purpose, mechanisms with compliant joints can be implemented. In the paper an overview of the existing areas of application of microgrippers is given, as well as their role in the field of MEMS. With regard to design challenges in a process of generating mentioned solutions, one ought to consider special paradigms of product development on a small scale and moreover have in mind design for additive manufacturing. Consequently, particular emphasis is placed on review of actuators for given applications as well as several materials relevant for 3D printing. The design process begins with the selecition of the method for creating a microgripper as a compliant mechanism. For that purpose a rigid-body replacement method is used, where three variants of suitable mechanisms were generated after what kinematic analysis was conducted in order to determine the adequate one. Simulation model and numerical analysis were carried out in MSC Adams software thus the data of displacement and motion was gathered. During the first phase, all of the mechanisms were fine-tuned and thus their dimensions were defined. The subsequent part of the paper is focused on the dimensioning of flexible hinges which were formerly analyzed therefore acquiring optimal choice of hinge geometry. Circular and corner-filleted contours were utilized as substitutes for revolute joints. Calculations of hinges' parameters were conducted through detasFLEX program based on numerical computations in MATLAB. A comparison with the analytical approach for circular hinges confirmed the accuracy of the method. Latterly assembly of microgripper was modeled considering the assumption regarding design for additive manufacturing. The physical model itself was created via 3D printing techniques and presented on photographs with the representations of the stroke.

• Keywords: mikrohvatač; podatljivi mehanizam; elastični zglobovi; preciznost i točnost; zračnost; aditivna proizvodnja
• Keywords (english): microgripper; compliant mechanisms; flexure hinges; precision; clearance; additive manufacturing
• Language: croatian
• URN:NBN: urn:nbn:hr:235:824415
• 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: Embargoed access; Embargo expiration date: 2024-07-13
• Created on: 2022-07-13 07:57:01