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This paper studies the dynamic feedrate control problem for mechanical stages performing contouring actions. In modern researches, feedrate is considered as a dynamic factor instead of simple constant value in the traditional methods, and should be properly controlled to meet higher precision standard nowadays. To incorporate the dynamic feedrate in the path interpolation, the so called non-uniform rational B-spline (NURBS) algorithm is utilized to form the fundamental real-time interpolation structure of this research. The result of a sophisticated intelligent feedrate control design is then proposed where the system feedrate is real-time determined based on both the feedback of the path curvature and the measured contour error. Experiments and comparative studies for free-form paths are also conducted where the results show that the proposed design indeed can provide significant precision improvement in overall contouring performance in contrast to the traditional method. Therefore, the effectiveness and the goal of the proposed method can be verified which suggests that the entire scheme has the potential for real industrial applications.

This paper proposes a novel feedrate control scheme utilized in real-time non-uniform rational B-spline (NURBS) interpolation algorithm for the contouring control purpose. The objective is to improve the contour error performance to achieve high-precision standard. The proposed structure can provide the action that once the contour error is large in the relative sense, then the feedrate will be adequately reduced to provide sufficient time for controller to settle. By real-time adjusting the feedrate, contour error will not accumulate such that the precision can be effectively improved. Experiments are conducted to validate the effectiveness of the proposed method and comparison with other control methods is also arranged. All the obtained results indeed demonstrate the effectiveness of this method.

This paper proposes a novel feedrate interpolation strategy depending on the error feedback information. The proposed strategy incorporates the real-time non-uniform rational B-spline (NURBS) algorithm and is applied in a biaxial contouring stage system. The objective of the strategy is to improve the contouring accuracy to cope with the high-precision standard nowadays. The proposed method does achieve the control purpose that if the detected contouring performance is beyond a given specified value, then the feedrate controller will vary the actual feedrate to provide better contouring accuracy. By real-time adjusting the feedrate depending on the error feedback, contouring error will not accumulate such that the precision can be improved. Many experiments are conducted and the results do show the effectiveness of the proposed method.