Improvement of Linear Displacement of an Inchworm

2017 ◽  
Vol 137 (12) ◽  
pp. 1600-1606
Author(s):  
Akihiro Torii ◽  
Yuta Mitsuyoshi ◽  
Suguru Mototani ◽  
Kae Doki
Keyword(s):  
Linear Displacement

Modelling Light Transmission in a Fiber-Optical Reflection System

2004 ◽  
Vol 9 (1) ◽  
pp. 55-63
Author(s):  
V. Kleiza
Keyword(s):  
Optical Sensors ◽  
Light Transmission ◽  
External Cavity ◽  
Linear Displacement ◽  
Fiber System ◽  
Light Emitting ◽  
Optical Media ◽  
Reflected Light ◽  
Fiber Optical ◽  
Fiber Optical Sensors

Light transmission in the reflection fiber system, located in external optical media, has been investigated for application as sensors. The system was simulated by different models, including external cavity parameters such as the distance between light emitting and receiving fibers and mirror positioning distance. The sensitivity to a linear displacement of the sensors was studied as a function of the distance between the tips of the light emitting fiber and the center of the pair reflected light collecting fibers, by positioning a mirror. Physical fundamentals and operating principles of the advanced fiber optical sensors were revealed.

scholarly journals Displacement Estimation Based on Optical and Inertial Sensor Fusion

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1390
Author(s):  
Tomasz Ursel ◽  
Michał Olinski
Keyword(s):  
Sensor Fusion ◽  
Inertial Sensor ◽  
External Disturbance ◽  
Linear Displacement ◽  
Measuring System ◽  
Displacement Estimation ◽  
Mems Accelerometer ◽  
Pedestrian Navigation ◽  
Complementary Filter ◽  
Optical Flow Sensor

This article aims to develop a system capable of estimating the displacement of a moving object with the usage of a relatively cheap and easy to apply sensors. There is a growing need for such systems, not only for robots, but also, for instance, pedestrian navigation. In this paper, the theory for this idea, including data postprocessing algorithms for a MEMS accelerometer and an optical flow sensor (OFS), as well as the developed complementary filter applied for sensor fusion, are presented. In addition, a vital part of the accelerometer’s algorithm, the zero velocity states detection, is implemented. It is based on analysis of the acceleration’s signal and further application of acceleration symmetrization, greatly improving the obtained displacement. A test stand with a linear guide and motor enabling imposing a specified linear motion is built. The results of both sensors’ testing suggest that the displacement estimated by each of them is highly correct. Fusion of the sensors’ data gives even better outcomes, especially in cases with external disturbance of OFS. The comparative evaluation of estimated linear displacements, in each case related to encoder data, confirms the algorithms’ operation correctness and proves the chosen sensors’ usefulness in the development of a linear displacement measuring system.

An enlarge polymer optical fiber linear-displacement sensor based on constructive interference

2021 ◽  
Vol 63 ◽  
pp. 102481
Author(s):  
Abdul Ghaffar ◽  
Mujahid Mehdi ◽  
YanYun Hu ◽  
Arnaldo G. Leal-Junior ◽  
Abdul Basit ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Linear Displacement ◽  
Displacement Sensor ◽  
Polymer Optical Fiber ◽  
Constructive Interference

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

Оdrеđivаnjе brzinе struјаnjа vаzduhа u prаvоugаоnоm zаtvоrеnоm cevovodu korišćenjem metoda polja brzina

2021 ◽  
Vol 23 (2) ◽  
pp. 57-63
Author(s):  
Marija Lazarevikj ◽  
◽  
Valentino Stojkovski ◽  
Viktor Iliev
Keyword(s):  
Velocity Profile ◽  
Flow Rate ◽  
Air Flow ◽  
Displacement Transducer ◽  
Linear Displacement ◽  
Local Velocity ◽  
Air Flow Rate ◽  
Mean Velocity ◽  
Measured Velocity ◽  
Integration Techniques

