针对目前普遍使用的组合式凸轮轴凸轮表面微裂纹特征，采用跑道形线圈设计制作差动激励涡流探头，运用COMSOL软件仿真分析线圈间距、提离、圆弧凸面曲率半径等对裂纹检测信号的影响，获得了最优的差动激励涡流检测探头参数；然后根据凸轮轮廓特点，设计了三自由度探头跟踪机构，并搭建了基于该机构的无损检测实验平台进行检测性能的评价；最终根据实际大批量、高速、高精检测的需求，完整设计了凸轮轴自动化涡流检测系统，制定出高速、高精自动化的检测工艺，检测效率为30 s/件，最小检测深度为0.1 mm。

Aiming at detecting microcrack of the cam surface, the differential eddy current sensor was designed and made up by race track coils. And the COMSOL software was used to simulate and analyze the influence of coil spacing, lift-off, and curvature radius of the convex surface on crack signals. Then the optimal differential eddy current sensor parameters were obtained. According to the characteristics of the cam profile, the three-degree-of-freedom self-following structure was designed, and a flaw detection platform based on this structure to evaluate the detection performance was established. Finally, in order to meet the large-volume, high-speed and high-precision testing requirements in real industry, the whole camshaft automatic eddy current detection system was designed, and meanwhile a high-speed and high-precision automatic detection process was developed, in which the detection speed is 30 s/piece and the minimum detection depth is 0.1 mm.