Flexible cam profile synthesis method using smoothing spline curves

This paper describes a synthesis method of designing flexible cam profiles by using smoothing spline curves. Our approach simultaneously considers displacement, velocity and acceleration rather than displacement alone in the design process. The inherent characteristic of the smoothing spline ensures the smoothness of cam profiles designed by the proposed method. The essential difference between the proposed method and other existing approaches is that our method allows designers to refine the cam motion by local modifications while still satisfying profile smoothness and discrete constraints. Particularly, the method can control not only the level but also the shape of the velocity and acceleration curves for better kinematical and dynamic properties. Examples show that the obtained cam profiles provide solutions for some problems in automotive engine valve trains.

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