In the technical practice, it is often necessary to measure or control the fluid flow rate in pipelines and channels. The velocity-area method requires a number of meters located at specified points in a suitable cross-section of closed conduits. Simultaneous measurements of local mean velocity with the meters are integrated over the gauging section to provide the discharge. In this paper, three approaches of this method are applied on a rectangular closed conduit to determine the air flow rate with integration techniques used to compute the discharge assume velocity distributions that closely approximate known laws, especially in the neighborhood of solid boundaries. For this purpose, meters for velocity were 7 Pitot tubes placed vertically in predefined measurement points covering the conduit height, and moved horizontally along the conduit width. The position of the Pitot tubes along the conduit width was monitored and controlled by a linear displacement transducer. Pressure is measured using digital sensors. The first technique for determination of air flow rate is on basis of fixed (stopping) measuring points across the conduit width as averaged values of local velocity, the second one is semi continual measurement of velocity profile by applying interpolation between the average local velocity on fixed (stopping) points and measured velocity in the movement between two positions, and the third is by continuously moving the Pitot tubes without stopping. The results of the three techniques are calculated and presented using different types of software. Considering the last technique, comparison of results is made applying different movement speeds of the Pitot tubes in order to examine their influence on the velocity profile.

Dilator actions of arginine in human peripheral vasculature

1991 ◽  
Vol 81 (5) ◽  
pp. 695-700 ◽  
Author(s):  
Alison Calver ◽  
Joe Collier ◽  
Patrick Vallance
Keyword(s):  
Nitric Oxide ◽  
Blood Flow ◽  
Forearm Blood Flow ◽  
Hypotensive Effect ◽  
Linear Displacement ◽  
High Dose ◽  
Free Base ◽  
Peripheral Vasculature ◽  
Arginine Hydrochloride

1. l-Arginine is the physiological precursor for the formation of endothelium-derived nitric oxide. The synthesis of nitric oxide is stereospecific: d-arginine is not a substrate for nitric oxide synthase. It is possible that the provision of excess l-arginine substrate might increase the vascular synthesis of nitric oxide. We have examined this possibility by studying the effects of local infusion of l-and d-arginine in the forearm resistance bed and the superficial dorsal hand veins of healthy subjects. 2. Drugs were either infused locally into a vein on the back of the hand and then the vein diameter was measured using a linear displacement technique, or into the brachial artery and then the forearm blood flow was measured by venous occlusion plethysmography. 3. In the superficial hand veins, l- and d-arginine free base and l- and d-arginine hydrochloride (all four preparations at a dose of 5 μmol/min) all caused a significant increase in venous diameter. The responses of the l-and d-enantiomers did not differ significantly from one another. 4. In the forearm resistance bed, l- and d-arginine free base and l-arginine hydrochloride were without effect at doses of 10 and 40 μmol/min. However, at doses of 160 μmol/min all three preparations of arginine caused a significant increase in forearm blood flow compared with control values. The responses to the three preparations of arginine did not differ significantly from one another. 5. These results show that arginine in high dose is a vasodilator in both human resistance vessels and superficial veins in vivo. The response to arginine was not stereospecific: both the l- and d-enantiomers had the same effect. The dilator effect of high-dose arginine showed neither arterio-nor veno-selectivity. 6. This suggests that the hypotensive effect of systemic infusions of l-arginine in man is mediated by peripheral vasodilatation. It is not possible to ascribe the actions of arginine supplementation in this study to activation of the l-arginine/nitric oxide pathway through the provision of excess substrate.

