Microwave Antenna Sensors for Fatigue Crack Monitoring Under Lap Joints

This paper presents a microwave antenna sensor that has the ability to monitor fatigue cracks between lap joints where compressive force is present or in any other areas where a crack is hidden between two parts of a structure. The sensor is designed to be low profile, light weight, and conformal, making it ideal for aerospace applications where lap joints are a common design feature, and thus minimizing manual inspection times. The design of the fatigue sample for simulating a lap joint will be presented. The experiment results validated the microwave antenna sensor’s capability to effectively monitor fatigue cracks under lap joints.