Abstract: A defect detection system for thermally imaging a structure that has been energized by sound energy. The system includes a transducer that couples a sound signal into the structure, where the sound signal causes defects in the structure to heat up. In one embodiment, a hard metal disk is positioned between the transducer and the structure to help couple the sound energy from the transducer into the structure. A predetermined force is applied to the transducer and a pulse duration and a pulse frequency of the sound signal are selected so that the sound energy induces acoustic chaos in the structure, thus generating increased thermal energy. A thermal imaging camera images the structure when it is heated by the sound signal.

Abstract: A hand-held sound source for use in an infrared or thermal imaging system that detects sub-surface defects in a structure. The sound source includes a transducer that is positioned against the structure to emit a sound signal into the structure. The sound source further includes an adjustable spring that pushes the transducer against the structure with a predetermined amount of force so that the sound energy is effectively coupled into the structure. The sound source also includes three stabilizing legs that stabilize the transducer on the structure. The length of each leg can be adjustable relative to the length of the other legs so that the sound source can be used against irregular surfaces.

Abstract: A thermal imaging system for detecting cracks and defects in a structure. An ultrasonic transducer is coupled to the structure through a malleable coupler. Ultrasonic energy from the transducer causes the defects to heat up, which is detected by a thermal camera. A control unit is employed to provide timing and control for the operation of the ultrasonic transducer and the camera.

Abstract: A defect detection system for thermally imaging a structure that has been energized by a sound energy. The system includes a transducer that couples a sound signal into the structure, where the sound signal causes defects in the structure to heat up. In one embodiment, the sound signal has one or more frequencies that are at or near an eigen-mode of the structure. In another embodiment, an on-linear coupling material is positioned between the transducer and the structure to couple the sound energy from the transducer to the structure. A predetermined force is applied to the transducer and a pulse duration and a pulse frequency of the sound signal are selected so that the sound energy induces acoustic chaos in the structure, thus generating increased thermal energy. A thermal imaging camera images the structure when it is heated by the sound signal.

Abstract: A thermal imaging system for detecting cracks and defects in a structure. An ultrasonic transducer is coupled to the structure through a malleable coupler. Ultrasonic energy from the transducer causes the defects to heat up, which is detected by a thermal camera. A control unit is employed to provide timing and control for the operation of the ultrasonic transducer and the camera.

Abstract: A system for the thermal imaging of sonically or ultrasonically excited subsurface defects in a structure. The system includes a hand-held sound source, a thermal imaging camera and a control unit. The sound source emits pulses of sound energy into the structure, and the camera generates images of defects in the structure that are heated by the sound energy. The control unit controls the operation of the sound source on the camera for timing purposes. The sound source includes a transducer that is positioned against the structure at a desirable location. The source further includes a pair of legs that are also positioned against the structure to define a plane in combination with the transducer. The length of each leg is adjustable relative to the length of the transducer so that the gun can be used against irregular surfaces. The legs include a rubber tip to further prevent the transducer from slipping on the structure.

Abstract: A system for the thermal imaging of sonically or ultrasonically excited subsurface defects in a structure. The system includes a hand-held sound source, a thermal imaging camera and a control unit. The sound source emits pulses of sound energy into the structure, and the camera generates images of defects in the structure that are heated by the sound energy. The control unit controls the operation of the sound source on the camera for timing purposes. The sound source includes a transducer that is positioned against the structure at a desirable location. The source further includes a pair of legs that are also positioned against the structure to define a plane in combination with the transducer. The length of each leg is adjustable relative to the length of the transducer so that the gun can be used against irregular surfaces. The legs include a rubber tip to further prevent the transducer from slipping on the structure.

Abstract: A thermal imaging system for detecting cracks in a tooth. An ultrasonic dental cleaning tool is used to transmit ultrasonic energy through a jet of water to the tooth that causes cracks in the tooth to heat up. A thermal camera is used to detect the thermal radiation emitted by the heated cracks. The ultrasonic energy is in the form of a pulse where the frequency of the ultrasonic signal is substantially constant within the pulse. The control unit is employed to provide timing and control of the operation of the dental cleaning tool and the camera.

Abstract: A thermal imaging system for detecting cracks and defects in a component. An electromagnetic acoustic transducer (EMAT) is coupled to the component, and introduces pulsed sound signals therein. The sound signals cause the defects to heat up. The IR radiation from the heated pulses is detected by a thermal camera. The amplitude of the pulsed signals are substantially constant, and the frequency of the pulsed signal can be changed within each pulse. A control unit is employed to provide timing and control for the operation of the EMAT and the camera.

Abstract: A thermal imaging system for detecting cracks and defects in a component. An ultrasonic transducer is coupled to the specimen through a malleable coupler. Ultrasonic energy from the transducer causes the defects to heat up, which is detected by a thermal camera. The ultrasonic energy is in the form of a pulse where the frequency of the ultrasonic signal is substantially constant within the pulse. A control unit is employed to provide timing and control for the operation of the ultrasonic transducer and the camera.