Optimized feed scheduling in three axes machining Part II: Experimental validation

The optimized feed scheduling strategy, developed in part I of this paper, considers an optimal use of the feed drive systems. The low frequency dynamics of the different feed drive systems of the machine tool are identified. The resulting transfer functions are transformed into FIR filter and integrated with the planning of the tool trajectory. The effectiveness of the proposed feed scheduling strategy is demonstrated using ball end milling of a workpiece that provides variable cutting conditions along a nonlinear tool path. The performance of this strategy in terms of productivity, machining safety, and machining accuracy, is compared to a feed scheduling strategy based on control points. The proposed strategy has significantly improved the tracking and trajectory following characteristics. It achieves a good prediction of the feed rate of the different axes and consequently a better regulation of the cutting force. In addition, by increasing the feed rate, while respecting the different constraints, it improves the tool path accuracy and enhances the productivity.