Abstract: A measurement system employs a method and apparatus for uniquely tagging each of a plurality of transducers, automatically recognizing the tag for identifying the transducer and automatically adjusting electronic parameters of the system for enhancing performance with a selected transducer. In a preferred embodiment, a resistor is inserted in a piezoelectric transducer of an ultrasonic thickness gauge, a current source and A to D converter measure the resistor and a microprocessor-based logic system adjusts measurement parameters of the gauge to be automatically optimized for the associated transducer characteristics.

Abstract: A microprocessor-controlled, hand-held, digital ultrasonic thickness gage having automatic zero calibration, scroll velocity adjustment and an electronic locking feature to prevent inadvertent calibration or velocity data variations. This invention is used with a dual-element transducer and, in that regard, employs a microprocessor program which automatically corrects for the well-known, inherent thickness gaging inaccuracies (nonlinearities) always caused by the use of the otherwise advantageous (high sensitivity) dual element transducer.

Abstract: A bolt elongation measurement apparatus and method for measuring the length of bolts of all sizes and shapes. The apparatus utilizes a microprocessor-based digital system including a binary counter which counts pulses generated by a high frequency oscillator during the time interval between the entry into the bolt of a first pulse and exit from the bolt of a second pulse derived from the reflection return of ultrasonic energy from the opposite end of the bolt. The count is applied to a computer for calculation of bolt length or of bolt stretch due to mechanical stress. The calculation also incorporates data input via thumbwheel switches and corresponding to material velocity, stress correction factor, measurement temperature, and thermal correction factor. A unique digital filtering algorithm ensures an accurate and stable measurement.

Abstract: A non-destructive bond testing apparatus utilizes impedance variation represented by both the phase and amplitude of the signal vector response of a sonic energy generating and receiving probe, which is applied to a laminar, honeycomb or fiber composite structure under test. Typical bonding methods for which this bondtester and method are applicable include adhesive bonding, diffusion bonding, brazing, resistance and impact/friction bonding. A cathode ray tube displays the tip of the vector (as a bright dot) which represents the impedance characteristic affected by the structure under test.