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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Softwarové rozhraní pro uživatelské aplikace laser trackeru / A software interface for a laser tracker user application

Kozáček, Peter January 2015 (has links)
For assembly of product machine is necessary to evaluate a geometric accuracy of individual functional parts of the machine. This process is very demanding and time consuming. One of the reasons of mentioned problems is the lack of software (adaptation) for measuring of the accuracy of geometrical precision. This theses (diploma work) focuses at facilitating the development and creation of own application based on customer requirements and for measuring geometric accuracy with the Laser Tracker AT901 from Leica company. The aim is to create a basic application suitable for measurement of geometric accuracy, which would speed up this process, would be user-friendly, simple and open for further expansion.
2

Predikování vybraných vlastností rotačních kinematických dvojic obráběcích strojů / Prediction of Selected Parameters of Rotational Kinematics Pairs of Machine Tools

Marek, Tomáš January 2019 (has links)
The dissertation thesis is used as a methodology for prediction of selected parameters of rotational kinematic pairs of machine tools. The motivation for its writing has been continually increasing requirements for parameters (performance, accuracy, static and dynamic stiffness) of machine tools. The methodology takes into account the availability of suitable measuring devices and description of the design of rotary kinematic pairs. It will be useable for predicting the behavior of rotational kinematic pairs, even at the design stage by applying results to the machine design. The work is processed so that first is used a system approach to suggest methodology for prediction of the behavior of rotary kinematic pair in CNC machine tools, planning measurement strategy and verifying the results, including applications for specific kinematic chain of the selected machine. Based on this system approach and the resulting methodology, the measurement of the rotary kinematic pair was performed. The results of the system approach and measurement are generalized in the form of recommendations for designers of machining centers, allowing to increase the accuracy of the rotational kinematic pair.
3

Mapování geometrických chyb v pracovním prostoru obráběcího stroje / Mapping geometry errors in the machine tool workspace

Knobloch, Josef January 2011 (has links)
Diploma thesis offers a new approach to the measuring of geometry errors in the machine tool workspace with the aid of laser tracker. There is a method of data acquisition and also the Matlab programs for data processing suggested in the thesis. This method can determine the accuracy and repeatibility of positioning and angular displacement of the numerical controlled axes of the measured machine tool and it compiles its mathematical model. All the gathered knowledge is used to evaluation of geometric accuracy of the virtual machined workpiece.
4

Měření vřeten obráběcích strojů pomocí bezkontaktních snímačů / Measurement of machine tool spindles by means of non-contact sensors

Slavíček, Josef January 2013 (has links)
The goal of this work is to propose a suitable methodology for measuring and evaluating the geometric precision of spindle rotation. Identification and classification of errors while moving spindle. Part of this work should be also a program in LabVIEW that evaluate the errors in the motion of the spindle. Practical functionality of the proposed measurement system should be tested at selected MCV754 QUICK machines, lathes SV 18 and milling machine FNG 32. For processing of the results should be used basic statistical procedures. This thesis includes research in the field of machine tool spindles and different ways of measuring spindle motion deviations from the ideal path. There is also included the effect of sensors to measuring spindle running accuracy and identification of suitable sensors applicable for this application. There is a proposal of measurement of selected machinery, and defines all the components required for measurements that were used during spindle running precision measurement. Part of this work is a basic description of the program developed for evaluating errors in the motion of the spindle.
5

Analýza příčin zmetkovitosti při výrobě ložiskových kroužků valivých ložisek / Root cause analysis of scrap during production of bearing rings in a roller bearing company

Studýnka, Pavel January 2017 (has links)
This diploma thesis concerns about measuring of rings of bearings from the input material, throughout machining processes, such as turning, heat treatment, grinding, till finishing operations as honing. Purpose of this thesis is to map all the processes in a roller/needle bearing company, measuring of rings of bearings, evaluating data, propose actions leading to decrease the number of scrap product and technical-economical evaluation of changed processes.
6

