Prof. Matthias Weigold
Technical University of Darmstadt, Germany
Hybrid manufacturing – the best of both worlds
Additive manufacturing of metal components provides a freedom of design for heavy duty components that’s otherwise unfeasible. However, precision and surface quality of additively manufactured structures are rarely sufficient for direct application and therefore require subtractive postprocessing steps. This combination of additive and subtractive manufacturing processes is often referred to as hybrid manufac-turing. This paper provides an overview of current research topics in the field of metal based hybrid - additive and subtractive - manufacturing. It furthermore presents the findings of an analysis that identifies research and development efforts in this area on a global level, helping to identify key players and inno-vation drivers.
Prof. Matthias Weigold studied mechanical engineering at Darmstadt University of Technology, Germany, He received the Dr.-Ing. degree in Mechanical Engineering at Darmstadt University of Technology, Germany in 2008. His thesis „Compensation of the tool deformation during machining with industrial robots” was about a new machine tool concept for milling, drilling and deburring applications based on an industrial robot platform.
From 2007 to 2015 he worked at Heidelberger Druckmaschinen AG within the manufacturing division in different functions. As Head of Tool Technology he was responsible for the company-wide development of processes and tool technology and the tool management reorganization. As Head of Engineering he was responsible for the manufacturing innovation management, investment projects and the development and construction of jigs, automation technology and special purpose machines for assembly and manufacturing. He left in 2015 as Head of Engineering and Production Planning for prototype production as well as serial production.
From 2015 to 2018 he worked at SAP SE within the division of Products & Innovation in the field Industry 4.0. As a product owner “SAP Machine Manufacturing Analytics” he was responsible for a new and disruptive product approach of “Internet based Big Data Analytics for Manufacturing Applications”. The interdisciplinary topic of real time data recording, cloud-computing and big data analytics as well as the overall end-to-end integration engineering connects the shop-floor to the global enterprise network. In the last two years, applications for CNC machine tools as well as for industrial robots where developed.
Since January 2019 he is leading the Institute for Production Management Technology and Machine Tools.
Dr. Ondrej Uher
Compo Tech PLUS, Czech Republic
Composite structural parts for high speed machine tools
There are numerous examples of research projects developing composite applications for machine tool industry, like spindles and spindle parts, beams or tools and tooling applications. But there are not yet many successful applications on the market. When developing and researching these composite materials parts usually FEM analysis and extensive experimental verification, like vibration measurement and analysis is applied and usually with great and promising results, but when applied in real machine tool system than the resulting benefit is not as expected. This phenomena is discussed and shown on several examples based on real experience.
Dr. Ondřej Uher born in 1972 in Sušice, Czech Republic, studied Mechanical Engineering at the Czech Technical University in Prague (CTU) and obtained his degree in 1995. He found company Compo Tech Plus spol. s r.o. with his friend, and also CTU student Vít Šprdlík in 1994. Since that he is responsible for all research and development activities relating the main Compo Tech objective to develop and produce composite solution for industrial applications and especially the application in general machine building industry. He received his doctore degree under program of prof. Milan Růžička at CTU in 2003. The close collaboration between Ondřej Uher, CompoTech and CTU is not only the participation on many research projects, which resulted in number of successful composite applications in machine tool and machine building industries, but also in his active role in student education in the field of mechanics of composite materials.
Prof. Pedro Jose Arrazola
Mondragon University, Spain
Predictive modelling of machining processes
Modelling (analytical, FEM, empirical…) of machining process could help reducing the experimental costs and time for implementing new ideas in production plants. The numerical simulation could give an insight of the physical phenomena involved in the machining process and consequently in aspects such as the tool wear, burr formation, surface integrity, stability of the process and so on. This could help reducing the costs of defining the process windows (cutting tools, cutting conditions and so on). However, some aspects should be enhanced before it becomes a common tool used in industry: (i) input parameters identification, (ii) robust models set-up and (iii) validations. In this keynote paper, the latest researches carried out in the field of predictive models development at Mondragon Goi Eskola Politeknikoa (MGEP) will be described. Several modelling case studies developed with a variety of FEM software (Abaqus, AdvantEdge and Deform) and analytical models able to predict not only fundamental variables (forces, temperatures, chip morphology etc.), but also industrial outcomes (surface integrity, tool wear etc.) will be presented. The strategy for input parameters characterization, together with the experimental techniques used to validate the predictive models are also shown.
