A Feed-Direction Stiffness Based Trajectory Optimization Method for a Milling Robot

The post-processing process for an industrial robot in milling applications suffers from a redundancy problem when converting a 5-axis tool path to the corresponding 6-axis robot trajectory. This paper proposes a feed-direction stiffness based index to optimize the redundant freedom of the robot after identifying its stiffness model. At each cutter location point, the stiffness of the robot machining system along the feed direction is maximized, and an optimal robot configuration is obtained. The optimized robot trajectory via the proposed method has an advantage of improving the machining stability and production efficiency. Experiments verify the validity of the method.

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