Research on fractal contact performance of cam surface based on higher-order differential interpolation

Purpose Cam mechanisms are critical in modern automation equipment, but existing cam curve design methods ignore surface micro-features, limiting accurate micro-contact analysis. This study aims to propose a cam curve design method integrating micro-characteristics for precise control of contact performance. Design/methodology/approach A cam curve is established via high-order differential interpolation combined with the W-M fractal function to characterize surface roughness. A modified micro-contact model is developed, and the control variable method is used to analyze the influence of high-order interpolation nodes (displacement, velocity and acceleration) on contact performance. Findings Displacement and acceleration node variations induce unidirectional offset of contact performance extrema, while velocity nodes cause bidirectional offset; the sensitivity order is velocity > displacement > acceleration. The proposed curve enables accurate control of contact performance distribution. Originality/value This study integrates high-order differential interpolation with the W-M fractal function, bridging macro kinematic design and micro-surface characterization, and provides theoretical/methodological support for “contact performance-controllable” cam design.