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Microelectromechanical systems production is still an immature technology compared to the classical semiconductor industry. MEMS fabrication and packaging processes may present misalignments which result in an improper placement of the internal microstructures or dies. In this work, the possibilities of diagnosing mechanical misalignments of dual axis IC accelerometers are explored. The used method dynamically correlates the two output signals in orthogonal directions. This leads to a Lissajous composition which is able to manifest the actual level of misalignment. The definition of a metric and its variation rate study allows the diagnosis procedure. Experimental results using a commercial dual axis capacitive accelerometer reveal diagnosis discrepancies as low as 1.1%, therefore showing the viability of the proposal., Postprint (published version)

Postprint (published version)

Postprint (published version)

The purpose of this investigation is to evaluate the earthquake hazards at Eisenhower and Snell Locks along the Saint Lawrence Seaway and to provide time histories for earthquake ground motion that represent the cyclic shaking that would be felt in the free field on bedrock at the lock sites. Ground motions defined by this study are for use in the engineering-seismic evaluation of the respective locks. This study consists of both a geological and a seismological analysis and consists of the following (1) a geological evaluation of fault activity at the sites and in the region, (2) a seismological appraisal of the historic seismicity in the region, (3) as interpretation of seismic source areas and maximum earthquakes with their prospects for recurrence, and (4) attenuated peak ground motions at the sites with time histories aor analogous cyclic shaking. The area covered by this study are the sites of the Eisenhower and Snell locks near Massena, New York, portions of New England and Canada and the St. Lawrence Valley which has been a source of major historic earthquakes.

Contents: Test Site Layout; Coordinate Systems; Instrumentation; Channel Record Assignments; Measurement Identification; Transducers; Canister Placement in Slant Hole; Free Field Blast Pressure Gage Installations; and Connection Diagrams., See also Volume 1, AD-B013 123L.

Many Air Force Air-launched guided weapons require that the Inertial Reference Platform (IRP) be air aligned prior to launch. This generally means that alignment data must be transferred from the carrier IRP. Accuracy limitations are encountered due to aircraft structural flexure, gust-induced noise, and an accuracy mismatch between the two platforms. An experimental program was carried out to determine how accurately an alignment could be performed between a master navigator and a developmental weapon IRP. The tests were made between the two IRP's to simulate air-to-air alignment and also to attain an understanding of the alignment problem when simulated flexure motion was imparted to the developmental IRP. (Author)

A requirement exists for a low-cost, midcourse inertial guidance system for application in air-to-surface tactical missiles. A unique, low-cost, gimballed inertial guidance platform intended to satisfy objectives for such a system has been developed. The approach pursued was to develop new techniques and low-cost hardware directly for these medium accuracy applications, considering from the start techniques that readily adapt to mass production. The effort covered by this report concerns the fabrication and test of a prototype version of the low-cost platform. (Author)

Describes research results in orbital tests of instruments, instrument development, and guidance and control techniques, specifically: (a) Development of experiments testing special inertial instruments in a Drag-Free Satellite: The unsupported gyroscope. (b) Orbital tests of existing instruments. (c) He3 nuclear gyro development. (d) Optimal guidance concepts. (e) Theory of stochastic control. (f) Tropospheric propagation aspects of radio guidance. (g) Laser applications to aerospace guidance. (h) Ring laser project. (j) Fluidics. (Author)

The Missile Impact Predictor System is installed on the missile to provide the down-range ground equipment with a means of predicting the impact point of the missile from the instantaneous position of the missile in its flight path. The Impact Predictor Monitor Set tests the Missile Impact Predictor System on the ground by simulating the signals that would be transmitted by the ground station during missile flight and monitoring the responses of each of the three missile components. The Monitor Set applies the proper r-f signals at various power levels and frequencies and monitors the power and frequency responses of the missile components. (Author)

A description is given of the Wing VI Minuteman Transportation and Handling program vibration surveys and endurance testing of Second-Stage Motor 52TH-4. Wing VI Second-Stage Minuteman Motor 52TH-4 was subjected to controlled sinusoidal vibration tests conducted in three phases. The Phase I tests consisted of longitudinal axis vibration surveys at frequencies between 10 and 300 cps at nominal excitation amplitudes of 0.5 and 1.0 g. The Phase II tests were transverse axis symmetric and anti-symmetric vibration surveys over the same frequency band and at the same input levels as the Phase I tests. The final test, Phase III, was a 10.5-hr endurance test conducted at a frequency of 20 cps and excitation amplitudes of 1.5, 2.0, 2.5, and 3.0 g. Radiographic and visual examinations of the motor and the LITVC and RC system after the surveys and endurance test revealed no structural damage; the motor was successfully static fired at sea-level conditions.

This guide presents the necessary information required to make machinery noise measurements with a high degree of confidence. Airborne noise measurements will not be included, since information concerning these measurements is voluminous and may be found in many publications. Structureborne (solidborne) noise measurements will be the prime interest, and the best state of the art techniques of measurement and analysis will be directed toward the technician and engineer. (Author)

This paper comprises a description of test equipment with the aid of which vibrations having a frequency range from 30 to 1000c/sec, and with amplitudes up to 2mm can be transmitted to a human body. Reasons are given for the designs selected and construction difficulties are pointed out. The different oscillators are enumerated and their mode of operation is explained. (Author), Trans. of article from an unidentified source, n.d.

Results of continuous setback shock and pressure measurements made in a shortened 5 in/54 gun are presented, and the test apparatus, hardwire instrumentation and data analysis equipment are described. Single and multiple copper-ball accelerometer measurements of setback and other shocks in several 5 in/54 guns are discussed, and two artillery projectile copper-ball accelerometers are described. Response spectra computed and extrapolated from the recorded shock transients show the effect of setback shock on simple structures and assess the validity of the copper-ball accelerometer measurements. Both recording systems yielded useful information on the overall characteristics of artillery projectile shock. (Author)