A Proportional Piezoelectric Electro-Fluidic Pneumatic Value Design

1981 ◽  
Vol 103 (4) ◽  
pp. 361-365 ◽  
Author(s):  
C. K. Taft ◽  
B. M. Herrick
Keyword(s):  
Mathematical Model ◽  
Input Signal ◽  
Experimental Measurements ◽  
Bender Element ◽  
Pneumatic Valve

The development of a proportional electro-fluidic pneumatic valve is presented. The first stage of the valve consists of a piezoelectric bender element of bimorph construction centered between two nozzles. The bimorph is deformed by an electrical input signal. This, in turn, causes a change in pressure at the output of the nozzles, which will then be amplified to a usable level using cascaded laminar proportional amplifiers. A mathematical model of the valve’s behavior is discussed and verified with experimental measurements.

Pulse-Width Modulated Amplifier for DC Servo System and Its Matlab Simulation

2015 ◽  
Vol 9 (1) ◽  
pp. 625-631
Author(s):  
Ma Xiaocheng ◽  
Zhang Haotian ◽  
Cheng Yiqing ◽  
Zhu Lina ◽  
Wu Dan
Keyword(s):  
Mathematical Model ◽  
Transfer Function ◽  
Input Signal ◽  
Pulse Width ◽  
Rotation Speed ◽  
Servo Motor ◽  
Matlab Simulation ◽  
Pulse Width Modulated ◽  
Signal Changes ◽  
The Relationship

This paper introduces a mathematical model for Pulse-Width Modulated Amplifier for DC Servo Motor. The relationship between pulse-width modulated (PWM) signal and reference rotation speed is specified, and a general model of motor represented by transfer function is also put forward. When the input signal changes, the rotation speed of the servo motor will change accordingly. By changing zeros and poles, transient performance of this system is discussed in detail, and optimal ranges of the parameters is recommended at the end of discussion.

Thickness Deformation of Constrained Layer Damping: An Experimental and Theoretical Evaluation

2000 ◽  
Vol 123 (2) ◽  
pp. 213-221 ◽  
Author(s):  
Peter Y. H. Huang ◽  
Per G. Reinhall ◽  
I. Y. Shen ◽  
Jessica M. Yellin
Keyword(s):  
Mathematical Model ◽  
Transfer Functions ◽  
Viscoelastic Layer ◽  
Experimental Setup ◽  
Experimental Measurements ◽  
Constrained Layer Damping ◽  
Response Functions ◽  
Theoretical Evaluation ◽  
Calculated Frequency ◽  
Direct Measurements

This paper presents a study of thickness deformation of the viscoelastic material in constrained layer damping (CLD) treatments. The first goal of the study is to demonstrate the feasibility of using direct measurement to investigate thickness deformation in CLD treatments. The experimental setup consisted of a constrained layer beam cantilevered to a shaker, an accelerometer mounted at the cantilevered end, and two laser vibrometers that simultaneously measured the responses of the base beam and the constraining layer, respectively, at the free end. A spectrum analyzer calculated frequency response functions (FRFs) between the accelerometer inputs and the vibrometer outputs. Measured FRFs of the base beam and the constraining layer were compared to detect thickness deformation. Experimental results showed that direct measurements can detect thickness deformation as low as 0.5 percent. The second goal is to evaluate the accuracy of a mathematical model developed by Miles and Reinhall [7] that accounts for thickness deformation. FRFs were calculated by using the method of distributed transfer functions by Yang and Tan [13]. Comparison of the numerical results with the experimental measurements indicated that consideration of thickness deformation can improve the accuracy of existing constrained layer damping models when the viscoelastic layer is thick.

Spurious Signals in the Thermal MEMS Gyroscope

2012 ◽  
Author(s):  
Pooneh Shooshtari ◽  
Jamal Bahari ◽  
Kourosh Khosraviani ◽  
Albert Leung ◽  
John Jones
Keyword(s):  
Mathematical Model ◽  
Fluid Flow ◽  
Linear Acceleration ◽  
Temperature Sensors ◽  
Experimental Measurements ◽  
Micro Electro Mechanical Systems ◽  
Mems Gyroscope ◽  
Two Factors ◽  
Spurious Signals ◽  
Rotation Signal

The operational principle of a thermal MEMS (Micro Electro-Mechanical Systems) gyroscope was reported in Hilton Head 2010 [1]. In the current work we describe two factors that can produce a spurious rotation signal in gyroscopes of this type. These factors are, firstly, distortion or asymmetric placement of the heating elements or temperature sensors; secondly, the effects of linear acceleration and/or gravity on the fluid flow inside the device, and hence on the gyroscope output. In order to simulate the thermal gyro and the origin of these spurious signals, a mathematical model is built and developed through the COMSOL CFD package. The spurious signals predicted by this simulation are shown to correspond to experimental measurements. Alternative cavity shapes are investigated and simulated as a mean of suppressing the spurious signal.

scholarly journals Measurement of Relative Position of Camera and Optical Beacon by Simultaneous Passive Method

2019 ◽  
Vol 8 (1) ◽  
pp. 1 ◽  
Author(s):  
Jiri Nemecek ◽  
Martin Polasek
Keyword(s):  
Mathematical Model ◽  
Relative Position ◽  
Analytical Method ◽  
Measurement Method ◽  
Position Angle ◽  
Experimental Measurements ◽  
Light Sources ◽  
Passive Measurement ◽  
Passive Method ◽  
The Mathematical Model

