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Minimization of tool path errors in high speed machining necessitates optimal design of machine tools and application of advanced control strategies. Analytical models that accurately represent interactions between the machine tool, workpiece and cutter prove necessary to accomplish these tasks. Two distinctive methods of modeling, suitable for the design of mechanical hardware and advanced control systems, are presented. One of these methods is highly intuitive and allows interactive model building [1]. The other method is more accurate and comprehensive but does not provide easy insight into the model development process and requires advanced software for performing symbolic computations [2]. Together, these methods form the basis of a systematic and stepwise modeling methodology and environment, and provide information needed for optimal design of a wide range of machine tools.

Structural dynamics of machine tools causes deviations between the actual and NC programmed tool paths. These deviations, often negligible in traditional cutting, can become the major cause of errors in high speed machining. This paper presents new methods for: (1) model based assessment of the dynamic performance of machine tools, and (2) derivation of analytical models representing the structural dynamics. The assessment is accomplished by combining measurements obtained by means of the Heidenhain Cross Grid and multi-component, wide bandwidth accelerometers. The proposed performance assessment and modeling methods are illustrated by examples obtained for various machines at different feed speeds.