Testování technologie on-the-fly přístrojem LaserTRACER / Testing technology on-the-fly instrument LaserTRACER

Vala, Michal January 2017 (has links)
This diploma thesis describes realization and testing on-the-fly measurement using tracking interferometer. This measurement enables to achieve higher amount of measured points and decrease time of machine tool calibration. Calibration and verification values of machine parameters, as well as time of measurement and other details of this method are compared with results of conventional method called trigger. To evaluate the quality of volumetric compensation created from calibration values, we use verification measurement of circular interpolation.
7

Měření obrobků na obráběcích strojích pomocí obrobkové sondy / Measurement of workpieces on machine tools using a touch probe

Velič, Samuel January 2020 (has links)
This diploma thesis deals with the influence of electronic compensation on accuracy of the measurement using the touch probe. The theoretical part concerns touch probes, specifically their classification, principles of working and applications. This part also includes devices used later in the experiment, particularly double ballbar, laser interferometer and LaserTRACER. The Practical part describes an experiment, demonstrating the correlation between the accuracy improvement of the touch probe and the electronic compensation’s level. All measurements were executed in accordance with the norm VDA 5 and were evaluated by the Matlab software. The graphs of reliance tolerance of capability of measurement on the length of the benchmark. At the end of this diploma thesis there are partial conclusions deduced. The deduction is based on generated graphs. The partial conclusions synoptically compare the influence of individual machine´s configurations on the accuracy of the touch probe.
8

Návrh automatického cyklu pro posuzování způsobilosti měření obrobkovou sondou na obráběcím centru / Design of an automatic cycle for assessing the measurement capability of a workpiece probe on a machining center

Mišún, Filip January 2021 (has links)
This diploma thesis describes the procedures of individual electronic compensations for CNC machines used to increase the accuracy of machines. This part is followed by the determining tolerance of the measuring and the influence of individual electronic compensations based on measured data using touch probe and calibrated standards according to VDA 5 norm.
9

Data-Driven Process Optimization of Additive Manufacturing Systems

Aboutaleb, Amirmassoud 04 May 2018 (has links)
The goal of the present dissertation is to develop and apply novel and systematic data-driven optimization approaches that can efficiently optimize Additive Manufacturing (AM) systems with respect to targeted properties of final parts. The proposed approaches are capable of achieving sets of process parameters that result in the satisfactory level of part quality in an accelerated manner. First, an Accelerated Process Optimization (APO) methodology is developed to optimize an individual scalar property of parts. The APO leverages data from similar—but non-identical—prior studies to accelerate sequential experimentation for optimizing the AM system in the current study. Using Bayesian updating, the APO characterizes and updates the difference between prior and current experimental studies. The APO accounts for the differences in experimental conditions and utilizes prior data to facilitate the optimization procedure in the current study. The efficiency and robustness of the APO is tested against an extensive simulation studies and a real-world case study for optimizing relative density of stainless steel parts fabricated by a Selective Laser Melting (SLM) system. Then, we extend the idea behind the APO in order to handle multi-objective process optimization problems in which some of the characteristics of the AMabricated parts are uncorrelated. The proposed Multi-objective Process Optimization (m-APO) breaks down the master multi-objective optimization problem into a series of convex combinations of single-objective sub-problems. The m-APO maps and scales experimental data from previous sub-problems to guide remaining sub-problems that improve the solutions while reducing the number of experiments required. The robustness and efficiency of the m-APO is verified by conducting a series of challenging simulation studies and a real-world case study to minimize geometric inaccuracy of parts fabricated by a Fused Filament Fabrication () system. At the end, we apply the proposed m-APO to maximize the mechanical properties of AMabricated parts that show conflicting behavior in the optimal window, namely relative density and elongation-toailure. Numerical studies show that the m-APO can achieve the best trade-off among conflicting mechanical properties while significantly reducing the number of experimental runs compared with existing methods.

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