SEARCH · Engineering Papers

Results for “Transducers”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6

All sources NASA NTRS DOE OSTI

DOE OSTI2024

Development of electro-optical quantum transducers based on three-dimensional superconducting cavities

Quantum transducers enable the conversion of quantum information and signals between different physical platforms. Based on the pioneering works in three-dimensional superconducting cavity technology developed at Fermilab, we are advancing the development of three-dimensional microwave-optical transducers and exploring their applications in quantum information processing and sensing. We present our progress in the design, fabrication, and characterization of three-dimensional microwave cavities integrated with bulk lithium niobate resonators. The material characterization using three-dimensional cavities based on a resonant-type method allows for understanding of complex permittivity and loss mechanism of electro-optic materials at cryogenic temperatures. We also evaluate the potential of the high-efficiency quantum transducers in enhancing the performance of quantum sensors for applications such as dark matter detection, compared to conventional homodyne detection approaches. This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC0207CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics. This work is funded by the DOE's Early Career Research Program. This research used resources of the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Superconducting Quantum Materials and Systems Center (SQMS) under Contract No. DE-AC02-07CH11359.

Zorzetti, Silvia↗

NASA NTRS1969

Cryogenic pressure transducer

Cryogenic pressure transducer utilizes a diaphragm which is electron beam welded to a fitting. This assembly is then heliarc welded to the main body of the transducer. The transducer requires no damping oil and thus is capable of operating at both cryogenic and high temperatures.

Hendrix, J. M.↗

NASA NTRS1972

Transducer applications, a compilation

The characteristics and applications of transducers are discussed. Subjects presented are: (1) thermal measurements, (2) liquid level and fluid flow measurements, (3) pressure transducers, (4) stress-strain measurements, (5) acceleration and velocity measurements, (6) displacement and angular rotation, and (7) transducer test and calibration methods.

Source record↗

NASA NTRS1972

Development of piezoelectric skin friction force vector transducer for a hypersonic wind tunnel

A surface shear force transducer for use in impulse type hypersonic tunnels is described. Sensors are constructed of lead zirconate titanate composition piezoelectric ceramic materials. The diameter of the sensing diaphragm is 0.75 inches and overall transducer dimensions are 1.0 inch diameter and 0.625 inch height. Analysis of the tranducer is made to help design criteria and fabrication techniques. Discussions on design and fabrication techniques are presented as well as performance of transducers delivered.

Kahng, S. K.↗

NASA NTRS1972

A proposed magnetic digital temperature transducer, volume 1

A study has been made of the feasibility of using the discontinuous permeability versus temperature characteristics of some magnetic materials for a digital temperature transducer and a thermally controlled ON-OFF switch. Simple logic converts the number of output pulse to a digital word recognizable by the system. Efforts have been concentrated on materials with Curie temperatures between 0 and 100 C. One compound has the composition Mn(5-x)Fe(x)Ge3 where the amount of iron determines the transition temperature. The other compound is Ni-Zn ferrite and has the compositon Ni(1-x)Zn(x)Fe(1.95)O4 where the nickel: zinc ratio determines the transition temperature. A detailed report of materials prepared is presented. Toroidal inductors of the material have been constructed and the change in inductance with temperature measured. In view of these initial measurements, it is felt that a transducer utilizing the permeability versus temperature characteristics of these materials has promise as a reliable and sensitive solid state digital temperature transducer.

Collier, T. E.↗

NASA NTRS1973

Acoustical transducer calibrating system and apparatus

An acoustical transducer calibrating system includes a differential pressure actuating device having an inner chamber for applying differential pressures to the transducer, and an outer chamber for vacuum sealing. Mounted within the inner chamber is an electrostatic actuator for exciting the transducer at selected frequencies so that its sensitivity can be determined for different operating ambient pressures.

Lewis, T. L.↗

NASA NTRS1974

Contributions to the study of inductive transducers for measuring the amplitude of vibrations in solid media

The design and construction of inductive transducers for measuring the vibrations in metal bars at ultrasonic frequencies are discussed. Illustrations of the inductive transducers are provided. The quantitative relations that are useful in designing the transducers are analyzed. Mathematical models are developed to substantiate the theoretical considerations. Results obtained with laboratory equipment in testing specified metal samples are included.

Dragan, O.↗

NASA NTRS1974

Transducers

The use of transducers in the measuring channels of flight test instrumentation systems is discussed. Emphasis is placed on transducers with an electrical output. The physical effects used for producing the electrical outputs are defined. Diagrams of the various types of transducers are included to show the operating principles.

Weirather, L. H.↗

NASA NTRS1974

Arterial pulse wave pressure transducer

An arterial pulse wave pressure transducer is introduced. The transducer is comprised of a fluid filled cavity having a flexible membrane disposed over the cavity and adapted to be placed on the skin over an artery. An arterial pulse wave creates pressure pulses in the fluid which are transduced, by a pressure sensitive transistor in direct contact with the fluid, into an electric signal. The electrical signal is representative of the pulse waves and can be recorded so as to monitor changes in the elasticity of the arterial walls.

Kim, C.↗

NASA NTRS1974

A follow-on study for miniature solid-state pressure transducer

The activities of a developmental program to design, fabricate and test an absolute pressure transducer based upon the piezojunction properties of silicon are summarized. The prime problem addressed is the development of a housing capable of applying the high stress levels needed for sensitive piezojunction operation but at the same, free from the creep effects and the fragility that limit the usefulness of previous designs. The first part of the report describes the initial fabrication and test and reviews the theory of sensor performance. The second part incorporates two recommendations of the first part (the use of commercially manufactured silicon planar mesa diodes and the adoption of an all-silicon structure for loading) and presents some preliminary test data on the transducers thus fabricated. These initial measurements show much improved performance over any previously fabricated piezojunction transducers but testing is incomplete and several problems in manufacturing technology remain.