The paper deals with a problem of a passive measurement of the relative position of an optical beacon and an optical camera by a simultaneous analytical method. The beacon is composed of nine light sources which are arranged in space in a defined way. The proposed beacon layout enables the measurement of the beacon range and one position angle of the camera. This paper presents the mathematical model of the measurement method and the results, which were gathered on the basis of two experimental measurements. The first experiment was only indicative. The extreme results of the second experiment were as follows: the minimum and maximum absolute percentage errors of the beacon range were zero and 1.72%, the minimum and maximum errors of the position angle were 0.1 deg and 1.64 deg. The standard commercial cameras and lenses with different focal lengths were used.

scholarly journals Investigation of dynamics and power needs for container unloading from ship process

2021 ◽  
Vol 24 (1) ◽  
pp. 89-99
Author(s):  
Jolanta Janutėnienė ◽  
Marijonas Bogdevičius ◽  
Valdas Jankūnas ◽  
Jūratė Janutėnaitė-Bogdanienė ◽  
Arūnas Andziulis ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Contact Forces ◽  
Experimental Measurements ◽  
Operational Problem ◽  
Frictional Forces ◽  
Power Needs

The operational problem of container unloading from the ship is analyzed in this paper. Dynamic “crane-cargo-ship” system was investigated, and a mathematical model was created. In the model, the gap between the container and the ship’s cargo hold, the mass of the cargo, the container’s center of the mass, and the frictional forces that may occur during lifting from the cargo hold were estimated. Numerical analysis of the system was performed. Results of numerical analysis were compared with experimental measurements of containers unloading process in port. Requirement of lifting power was modelled depending on mass of cargo. Additional power needs in case of contact forces between container and wall of the ship’s cargo hold were calculated. Rational lifting conditions could be deduced using a created mathematical model and the reliability of the container and cargo during lifting could be deduced.

scholarly journals Experimental, analytical and numerical analysis of voltage distribution along the cap-and-pin insulators

2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Mladen Banjanin
Keyword(s):  
Mathematical Model ◽  
Numerical Analysis ◽  
Electrostatic Field ◽  
Field Model ◽  
Experimental Measurements ◽  
Voltage Distribution ◽  
Specialized Software ◽  
The Earth ◽  
Good Agreement ◽  
Linear Voltage

This paper deals with the experimental, analytical and numerical analysis of voltage distribution along the cap-and-pin insulators. Five different insulators strings are analyzed, consisting of two, three, four, five and six cap-and-pin U40BL glass disc insulators. Experimental measurements are performed in the high voltage laboratory at the Faculty of Electrical Engineering East Sarajevo. Measurement of the voltage distribution along the disc insulators is performed by using measuring sphere gap. Analytical calculations are performed by using mathematical model which considers parasite self-capacitances of disc insulators, as well as their parasite capacitances to the earth and to the phase conductor. Calculations of the parasite capacitances values are performed and optimum values which lead to the minimum difference between measured and calculated results are suggested. Numerical analyses of the non-linear voltage distribution are performed by using electrostatic field model in software Comsol Multyphisics. 2D axisymmetric models of the cap-and-pin insulators are developed. Despite the measuring configuration is not suitable for numerical analysis, relatively good agreement between the measured results and results calculated by using specialized software are achieved.

Fibrinolysis: Mathematical and Experimental Studies

1967 ◽  
Vol 17 (03/04) ◽  
pp. 412-417 ◽  
Author(s):  
W Liniger ◽  
P Ruegsegger
Keyword(s):  
Mathematical Model ◽  
Mathematical Simulation ◽  
Chemical Reactions ◽  
Experimental Studies ◽  
Experimental Measurements ◽  
Major Chemical ◽  
Good Agreement

SummaryIn the present paper we discuss a mathematical model of fibrinolysis, encompassing the major chemical reactions associated with this process, and show that it is in good agreement with the results of extensive experimental studies. We anticipate that such mathematical simulation, possibly combined with automation of auxiliary experimental measurements, may serve as a basis for faster and simpler clinical assays.

scholarly journals Optical Boundaries for LED-Based Indoor Positioning System

Computation ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 7 ◽  
Author(s):  
Olaoluwa Popoola ◽  
Sinan Sinanović ◽  
Wasiu Popoola ◽  
Roberto Ramirez-Iniguez
Keyword(s):  
Mathematical Model ◽  
Indoor Positioning ◽  
Experimental Measurements ◽  
Positioning System ◽  
Positioning Error ◽  
Positioning Accuracy ◽  
Light Emitting ◽  
Positioning Systems ◽  
Indoor Positioning System ◽  
Positioning Time

Overlap of footprints of light emitting diodes (LEDs) increases the positioning accuracy of wearable LED indoor positioning systems (IPS) but such an approach assumes that the footprint boundaries are defined. In this work, we develop a mathematical model for defining the footprint boundaries of an LED in terms of a threshold angle instead of the conventional half or full angle. To show the effect of the threshold angle, we compare how overlaps and receiver tilts affect the performance of an LED-based IPS when the optical boundary is defined at the threshold angle and at the full angle. Using experimental measurements, simulations, and theoretical analysis, the effect of the defined threshold angle is estimated. The results show that the positional time when using the newly defined threshold angle is 12 times shorter than the time when the full angle is used. When the effect of tilt is considered, the threshold angle time is 22 times shorter than the full angle positioning time. Regarding accuracy, it is shown in this work that a positioning error as low as 230 mm can be obtained. Consequently, while the IPS gives a very low positioning error, a defined threshold angle reduces delays in an overlap-based LED IPS.

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