United States of America As Represented by the Administrator of Nasa

The United States of America As Represented by the Administrator of the

Other

K Elliott Cramer

William T Yost

Daniel F Perey

William P Winfree

Peter D Juarez

Elizabeth D Gregory

Mool Chand Gupta

Joseph S Heyman

A Ronald Jacobstein

Thomas L Reilly

Harold A Haldren

Joseph N Zalamedia

A method and system for ultrasonic testing of adhesion within a sample, which provides ultrasonic bursts of different frequencies to the sample and maintains a predetermined phase difference between echoes returned from the sample and representative reference signals of the bursts supplied to the sample until a spectrum of the phase differences versus frequency is obtained and from which properties of the adhesion at an interface reflecting the echoes are derivable.

Method for the evaluation of adhesive bond strength via swept-frequency ultrasonic phase measurements

A method of detecting defects in a composite structure includes applying heat to a surface of a composite structure. Thermographic images or frames captured by a moving camera may be utilized to corm temporally aligned images that include temperature data (pixels) from a plurality of frames, wherein the pixels comprise data captured at a simple (uniform) time delay from the time at which heat was applied. The temporally aligned thermographic data for the surface region may include variations due to differences in thermal transients caused by defects in the composite structure. The variations in the thermographic data may be utilized to detect one or more defects in the composite structure.

Method and means to analyze thermographic data acquired during automated fiber placement

A method of detecting defects in a composite structure includes applying heat to a surface of a composite structure. Thermographic images or frames captured by a moving camera may be utilized to form temporally aligned images that include temperature data (pixels) from a plurality of frames, wherein the (pixels) comprise data captured at a simple (uniform) time delay from the time at which heat was applied. The temporally aligned thermographic data for the surface region may include variations due to differences in thermal transients caused by defects in the composite structure. The variations in the thermographic data may be utilized to detect one or more defects in the composite structure.

A method is provided for calibrating ultrasonic signals passed through a crimp formed with respect to a deformable body via an ultrasonically-equipped crimp tool (UECT). The UECT verifies a crimp quality using the ultrasonic signals. The method includes forming the crimp, transmitting a first signal, e.g., a pulse, to a first transducer of the UECT, and converting the first signal, using the first transducer, into a second signal which defines an ultrasonic pulse. This pulse is transmitted through the UECT into the crimp. A second transducer converts the second signal into a third signal, which may be further conditioned, and the ultrasonic signals are calibrated using the third signal or its conditioned variant. An apparatus for calibrating the ultrasonic signals includes a pulse module (PM) electrically connected to the first and second transducers, and an oscilloscope or display electrically connected to the PM for analyzing an electrical output signal therefrom.

Assessment and calibration of a crimp tool equipped with ultrasonic analysis features

An ultrasonic device and method obtains desirable crimp connections between a crimp connector and a wire, or bundle of wires, by assessing the desirability of connections made in a wire-to-wire connection and in other situations where two materials with good acoustic propagation characteristics are joined together via deformation. An embodiment of the device as a crimping tool comprises a compressing means, pulse-generating circuitry, at least one ultrasonic transmitting transducer, at least one ultrasonic receiving transducer, receiving circuitry, and a display. The user may return to a previously crimped connection and assess the desirability of the connection by compressing the device about the connection, sending an acoustic signal through the crimp, and comparing the received signal to a signal obtained from known desirable connections.

Device and method for connections made between a crimp connector and wire

A method and apparatus for testing a material such as the water-wall tubes in boilers includes the use of a portable thermal line heater having radiation shields to control the amount of thermal radiation that reaches a thermal imager. A procedure corrects for variations in the initial temperature of the material being inspected. A method of calibrating the testing device to determine an equation relating thickness of the material to temperatures created by the thermal line heater uses empirical data derived from tests performed on test specimens for each material type, geometry, density, specific heat, speed at which the line heater is moved across the material and heat intensity.

Method and apparatus for the portable identification of material thickness and defects along uneven surfaces using spatially controlled heat application

A method is provided for marking electrical wiring with condition indicators. One or more markers are added to one or both of the insulative material and a surface of an electrical conductor such that it bonds thereto. Each marker is capable of emanating into a surrounding atmospheric environment as a gaseous effluent in response to a specific condition experienced by the electrical conductor.

Marking electrical wiring with condition indicators

Passive and active methods for anticipating problems with electrical wiring are provided. An insulative material in contact with an electrical conductor has at least one impurity that is impregnated in the insulative material and/or disposed thereon. An environment around the electrical conductor is monitored for the presence or the level of the impurity(ies) emanating from the insulative material in the form of a gaseous effluent. An alarm signal is generated when a predetermined level of the gaseous effluent is detected.

Method for anticipating problems with electrical wiring

A method and a portable apparatus for the nondestructive identification of defects in structures. The apparatus comprises a heat source (20) and a thermal imager (30) that move at a constant speed past a test surface (10) of a structure. The thermal imager (30) is off set at a predetermined distance from the heat source (10). The heat source (10) induces a constant surface temperature. The imager (20) follows the heat source (10) and produces a video image of the thermal characteristics of the test surface. Material defects produce deviations from the constant surface temperature that move at the inverse of the constant speed. Thermal noise produces deviations that move at random speed. Computer averaging of the digitized thermal image data with respect to the constant speed minimizes noise and improves the signal of valid defects. The motion of thermographic equipment coupled with the high signal to noise ratio render it suitable for portable, on site analysis.

Method and apparatus for the portable identification of material

A heat source such as a magnetic induction/eddy current generator remotely heats a region of a surface of a test structure to a desired depth. For example, the frequency of the heating source can be varied to heat to the desired depth. A thermal sensor senses temperature changes in the heated region as a function of time. A computer compares these sensed temperature changes with calibration standards of a similar sample having known disbond and/or inclusion geography(ies) to analyze the test structure. A plurality of sensors can be arranged linearly to sense vector heat flow.

Growing community of inventors

Yorktown, VA, United States of America

K Elliott Cramer