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Pocket milling is an essential issue in rough milling. Although machining capacities have been strongly modified, no significant evolution was observed about pocket milling trajectories. Trochoïds and plunge milling are new types of strategies which have found practical applications in hard materials rough milling. This paper aims at evaluating their potential in rough pocket milling of aluminium alloys. Algorithms were developed to generate trochoïdal and plunge cutting trajectories for pocket milling, with cycle time optimisation regarding to milled surfaces quality. An experimental campaign has also been done and focused both on productivity and quality issues. Two different high speed milling machine tools were tested: a serial three-axis machine tool and a parallel kinematics five-axis machine tool. The results of this work leads to a better definition of the strengths and weaknesses of trochoïdal milling and plunge cutting strategies in aluminium alloys rough machining with the focus to optimize the choice of strategies. [ABSTRACT FROM AUTHOR]

This paper presents a study of the tool path adaptation to the HSM machining process. The definition of an efficient process imposes the common selection of the milling method and of the cutting conditions. Concerning the tool path programming, the user must choose a milling method and an algorithm dedicated to the part to be machined. The computed tool path does not introduce a reduction of the productivity by appearance of perturbations on the kinematical behaviour of the machine tool and on the mechanical behaviour of the tool. To reduce the influence of the perturbations, CAM software proposes many solutions and options. It is then difficult to choose and to define a machining operation. After an analysis of difficulties due to such part, we present a problem classification. According to the requirement, such classification simplifies the choice of the machining method. [ABSTRACT FROM AUTHOR]

While improving the dynamical performance of a flexible motion control system, additional stresses are generated which induce undesirable vibrations. The design of adequate control algorithms makes it possible to enhance the overall behaviour of the machine while limiting its deformation modes vibrations. This paper presents a comparative study of the influence of different control algorithms on the trade-off between the cycle time and the amplitude of the residual vibrations, which have been applied to a Cartesian robot. While this selection of control algorithms is not exhaustive, these can all easily be implemented in current industrial systems. Each selected control algorithm is analysed along with experimental validations. [ABSTRACT FROM AUTHOR]

Functional tolerancing requires calculating the influence of all the deviations admitted on the parts by their definition drawings according to ISO standards' to check the respect of the functional requirements. The method CLIC (Tolerancing in Localization with Influence of the Contacts) includes algorithms of choice of the specifications, an original and complete 3D method of calculation of the result based on the "analysis lines", at worse cases and in statistic, and a method of synthesis of the tolerances. This paper presents the influence of the deviations of a junction on the requirement and the decomposition of a complex requirement in sub-requirements. A three-dimensional statistical application is proposed with a presentation of the worksheet Microsoft EXCEL. [ABSTRACT FROM AUTHOR]