Dynamics of jet displacement transducers with a relay calibration characteristic

1979 ◽  
Vol 22 (4) ◽  
pp. 412-414
Author(s):  
V. A. Samodurov
Keyword(s):  
Calibration Characteristic ◽  
Displacement Transducers

Linear-displacement transducers for surface acoustic waves

1985 ◽  
Vol 28 (1) ◽  
pp. 31-33 ◽  
Author(s):  
V. Yu. Snitko ◽  
V. I. Mizarene ◽  
K. M. Ragul'skis
Keyword(s):  
Acoustic Waves ◽  
Surface Acoustic Waves ◽  
Linear Displacement ◽  
Displacement Transducers

Load Monitoring of Aerospace Structures Using Micro-Electro-Mechanical Systems (MEMS)

2012 ◽  
Author(s):  
M. Martinez ◽  
B. Rocha ◽  
M. Li ◽  
G. Shi ◽  
A. Beltempo ◽  
...  
Keyword(s):  
Least Squares ◽  
Mechanical Systems ◽  
National Research Council ◽  
Micro Electro Mechanical Systems ◽  
Displacement Estimation ◽  
Polynomial Fit ◽  
Load Monitoring ◽  
Variable Displacement ◽  
Displacement Transducers ◽  
Spatial Locations

The National Research Council of Canada has developed Structural Health Monitoring (SHM) test platforms for load and damage monitoring, sensor system testing and validation. One of the SHM platform consists of two 2.25 meter long, simple cantilever aluminium beams that provide a perfect scenario for evaluating the capability of a load monitoring system to measure bending, torsion and shear loads. In addition to static and quasi-static loading procedures, these structures can be fatigue loaded using a realistic aircraft usage spectrum while SHM and load monitoring systems are assessed for their performance and accuracy. In this study, Micro-Electro-Mechanical Systems (MEMS), consisting of triads of gyroscopes, accelerometers and magnetometers, were used to compute changes in angles at discrete stations along the structure. A Least Squares based algorithm was developed for polynomial fitting of the different data obtained from the MEMS installed in several spatial locations of the structure. The angles obtained from the MEMS sensors were fitted with a second, third and/or fourth order degree polynomial surface, enabling the calculation of displacements at every point. The use of a novel Kalman filter architecture was evaluated for an accurate angle and subsequent displacement estimation. The outputs of the newly developed algorithms were then compared to the displacements obtained from the Linear Variable Displacement Transducers (LVDT) connected to the structures. The determination of the best Least Squares based polynomial fit order enabled the application of derivative operators with enough accuracy to permit the calculation of strains along the structure. The calculated strain values were subsequently compared to the measurements obtained from reference strain gauges installed at different locations on the structure. This new approach for load monitoring was able to provide accurate estimates of applied strains and loads.

scholarly journals Stability and Resolution of Three Types of Commercially Available Displacement Transducers

1991 ◽  
Vol 44 (4) ◽  
pp. 365-367
Author(s):  
Hideki KAWADA ◽  
Osamu OKITSU ◽  
Hideo TSUNAKAWA ◽  
Toshi ASADA
Keyword(s):  
Displacement Transducers

CCD Camera Calibration Technology Based on the Translation of Coordinate Measuring Machine

2014 ◽  
Vol 568-570 ◽  
pp. 320-325 ◽  
Author(s):  
Feng Shan Huang ◽  
Li Chen
Keyword(s):  
Coordinate System ◽  
Camera Calibration ◽  
Characteristic Point ◽  
Coordinate Measuring Machine ◽  
Ccd Camera ◽  
Mathematic Model ◽  
Calibration Method ◽  
Calibration Characteristic ◽  
Standard Sphere ◽  
Measuring Machine

A new CCD camera calibration method based on the translation of Coordinate Measuring Machine (CMM) is proposed. The CMM brings the CCD camera to produce the relative translation with respect to the center of the white ceramic standard sphere along the X, Y, Z axis, and the coordinates of the different positions of the calibration characteristic point in the probe coordinate system can be generated. Meanwhile, the camera captures the image of the white ceramic standard sphere at every position, and the coordinates of the calibration characteristic point in the computer frame coordinate system can be registered. The calibration mathematic model was established, and the calibration steps were given and the calibration system was set up. The comparing calibration result shows that precision of this method is equivalent to that of the special calibration method, and the difference between the calibrating data of these two methods is within ±1μm.