Design, Analysis and System-Level Modelling of a Single Axis Capacitive Accelerometer

2016 ◽  
Author(s):  
Zakriya Mohammed ◽  
Owais Talaat Waheed ◽  
Ibrahim (Abe) M. Elfadel ◽  
Aveek Chatterjee ◽  
Mahmoud Rasras
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Noise Analysis ◽  
Linear Displacement ◽  
Operating Conditions ◽  
System Level ◽  
Complete Analysis ◽  
Capacitive Accelerometer ◽  
Static Capacitance ◽  
Cross Axis

The paper demonstrates the design and complete analysis of 1-axis MEMS capacitive accelerometer. The design is optimized for high linearity, high sensitivity, and low cross-axis sensitivity. The noise analysis is done to assure satisfactory performance under operating conditions. This includes the mechanical noise of accelerometer, noise due to interface electronics and noise caused by radiation. The latter noise will arise when such accelerometer is deployed in radioactive (e.g., nuclear power plants) or space environments. The static capacitance is calculated to be 4.58 pF/side. A linear displacement sensitivity of 0.012μm/g (g = 9.8m/s2) is observed in the range of ±15g. The differential capacitive sensitivity of the device is 90fF/g. Furthermore, a low cross-axis sensitivity of 0.024fF/g is computed. The effect of radiation is mathematically modelled and possibility of using these devices in radioactive environment is explored. The simulated noise floor of the device with electronic circuit is 0.165mg/Hz1/2.

Motion Trajectory Simulation and Measurement of the 5000V Electromagnetic Repulsion Mechanism (ERM)

2012 ◽  
Vol 546-547 ◽  
pp. 368-373
Author(s):  
Jin Wu ◽  
Jin Wu Zhuang ◽  
Yong Hua Zhuang ◽  
Jun Lu
Keyword(s):  
Comparative Analysis ◽  
Simulation Models ◽  
Displacement Transducer ◽  
Linear Displacement ◽  
The Other ◽  
Displacement Sensor ◽  
Motion Trajectory ◽  
Motion Trajectories ◽  
Trajectory Simulation ◽  
Piezoelectric Acceleration

Successful applications of the ERM depend on accurate simulation models. Firstly, we built up a model on the 5000 volts ERM with ansoft. Then we measured motion trajectories of the ERM prototype respectively by means of a piezoelectric acceleration transducer, a magnetic grating displacement transducer and a linear displacement sensor. Based on the comparative analysis of the results from simulation and measurement, we concluded that the simulation model was reliable on one hand, and on the other hand by means of a linear displacement sensor along with a magnetic grating counterpart, we could obtain accurate motion trajectories with a relative error less than 5%.

scholarly journals High precision machining of a displacement sensor for helicoidal motions

2021 ◽  
Author(s):  
Zeina ELRAWASHDEH ◽  
Philippe REVEL ◽  
Christine PRELLE ◽  
Frédéric LAMARQUE
Keyword(s):  
High Precision ◽  
Fiber Optic ◽  
Geometric Model ◽  
Translational Motion ◽  
Surface Characteristics ◽  
Measurement Range ◽  
Linear Displacement ◽  
Displacement Sensor ◽  
Fiber Optic Probes

Abstract This research study presents the design and the high precision manufacture procedure of a fiber-optic displacement sensor. It is composed of two fiber-optic probes associated with a structure of a cones’ grating. The sensor is characterized by its ability to measure the linear displacement for an axis performing a helicoidal motion. This motion has been demonstrated on a high precision lathe; where the spindle provided the rotational motion, associated to a translational motion on the linear stage. This allowed to obtain the two simultaneous motions. The displacement of the translational stage is measured by the sensor in real time.Firstly, a highly precise geometric model of the reflector part for the sensor was developed. This model provided a specific geometry for the cones-assembled grating, which has been precisely manufactured. The geometric parameters and the surface characteristics of each step in the fabricated grating were both identified in situ on the lathe. The agreement between simulation and experimental results is excellent. The performances of the fiber-optic displacement sensor were identified in-situ on the lathe. The analysis of the voltage output signals from the two fiber-optic probes is used to measure the grating displacement. The unbalanced rotation due to non-centered axes was also characterized. The sensor provided a micrometric resolution, on a measurement range of more than one centimeter.

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