Abstract
A new version of the remote control impact acoustic tester for the climbing robot "Rising Cross" has been developed. This Rising Cross is a robot which climbs and tests concrete structures. The previous impact acoustic tester for "Rising Cross" was not powerful enough and its acoustic acquisition was not high tolerance enough with respect to noise. The accuracy of the tester was also affected by the noise of the suction cups. Therefore it couldn't detect actual defects due to the noise of the suction cups which were equipped to "Rising Cross." All three of these problems have been addressed. So a new impact system and a new acquisition system were developed. The new impact system has a linear motion impactor powered by a spring which creates an impact forty times greater than the previous impactor. In addition, the new acoustic acquisition has four microphones and is able to reduce noise by averaging the four signals obtained through the four microphones. As for the suction cups, we replaced the previous type with suction cups that have the motors covered. This version of Rising Cross successfully inspected an artificial circular void defect with a diameter of 200 mm at a depth of 25 mm in a concrete wall.
