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5-axis machining operations bring new challenges for predicting cutting forces. Complex tool workpiece engagements and tool orientations make it difficult to adapt 3-axis process models for 5-axis operations. A new model is developed to predict cutting forces with arbitrary tool/workpiece engagement and tool feed direction. A discretization approach is used, in which the tool is composed of multiple cutting elements. Each element is processed to determine its effect on cutting forces, and global forces are determined by combining the elemental effects. Cutting tests are conducted to verify force predictions, where the tool/workpiece engagement is provided through a geometric software application. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes an algorithm that predicts the shape of material removed by a flat-end milling tool, and this may be used to compute machining strip width and scallop height at different positions of the tool path track. The algorithm computes swept sections, profiles which are swept by a moving tool bottom by passing through given planes. The technique is applicable for finish and semi-finish multi-axis milling strategies that use flat-end tools. For these strategies, the algorithm complexity can be reduced from computation of the 3D envelope of swept volumes to computation of plane-circle intersections. A new adaptive derivative-free method to sample tool motion provides robust means to generate intermediate tool positions. The step length is constrained by and dependent on different geometrical measures. At each point of a tool path, in the plane perpendicular to the cutting direction, the bottom profile of the swept section is an estimate of the profile of material left. By calculating the distance between part geometry and the computed profile of removed material, machining strip width and a scallop profile can be derived. These results can be used by tool path generation and validation routines to accurately determine the step-over between tool path tracks and surface quality. [Copyright &y& Elsevier]

Abstract: This paper describes the development of a five-axis tool path generation algorithm for the machining of complex shaped parts using flat-end tools. In order to reduce the machining time and to ensure optimal quality, the step-over is optimized in each tool contact point. This step-over calculation is obtained through the integration of a newly developed algorithm for material removal simulation. The latter is performed by calculating swept volumes which represent tool motions interpolated according to the machine kinematics. The developed algorithm has been implemented for contour like (spiral) strategies and validated through the machining of an industrial example. [Copyright &y& Elsevier]