Wyniki wyszukiwania - BazTech

1

Fast and cost efficient measuring of geometry and temperature for open-die forging

Riedel Mirko, Wiese Torben, Hellmich Arvid, Ihlenfeldt Steffen

Journal of Machine Engineering

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2019

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Vol. 19, No. 3

82--93

EN

In open-die forging it is state of the art to use simulation tools for creating forging plans and setpoint values for the forging press and the automated part manipulator. These forging plans define required positions and forces. Therefore, the process can be fully automated. However, even small variations of not considered influence parameters lead to different forging results and thus to a discontinuous process. Influencing factors are, e.g. material parameter deviations, uncertainties in force measurements or variations in the part temperature due to varying environmental conditions. This paper presents an approach for a fully automatic open-die forging process with respect to actual conditions, based on a parallel measurement of the workpiece geometry and temperature and a “process-real-time” adaptation on the controller system. The focus of this work is the development of a measuring strategy and an according sensor setup for the combined temperature and geometry measurement of the workpiece. In addition, the structure, the characteristic features of the components and the beam path of the sensors scanning units are shown. Furthermore, first experimental results for the alignment of the beam path are presented. In the outline, the setup and calibration strategy of the measurement system are stated.

2

The Finite Termination Property of an Algorithm for Solving the Minimum Circumscribed Ball Problem

Gläser A., Grossmann C., Lunze U.

Schedae Informaticae

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2012

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Vol. 21

127--139

EN

In this paper basic mathematical tasks of coordinate measurement are briefly described and a modified optimization algorithm is proposed. Coordinate measurement devices generate huge data set and require adapted methods to solve related mathematical problems in real time. The proposed algorithm possesses a simplified step size rule and finds the solution of the minimum circumscribed ball fitting after only a finite number The iteration is of the steepest descent type applied to the related distance function. But, in contrast to standard algorithms it uses a modified step size rule that takes into account the specific properties of the occurring objective function. This small difference in the code improves the performance of the algorithm and it enables real time use of the proposed method in coordinate measurement machines. The effciency of the prosed algorithm will be illustrated by some typical examples.

3

Ocena dokładności form silikonowych wykorzystaniem pomiarów optycznych

Budzik G., Grzelka M., Markowski T., Oleksy M.

Pomiary Automatyka Kontrola

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2010

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R. 56, nr 1

18-19

PL

Artykuł przedstawia badania dokładności geometrycznej silikonowej formy odlewniczej wykonanej z wykorzystaniem procesu szybkiego prototypowania narzędzi (RT - Rapid Tooling). Badana forma odlewnicza jest przeznaczona do wykonywania prototypów kół zębatych z żywic polimerowych oraz wosków odlewniczych. Celem badań było określenie rzeczywistej dokładności geometrycznej formy silikonowej w stosunku do założeń teoretycznych określonych na podstawie parametrów karty materiałowej zastosowanego silikonu. Forma silikonowa została wykonana na podstawie stereolitograficznego modelu koła zębatego. Do badań wykorzystany został skaner optyczny GOM. Pomiary formy oraz modelu bazowego wykonane zostały w trybie skanującym na podstawie modelu 3D-CAD koła zębatego. Pomiary umożliwiły określenie dokładności wykonania formy w stosunku do nominalnego modelu 3D-CAD. Zagadnienia związane z określaniem dokładności geometrycznej form silikonowych i wykonanych w nich prototypów są poruszane sporadycznie w analizowanej literaturze z zakresu szybkiego prototypownia. Z tego względu badania przedstawione w artykule stanowią oryginalne opracowanie w aspekcie teoretycznym i praktycznym.

EN

The paper presents investigations of the geometrical accuracy of a silicone casting form manufactured with use of the rapid prototyping of tools (RT - Rapid Tooling). The tested casting form is applied to production of prototypes of sprockets from polymer resins as well as casting waxes. The aim of investigations was to determine the real geometrical accuracy of the silicone form in the relation to the theoretical assumptions taken on a basis of the parameters of the used silicone material card. The silicone form was made basing on the sprocket stereolitographic model. An optical scanner GOM was applied to investigations. Measurements of the form and base model were taken in the scanning mode on a basis of the sprocket 3D-CAD model. They enabled determining the precision of the form manufacturing in relation to the nominal 3D-CAD model. Problems deal-and prototypes manufactured in them are seldom considered in the literature from the field of rapid prototyping. That is why the investigations presented in the paper are the original work from theoretical and practical point of view.

4

Application of rapid prototyping - SLA, FDM - to manufacture model of aircraft wheel hub

Śliwa R. E., Budzik G., Bernaczek J.

Journal of KONES

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2010

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Vol. 17, No. 3

423-429

EN

Implementation of prototypes of the aircraft is a complex process - which requires a series of operations on data preparation, maintenance and inspection of the measuring apparatus. The development overlooks the stage of design and CAD modelling which is the subject of separate publications, and presents only issues related to the RP process - the SLA and FDM. Special attention was paid to the need to properly export to CAD models as STL and subseąuent analysis of the surface after tessellation (preview generated triangle mesh describing the model). The process of preparing data in dedicated utility software is a key step for the correct implementation of the prototype aircraft wheel hub. The correct position of the working models on the platform, generated automatically supports editing and verification output files (simulation analysis of overlapping layers) minimizes the risk of damage during the prototyping process itself as well as the subsequent finishing. The final chapter presents the coordinate measuring of made prototypes that will help identify areas of application methods of RP in the aerospace industry. Prototype SLA is marred by a higher error than the FDM model but allows for effective finishing operations, which eliminates the geometric errors and significantly improves the quality of the surface.

5

Determining errors in complex surfaces machining with the use of CNC machine tools

Werner A., Poniatowska M.

Archiwum Technologii Maszyn i Automatyzacji

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2006

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Vol. 26, nr 2

211-217

EN

The present paper concerns the question of determining errors in the process of producing parts with the use of CNC machine tools in order to introduce intermediary (off-line) correction of the processing programme. The elements were processed with a CNC FYS I6N milling machine with a TNC 360 Heidcnhain numerical control system. The methodology of determining the errors was presented on the example of an object made from an aluminium alloy described with a free surface panel. Both the geometrical model and the processing programme were created in the Mastercam system. The production accuracy inspection were conducted on a MISTRAL Brown & Sharpe coordinate measuring machine. The obtained information relating to the values and distribution of processing errors was used to correct the CNC machine tool control programmes.

PL

Artykuł dotyczy zagadnienia wyznaczania błędów wykonania części na obrabiarkach CNC, co pozwoli na wprowadzenie pośredniej korekcji (off-line) programu obróbkowego. Elementy obrobiono na frezarce CNC FYS 16N z numerycznym sterowaniem TNC 360 Heidenhain. Dokładność wykonania kontrolowano na współrzędnościowej maszynie pomiarowej MISTRAL Brown&Sharpe. Wyniki pomiarów posłużyły do wyznaczenia błędów obróbki. Informacje dotyczące wartości i rozkładu błędów obróbkowych wykorzystane zostały do skorygowania programów obróbkowych.