Floating Ultrasonic Transducer Inspection System and Method for Nondestructive Evaluation

NASA's Langley Research Center has developed a Floating Ultrasonic System for improved nondestructive testing. Most ultrasonic scanners require an external liquid coupling agent (e.g., water, gel, oil) to make a good contact between the probe and the surface being scanned; however, some surfaces are sensitive to moisture and/or contamination created by these agents. NASA created the Floating Ultrasonic System to address this issue. NASA's technology is based on a momentary touching scheme where a vibrating probe comes in contact with the structure for fractions of a second while performing measurements, giving the probe the appearance of floating across a surface. The design allows for the easy movement of the probe over surfaces being inspected without the use of a liquid couplant between the probe and the surface. Initial test results have also shown NASA's system to have performance comparable to that of liquid-couplant-based ultrasonic scanners.