Abstract
This paper presents a card-type acoustic emission wave (AE) sensor with symmetrically four-beam structures and thermal actuators providing normal enhanced forces to increase signal-to-noise ratio (SNR). The enhanced force applied to the sensing beam can be observable by thermal imager. The location of AE source can be detected by this developed single sensor, greatly improving the conventional method using multiple AE sensors and large installation area. Distinguishing the health and injured elbow joints is also demonstrated.