Source record↗

NASA NTRS1975

Fluctuating surface pressure measurements on USB wing using two types of transducers

Measurements of the fluctuating pressures on the wing surface of an upper-surface-blown powered-lift model and a JT15 engine were obtained using two types of pressure transducers. The pressures were measured using overall-fluctuating pressures and power spectral density analyses for various thrust settings and two jet impingement angles. Comparison of the data from the two transducers indicate that similar results are obtained in the lower frequency ranges for both transducers. The data also indicate that for this configuration, the highest pressure levels occur at frequencies below 2000 Hz.

Reed, J. B.↗

NASA NTRS1976

A dynamic pressure source for the calibration of pressure transducers

A dynamic pressure source is described for producing sinusoidally varying pressures of up to 34 kPa zero to peak, over the frequency range of approximately 50 Hz to 2 kHz. The source is intended for the dynamic calibration of pressure transducers. The transducer to be calibrated is mounted near the base of the thick walled aluminum tube forming the vessel so that the pressure sensitive element is in contact with the liquid in the tube. A section of the tube is filled with small steel balls to damp the motion of the 10-St dimethyl siloxane working fluid in order to extend the useful frquency range to higher frequencies than would be provided by an undamped system. The dynamic response of six transducers provided by the sponsor was evaluated using the pressure sources; the results of these calibrations are given.

Vezzetti, C. F.↗

NASA NTRS1978

Low-cost ultrasonic lamb-wave transducer

Transducer propagates Lamb wave through thin aluminum sheet material. Model includes two elements that measure effects of damping and loading which, in turn, are indirectly equated to bond integrity. Transducer has been used to evaluate bond integrity of aluminum facing adhesively bonded to aluminum facing. Because of versatility, it is now possible to inspect many objects of different configurations that could not be reached with earlier transducers.

Kammerer, C. C.↗

NASA NTRS1978

Magnetometer with a miniature transducer and automatic scanning

The magnetometer is based on the time variation of the magnetic permeability in the magnetic material of its transducer; however, its operation is substantially different from the ordinary flux-gate magnetometer. The transducer uses 0.05 mm diameter plated magnetic wire and is made flat enabling it to make measurements of transverse magnetic fields as close as 0.08 mm from the surface, and it has very good spatial resolution because of its small active region of approximately 0.64 mm by 0.76 mm. The magnetometer uses an inexpensive clip-on millimeter for driving and processing the electrical signals and readout. It also utilizes an automatic scanning technique which is made possible by a specially designed transducer holding mechanism that replaces the ink pen on an X-Y recorder.

Debnam, W. J. J.↗

NASA NTRS1980

Crack-opening displacement transducer

Crack-opening displacement transducer consists of 30 deg cone, coil spring, and linear-displacement transducer. Conical probe is used to measure crack opening. Cone is pressed firmly into crack by spring. As applied load causes crack to open up, cone is pushed further into it. Movement of cone, and thus crack growth, is monitored by linear-displacement transducer. Method gives more accurate measurement of crack-opening displacement of very narrow slots.

Simonds, R. A.↗

NASA NTRS1981

Transducer for extreme temperatures and pressures

Transducer with limits of 500 C and 10 kilobars responds to mechanical vibrations up to 20 kHz. Vibration pickup performs well in nuclear reactors, turbines, and other extreme environments. Low pressure problems of outgassing and "virtual" leakage experienced with conventional transducers potted in epoxy are eliminated with use of glass and metal supports. Interior opens to atmosphere, preventing buildup of pressure-induced stresses. Spring holds transducer against housing, reducing strain distortion.

Nadler, H.↗

NASA NTRS1980

Simulation of transducer-couplant effects on broadband ultrasonic signals

The increasing use of broadband, pulse-echo ultrasonics in nondestructive evaluation of flaws and material properties has generated a need for improved understanding of the way signals are modified by coupled and bonded thin-layer interfaces associated with transducers. This understanding is most important when using frequency spectrum analyses for characterizing material properties. In this type of application, signals emanating from material specimens can be strongly influenced by couplant and bond-layers in the acoustic path. Computer synthesized waveforms were used to simulate a range of interface conditions encountered in ultrasonic transducer systems operating in the 20 to 80 MHz regime. The adverse effects of thin-layer multiple reflections associated with various acoustic impedance conditions are demonstrated. The information presented is relevant to ultrasonic transducer design, specimen preparation, and couplant selection.

Vary, A.↗

NASA NTRS1980

Simultaneous muscle force and displacement transducer

A myocardial transducer for simultaneously measuring force and displacement within a very small area of myocardium is disclosed. The transducer comprised of an elongated body forked at one end to form an inverted Y shaped beam with each branch of the beam constituting a low compliant tine for penetrating the myocardium to a predetermined depth. Bonded to one of the low compliance tines is a small piezoresistive element for converting a force acting on the beam into an electrical signal. A third high compliant tine of the transducer, which measures displacement of the myocardium in a direction in line with the two low compliant tines, is of a length that just pierces the surface membrane. A small piezoresistive element is bonded to the third tine at its upper end where its bending is greatest. Displacement of the myocardium causes a deformation in curvature of the third tine, and the second small piezoresistive element bonded to the surface of its curved end converts its deformation into an electrical signal.

Feldstein, C.↗