Abstract: A rotating holder assembly includes a base, a strap assembly, a plate, and an accessory holder. The base defines opposing surfaces, an open-ended tubular portion located between the two surfaces, a cylindrical post coupled to and extending perpendicularly away from one surface, and a cap coupled to the outboard end of the post. The cap defines a substantially hemispherical shape having a diameter that is greater than a diameter of the post. The strap assembly includes a stretchable strap extending through the tubular portion, and a coupler for securing the stretchable strap into a loop of selectable size. The plate has a hole extending therethrough having an axial length that is less than an axial length of the post, and a diameter that is less than the diameter of the cap and greater than the diameter of the post. The accessory holder is coupled to the plate.

Abstract: The present invention is directed to an apparatus and method for a measurement system for the testing of transducers, and more particularly to the testing of piezoelectric transducers. The measurement system includes a transducer, a feedback amplifier coupled to the transducer and a signal processing circuit coupled to the output of the amplifier. The method of testing the transducer includes coupling the test signal to the transducer, disabling the amplifier, and measuring the response of the transducer to the test signal with the test processing circuit.

Abstract: The present invention is directed to an apparatus and method for a measurement system for the testing of transducers, and more particularly to the testing of piezoelectric transducers. The measurement system includes a transducer, a feedback amplifier coupled to the transducer and a signal processing circuit coupled to the output of the amplifier. The method of testing the transducer includes coupling the test signal to the transducer, disabling the amplifier, and measuring the response of the transducer to the test signal with the test processing circuit.

Abstract: An autonomous sensor system is provided for powering sensors using thermoelectric modules driven by thermal energy. The system includes solid-state thermoelectric (TE) modules for the conversion of thermal energy to electrical energy. The TE modules are composed of p-type and n-type semiconductors that are interdigitated so that the p-type and n-type elements form thermocouples. The TE modules derive electrical power from thermal energy available in the immediate environment. The system also includes sensors that are powered by the TE module, wherein a corresponding free space signal is generated.

Abstract: An instrumented test hammer for use in vibrationally exciting a test object includes a head assembly having an impact tip and a transducer operatively arranged to sense the force of an impact between the tip and object and to convert such sensed force into a proportional electrical signal, a handle extending away from the head assembly, and a cushioned grip surrounding a portion of the handle at a location spaced from the head assembly. The hammer is "tuned", by proper selection of the grip material and by selection of the ratio of the total mass of the head assembly to the combined mass of the handle and grip, such that the node of the first translational resonant mode of the hammer, after impacting against an object, is located substantially proximate the head assembly, independently of the manner by which the grip is held. The improved hammer substantially avoids the generation of spurious electrical signals due to post-impact vibration of the head assembly.