Prof. Pedro José Arrazola is a Senior Lecturer of Mechanical Engineering and the Head of the Machining Laboratory at Mondragon University. He received his Master degree in Mechanical Engineering at INSA Lyon – France in 1988, and his PhD in 2003 at Nantes University.
He has been active in metal machining during the last 2 decades, publishing 59 papers in international refereed journals (23 papers Q1), 3 book chapters and more than 100 papers in conferences. His H index is 18. He has been awarded with 2 patents (Temperature Measurement in Drilling, On-line Measuring of Component Distortions) and one I.P.R. (Finite Element Model of Chip Formation Process). He has directed the research of 15 PhD and 104 Master thesis and has participated in more than 90 scientific and industrial projects (EU, National and Regional) for several sectors (automotive, aeronautical, railways, medical).
He has been involved as well in continuous training activities related to metal cutting. His current research interests are the following: cutting fundamentals (modeling and advanced experimental techniques), machinability, process monitoring and machining optimization. In recent years, he has focused his research on the machining of aeronautical applications, where analysis of surface integrity condition key aspect.
Prof. Pedro José Arrazola is a Fellow Member of CIRP (The International Academy for Production Engineering) since 2018 (he was Associate Member since 2009). He is as well the secretary of the Scientific Technical Committee of Cutting of CIRP.
Prof. Gabor Stepan
Budapest University of Technology and Economics, Hungary
Exploring the limits of chatter-free high-speed milling operations
Constructed in the space of cutting parameters, the so-called stability lobe diagrams present those domains where chatter-free cutting operations are expected. Unfortunately, the predicted stability charts are very sensitive for the variation of the mechanical parameters in the workpiece-tool-machine structure. Among others, the parameters having relevant effect on chatter are the ones related to the cutting force characteristics, also to the contacts between tool-holder and spindle and between the bearings and the spindle. Accordingly, the mechanical modeling of these parts are considered as possible breakthrough points for the industrial application of the stability charts, which are necessary conditions for achieving parameter regions of high performance. Preliminary calculations of the stability charts predict that specific milling tools can be designed with extreme high efficiency at specific cutting speeds. To reach these parameters, not only the extreme precise modeling is required at the contact tasks, but also specially designed milling tool geometries and dynamically optimized passive and active workpiece fixtures are needed. The lecture will summarize briefly the results achieved in cutting force modeling, tool-holder-spindle contact modeling and spindle bearing modeling together with the corresponding laboratory experiments of model validation and on-line measurement techniques established either for monitoring the cutting processes or to be used in hardware-in-the-loop methodology for tool geometry development.
Prof. Gábór Stépán is professor in Applied Mechanics at Budapest University of Technology and Economics (BME), a position that he has since 1995. His research interests include vibrations and time-delay systems with applications in mechanical engineering, like machine tool vibrations, hardware-in-the-loop experiments, vibrations and stability of robots.
He is member of the Hungarian Academy of Sciences (2001) and the Academy of Europe (2013). He was elected as associate member of the International Academy for Production Engineering (CIRP, 2012) and fellow of the Society for Industrial and Applied Mathematics (SIAM, 2017). He is ERC Advanced Grant holder (2014-2019) with a topic on machine tool vibrations, and the recipient of the Thomas K. Caughey Dynamics Award of ASME (2015). He organized an international advanced course on Dynamics of Machining (2019).