Computer Integrated Manufacturing - Research Topics

PMA’s research activities in the domain of "computer integrated manufacturing" focus on the development of advanced CAD/CAM & NC-programming tools for the design and manufacturing of complex shaped surfaces. Specific research topics focuses on reverse engineering, tool path generation strategies for multi-axis milling, process planning tools for the machining of complex shapes by multi-axis milling and collision free NC-programming through the integration of tool path generation and machine simulation.

• CAD/CAM, process and production planning
• CAD Modelling
• Tool Path Generation & NC-Programming
• Process & Operations Planning
• Production Planning
• NC-Controls

CAD/CAM, process and production planning

Information technology enhances productivity and creates new opportunities for the manufacturing environment. Powerful tools such as CAD/CAM/CAPP support the entire process from design to manufacturing. Research topics at our department cover the broad area of product modelling, process planning, tool path generation and NC-programming, production and shop floor planning.

CAD Modelling

Research on CAD modelling mainly focuses on Reverse Engineering, which aims at generating a mathematical CAD model from a physical shape by its measurement data obtained through 3D CMM (coordinate measurement machine) or medical imaging techniques. Our expertise covers suited digitisation method selection, distributed point cloud processing, faceted model handling and parametric NURBS surface generation.

Tool Path Generation & NC-Programming

Research on tool path generation is mainly focused on multi-axis machining of complex shaped parts, using conventional multi-axis machines as well as robots and parallel kinematic structures (PKS). Multi-axis milling tool path generation algorithms dynamically optimise the tool orientation and the feed direction for maximal material removal and optimal surface finish. These algorithms, in a first phase developed for NURBS models, have been adapted in a later phase for faceted models (STL). Problems of collision between the machine and the workpiece are solved by the integration of machine simulation software with either the NC- postprocessor or directly with the tool path generation module (CAM). Feature based tool path methods have been developed for various EDM operations and follow up-coming standards like STEP-NC.

Process & Operations Planning

Research on process and operations planning covers several manufacturing processes for making complex shaped products. Suitability analysis of CAD models for manufacturing purposes aims at analysing the mathematical description of the product shape in relation to the information needed for the automatic operations planning. Feature based technology and manufacturing driven geometrical analysis methods belong to the subjects within this research. Research in the area of milling focuses on the evaluation of several multi-axis cutting strategies Dynamic model segmentation methods, appropriateness checks of multi-axis operations vs. 3- axis operations and set-up dependent information retrieval are investigation topics herein. Advanced rough milling techniques for complex shaped cavities are enabled by intermediate surface generation algorithms based on 3D morphing. New OR (operations research) and AI (Artificial Intelligence) based algorithms have been developed for optimal bend sequencing and appropriate tool geometry selection for complex sheet metal parts. Machining strategies are being developed for incremental forming, a process where a sheet metal is progressively formed by a rotating cylindrical tool. Processing windows and feature based process planning tools are also developed for various electrical discharge machining (EDM) processes (die sinking, EDM milling, …).

Production Planning

Research on computer aided production planning focuses both on the integration with process planning and on the development of more efficient production planning algorithms. A first study covers the integration of production planning and process planning for a single machine, having sequence dependent setups as a typical feature. Several algorithms and schemes have been designed and tested to develop an integrated planning. Another study focuses on the integrated production planning within a production cell. Dealing with multiple processes, each having its own optimisation criteria, an efficient way to come to an integrated production plan is sought.

NC-Controls

Next generation NC-control systems with feature based and tool path generation functionality are being developed. The input of a feature based NC-control system consists of machining tasks such as milling of pockets or drilling/tapping of holes. Detailed tool paths are directly generated at controller level. Integration of machine simulation functionality enables collision-free NC-programming.