Self-monitoring Properties of Concrete Columns with Embedded Cement-based Strain Sensors

2011 ◽  
Vol 22 (2) ◽  
pp. 191-200 ◽  
Author(s):  
Huigang Xiao ◽  
Hui Li ◽  
Jinping Ou
Keyword(s):  
Cyclic Load ◽  
Failure Modes ◽  
Concrete Structures ◽  
Concrete Columns ◽  
Strain Sensors ◽  
Strain Sensing ◽  
Self Monitoring ◽  
Good Strain ◽  
Displacement Transducers ◽  
Monotonic Load

Cement-based strain sensors (CBCC sensor) were fabricated by taking the advantage of piezoresistivity of CB-filled CBCC. CBCC sensors were centrally embedded into concrete columns (made with C40 and C80 concretes, respectively) to monitor the strain of the columns under cyclic load and monotonic load by measuring the resistance of CBCC sensors. The comparison between the monitored results of CBCC sensors and that of traditional displacement transducers indicates that CBCC sensors have good strain-sensing abilities. Meanwhile, CBCC sensors exhibit different failure modes that break later than C40 concrete columns, but a little earlier than C80 concrete columns. Therefore, the strength-matching principle between embedded CBCC sensors and concrete columns is proposed in this article to guarantee the sensing capacity of CBCC sensors in various concrete structures. The analytical results agree well with the experimental phenomena.

Micromachined tunneling displacement transducers for physical sensors

1993 ◽  
Vol 11 (4) ◽  
pp. 797-802 ◽  
Author(s):  
T. W. Kenny ◽  
W. J. Kaiser ◽  
J. A. Podosek ◽  
H. K. Rockstad ◽  
J. K. Reynolds ◽  
...  
Keyword(s):  
Physical Sensors ◽  
Displacement Transducers

High-sensitivity displacement transducers in control and measuring equipment

1980 ◽  
Vol 23 (8) ◽  
pp. 697-702
Author(s):  
V. V. Kozlov ◽  
V. P. Sokolov ◽  
Yu. K. Zavodov
Keyword(s):  
Measuring Equipment ◽  
High Sensitivity ◽  
Displacement Transducers

Age-related changes in gallbladder contractility and cytoplasmic Ca2+ concentration in the guinea pig

1993 ◽  
Vol 264 (4) ◽  
pp. G624-G629 ◽  
Author(s):  
J. Ishizuka ◽  
M. Murakami ◽  
G. A. Nichols ◽  
C. W. Cooper ◽  
G. H. Greeley ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
Contractile Force ◽  
Binding Ability ◽  
Age Related ◽  
Displacement Transducers ◽  
Force Displacement ◽  
Dose Dependent Increase ◽  
Muscle Compliance ◽  
Dose Dependent

Gallbladder (GB) motility diminishes with aging. This study was performed to characterize mechanisms that are involved in changes in GB contractility that occur during aging. Cytoplasmic Ca2+ concentrations ([Ca2+]i) and the contractile force of guinea pig GB muscle strips were simultaneously measured using fura-2 and force-displacement transducers. The binding ability of the Ca2+ channel antagonist and GB muscle compliance were also examined. The COOH-terminal octapeptide of cholecystokinin (CCK-8) evoked a dose-dependent increase in force and [Ca2+]i. Changes of [Ca2+]i and contractile force of muscle strips in response to CCK-8 were significantly greater in young (2 mo old) compared with mature and aged (12 and 24 mo old) guinea pigs (changes in [Ca2+]i, ED50: 46.1 nM at 2 mo, 6.1 microM at 12 mo, and 2.8 mM at 24 mo; changes of contractile force, ED50: 24.8 microM at 2 mo, 2.1 mM at 12 mo, and 357 mM at 24 mo). However, the magnitude of the contraction at each percent change in [Ca2+]i was actually similar in young and aged guinea pigs. In a Ca(2+)-free buffer, the responses of [Ca2+]i and force to CCK-8 in both young and aged GB muscles decreased, but those were still dose and age dependent. Binding ability of the Ca2+ channel antagonist did not differ in the young and aged groups, but the compliance of the GB muscle strip decreased with aging. These results suggest that both a reduced mobilization of intracellular Ca2+ and a decreased muscle compliance are responsible, at least in part, for age-related reduced contraction of guinea pig GB in response to CCK.

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