Franc Čuš

Modeling and adaptive force control of milling by using artificial techniques

The contribution discusses the use of combining the methods of neural networks, fuzzy logic and PSO evolutionary strategy in modeling and adaptively controlling the process of ball-end milling. On the basis of the hybrid process modeling, off-line optimization and feed-forward neural control scheme (UNKS) the combined system for off-line optimization and adaptive adjustment of cutting parameters is built. This is an adaptive control system controlling the cutting force and maintaining constant roughness of the surface being milled by digital adaptation of cutting parameters. In this way it compensates all disturbances during the cutting process: tool wear, non-homogeneity of the workpiece material, vibrations, chatter, etc. The basic control principle is based on the control scheme (UNKS) consisting of two neural identifiers of the process dynamics and primary regulator. An overall procedure of hybrid modeling of cutting process used for creating the CNC milling simulator has been prepared. The experimental results show that not only does the milling system with the design controller have high robustness, and global stability, but also the machining efficiency of the milling system with the adaptive controller is 27% higher than for traditional CNC milling system.

Dynamic neural network approach for tool cutting force modelling of end milling operations

This paper uses the artificial neural networks (ANNs) approach to evolve an efficient model for estimation of cutting forces, based on a set of input cutting conditions. Neural network (NN) algorithms are developed for use as a direct modelling method, to predict forces for ball-end milling operations. Prediction of cutting forces in ball-end milling is often needed in order to establish automation or optimization of the machining processes. Supervised NNs are used to successfully estimate the cutting forces developed during end milling processes. The training of the networks is preformed with experimental machining data. The predictive capability of using analytical and NN approaches is compared. NN predictions for three cutting force components were predicted with 4% error by comparing with the experimental measurements. Exhaustive experimentation is conduced to develop the model and to validate it. By means of the developed method, it is possible to forecast the development of events that will take place during the milling process without executing the tests. The force model can be used for simulation purposes and for defining threshold values in cutting tool condition monitoring system. It can be used also in the combination for monitoring and optimizing of the machining process—cutting parameters.

Sustainable 3D mould design and manufacturing

Development and implementation of scientific tools and principles for designing and manufacturing of sustainable products such as 3D moulds for glass bottles blowing are very important. 3D modelling will be described on the cases of glass products. The mass production industry of glass blowing will be described. CAD and CAM programme will be used for technical documentation-drawings and also for cutting technology planning in moulds machining. CAM (Computer Aided Manufacturing) programme for mould machining will be prepared for application on 3-axial milling CNC machine tool. Specialities as drilling of long bores (vacuum bores) will be explained. Dry and near dry cutting will be included in machining processes as elements of sustainable manufacturing. When all machining operations are done, moulds are checked (dimensions, surface quality, fitting on other tool parts) and when the production of the bottles start, each manufactured product is thoroughly examined.

Advances in Production and Industrial Engineering

This publication, scientific monograph, offers comprehensive chapter series from scientific researchers conducted by regional authors, authorities in the fields and summarizes the principal scientific contributions. The chapters deal with range topics from optimization techniques in production development, quality in production processes, product and process development, technologies for business development and factors of social and economic development. Edited by two editors with contributions from chapters’ authors, this scientific monograph presents advanced topics for students, educators and practitioners. The editors would like to thank all chapters’ authors for devoting of the research results and expertise with the great enthusiasm. We encourage all of them to continue successful highly valuable cooperation, between Faculty of Mechanical Engineering at the University of Maribor and Faculty of Mechanical Engineering at the Ss. Cyril and Methodius University in Skopje.

Object Oriented Approach in Computer Aided Process Planning

Process planning is one of the key activities for product design and manufacturing. Impact of process plans on all phases of product design and manufacture requires high level of interaction of different activities and tight integration of them into coherent system. In this paper, an object-oriented knowledge representation approach is presented with module for parts modeling and module for generation of process plan. Description of machining process entities and their relationships with features, machines and tools are provided. The benefits of the proposed representation, which include connection with geometric model, reduced search space and alternative plan generation, are discussed. These new contributions provide for a new generation of computer aided process planning (CAPP) systems that can be adapted for various manufacturing systems and can be integrated with other computer integrated manufacturing (CIM) modules.