Matthieu Rauch

Tool path programming optimization for incremental sheet forming applications

Incremental sheet forming is an emerging process to manufacture sheet metal parts that is well adapted for small batch production or prototypes. The adjustment time is short, as it is sufficient to modify the tool motions to optimize the manufacturing process. Tool path generation therefore becomes a key topic linked to incremental sheet forming, and process characteristics ask for dedicated tool paths. Hence, this paper first discusses the impact of tool path types and other programming parameters on process implementation through an experimental campaign performed on a parallel kinematics machine tool. Then, a new approach to generate and control Intelligent CAM programmed tool paths is proposed. The major purpose of this innovative concept is to use process constraints for programming and controlling the tool path, which are adapted during the running of the CNC program according to real-time process data evaluation. Validation studies and an industrial implementation are finally presented to assess the efficiency of the proposed approach.

An eXtended Manufacturing Integrated System for feature-based manufacturing with STEP-NC

Computer Numerical Control (CNC) feature-based programming with STandard for the Exchange of Product data model-compliant Numerical Control extends the collaborative model of manufacturing data exchange all along the numerical data chain. This study considers the mutations related to this approach from the manufacturing system level to the industrial enterprise as a whole. The eXtended Manufacturing Integrated System concept is introduced to fill in the gap of the current manufacturing data exchange bottleneck. It is composed of eXtended Computer Aided Design (CAD) and eXtended CNC systems to link the CAD model to the real machined part through the Manufacturing Information Pipeline. The contributions associated with these concepts are demonstrated through a validation platform implemented on industrial CNC manufacturing equipments.

Rough pocket milling with trochoidal and plunging strategies

Trochoids and plunge milling are new types of strategies for pocket milling. This paper aims at evaluating their potential in rough pocket milling of aluminium alloys. After the identification of their trajectory parameters, an experimental campaign is done to compare these new strategies with classical ones. This study focuses on productivity, quality and machine tool dynamics issues.

Five-axis machining: technologies and challenges

Typical applications of 5-axis machining have been found in many industries. However, 5-axis machining still faces a number of challenges. It introduces further complexity as well as flexibility owing to the additional degrees of freedom compared to 3-axis machining. The focus of this review is to provide a perspective view of the research effort towards 5-axis machining that has been carried out over the last ten years. It centres on machine tools including topics such as 5-axis machine tool structures, 5-axis machining tool paths, modelling and compensation of process errors, modelling of 5-axis machine tools and emerging parallel kinematics machines. [Received 18 October 2009; Revised 27 January 2010; Accepted 1 February 2010]

Simulation and optimization in a multi-process environment using STEP-NC

With STEP-NC object oriented programming standard, the next generation of CNC controllers promises to be more open, intelligent and interoperable. This standard totally integrates CNC into the CAD-CAM-CNC numerical chain and is an opportunity to be a common support for various manufacturing processes. New possibilities are offered at the CNC level to make machine tools more autonomous, to perform intelligent part program generation, to increase the productivity and the adaptability in an intelligent multi-process environment. This paper gives a proposal for multi-process manufacturing using STEP-NC as the optimal data model for process planning, process specificities, and inter-processes simulation spaces.

Simulation-based adaptative toolpath generation in milling processes

Milling toolpath is often designed according to a CAD model which is not always an accurate representation of the real part. In an industrial framework, a significant geometrical variability is sometimes observed in parts that belong to the same batch. Therefore, the conventional approach making use of a unique nominal toolpath for manufacturing series of parts fails to confer both geometrical and dimensional conformity to the machined parts. This study explores a strategy for adapting on-line the toolpath thanks to measurements and data driven simulation. An approximation for the actual geometry is derived from data acquisitions and the path is adjusted accordingly. The POD snapshots technique is employed for building up a reduced basis of approximation by considering geometrical features as well as additional parameters (initial setup) for the part. Thanks to its filtering properties, that basis proves to be robust with respect to measurement noise.

Shiphull Welding: Trajectory Generation Strategies Using a Retrofit Welding Robot

Shipbuilding processes involve highly dangerous manual welding operations. Welding of ship hulls presents a hazardous environment for workers. This paper describes a new robotic system, developed by the SHIPWELD consortium, that moves autonomously on the hull and automatically executes the required welding processes. Specific focus is placed on the trajectory control of such a system and forms the basis for the discussion in this paper. It includes a description of the robotic hardware design as well as some methodology used to establish the torch trajectory control.

Advanced programming of machine tools: interests of an open CNC controller within a STEP-NC environment

NC programming still bases upon a heterogeneous and divided CAD/CAM/CNC data chain. Its performances are consequently limited. Tool paths online optimisation is hardly possible. In parallel, emerging new processes like incremental sheet forming or laser additive manufacturing widens the application area of CNC machines. Integrating these processes within intelligent design and manufacturing environments is a great scientific challenge. Meeting these requirements necessitates the use of STEP-NC programming approach (ISO 14649), which benefits from a large support from international industrials and academics. A major interest of STEP-NC is to transfer a large part of the decisions concerning the process implementation to the CNC controller. This paper introduces the advanced CNC programming platform developed at the IRCCyN laboratory, STEP-NC Platform for Advanced and Intelligent Manufacturing (SPAIM). An extension of SPAIM for machines equipped with open CNC controller is proposed as well. These research works are carried out within the FP7 European Project Fofdation.

Milling Tool-Paths Generation in Adequacy with Machining Equipment Capabilities and Behavior

This chapter discusses the challenges associated with tool-paths generation and control for complex surfaces machining. The increase of the technical and economic requirements associated with a diversification of the machining equipment makes it compulsory to implement machine-specific milling strategies to be efficient. Major technological evolutions within this context are identified. Then, advanced CNC programing methods are presented and discussed. Based upon innovative concepts and a new vision of the tool-path generation process, they enable to select the most suitable parameterization. In particular, virtual manufacturing can be of great interest.

Machining simulation – a technical review and a proposed concept model

Machining simulation is a modern tool for safe and reliable machining operations. Geometric simulation is used to mimic the movement during the machining process. Physical simulation is used to discover the ‘sciences’ behind the machining processes, e.g. cutting force, vibration, surface finish, cutting temperature and tools worn. STEP-NC is a new data model for computer numerical control (CNC). It provides rich information for CNC machine tools. The architecture of the NC simulation system based on STEP-NC is proposed in the research, using IDEF0.