Signal Shaping of Fluid Transmission Lines Using Parallel Branching

1986 ◽  
Vol 108 (4) ◽  
pp. 296-305 ◽  
Author(s):  
W. C. Yang ◽  
D. L. Margolis
Keyword(s):  
Frequency Response ◽  
Transmission Lines ◽  
Graph Model ◽  
Parallel Line ◽  
Line Length ◽  
Approximation Techniques ◽  
Frequency Domains ◽  
Line Characteristic ◽  
Fluid Transients ◽  
And Control

The dynamic characteristics of fluid transmission lines with a parallel branching line are analyzed in both time and frequency domains using modal approximation techniques which enable us to use linear system theory. For hydraulic blocked lines, root loci of dominant modes as functions of parallel line length ratio, branching location and line characteristic parameters are obtained, and also unit step and frequency responses are illustrated for various parallel line configurations. By properly adding a parallel branching line, shaping of frequency response and control of fluid transients can be accomplished in various advantageous ways, i.e., shifting the resonant frequencies, improving the resonant quality, suppressing the frequency response for particular bands of frequencies including the resonance regions, phase leading. The steady state conditions are derived in an exact manner and a modal bond graph model is presented.

Modeling of Coupled Bending and Torsion in Elastic Structures

1993 ◽  
Author(s):  
H. T. Banks ◽  
C. A. Smith
Keyword(s):  
Experimental Data ◽  
Numerical Results ◽  
Computational Results ◽  
Elastic Structures ◽  
Approximation Techniques ◽  
Flexural Vibrations ◽  
And Control

Abstract In this presentation we will report on joint efforts with D.J. Inman and his colleagues at MSL, SUNY at Buffalo, to develop viable models for the analysis and control of elastic structures exhibiting coupled torsional and flexural vibrations. A model for coupled torsion and bending is developed which incorporates Kelvin Voigt damping and warping. Approximation techniques are introduced and preliminary numerical results are discussed. Experimental data is presented and used to test our computational results.

Time and Frequency Analysis of Particle Swarm Trajectories for Cognitive Machines

2011 ◽  
Vol 5 (1) ◽  
pp. 18-42 ◽  
Author(s):  
Dario Schor ◽  
Witold Kinsner
Keyword(s):  
Particle Swarm Optimization ◽  
Parameter Space ◽  
Particle Swarm ◽  
Local Area ◽  
Complexity Measures ◽  
Swarm Optimization ◽  
Frequency Domains ◽  
Frequency Domain Techniques ◽  
And Control

This paper examines the inherited persistent behavior of particle swarm optimization and its implications to cognitive machines. The performance of the algorithm is studied through an average particle’s trajectory through the parameter space of the Sphere and Rastrigin function. The trajectories are decomposed into position and velocity along each dimension optimized. A threshold is defined to separate the transient period, where the particle is moving towards a solution using information about the position of its best neighbors, from the steady state reached when the particles explore the local area surrounding the solution to the system. Using a combination of time and frequency domain techniques, the inherited long-term dependencies that drive the algorithm are discerned. Experimental results show the particles balance exploration of the parameter space with the correlated goal oriented trajectory driven by their social interactions. The information learned from this analysis can be used to extract complexity measures to classify the behavior and control of particle swarm optimization, and make proper decisions on what to do next. This novel analysis of a particle trajectory in the time and frequency domains presents clear advantages of particle swarm optimization and inherent properties that make this optimization algorithm a suitable choice for use in cognitive machines.

scholarly journals Design and Validation of a Wide Area Monitoring and Control System for Fast Frequency Response

2020 ◽  
Vol 11 (4) ◽  
pp. 3394-3404 ◽  
Author(s):  
Qiteng Hong ◽  
Mazaher Karimi ◽  
Mingyu Sun ◽  
Sean Norris ◽  
Oleg Bagleybter ◽  
...  
Keyword(s):  
Control System ◽  
Frequency Response ◽  
Wide Area ◽  
Monitoring And Control ◽  
Monitoring And Control System ◽  
Wide Area Monitoring ◽  
And Control ◽  
Area Monitoring

Coupled microstrip filters on multilayered dielectric media

2002 ◽  
Vol 80 (6) ◽  
pp. 675-685
Author(s):  
Ar. Koufogiannidis ◽  
K Siakavara
Keyword(s):  
Frequency Response ◽  
Transmission Lines ◽  
Insertion Loss ◽  
Design Procedure ◽  
Multiconductor Transmission Lines ◽  
Microstrip Lines ◽  
Dielectric Media ◽  
Microstrip Filters ◽  
Loss Method ◽  
Good Agreement

The work presented in this paper is an attempt to design filters with coupled microstrip lines on multilayered dielectric media using methods employed in other applications. A procedure was formulated for designing filters with the desired frequency response and smaller size using insertion loss method combined with the theory of multiconductor transmission lines. The frequency response was verified by considering that the filters act as cascaded four-port networks. The results were in a very good agreement with those expected from the theoretically design procedure. PACS No.: 84.40D

Experimental validation on the integrated design and control of a parallel robot

Robotica ◽  
2005 ◽  
Vol 24 (2) ◽  
pp. 173-181 ◽  
Author(s):  
Qing Li
Keyword(s):  
Dynamic Model ◽  
High Speed ◽  
Dynamic Models ◽  
Integrated Design ◽  
Parallel Robot ◽  
Parallel Robots ◽  
Approximation Techniques ◽  
Control Approach ◽  
Modeling Errors ◽  
And Control

Due to the demands from the robotic industry, robot structures have evolved from serial to parallel. The control of parallel robots for high performance and high speed tasks has always been a challenge to control engineers. Following traditional control engineering approaches, it is possible to design advanced algorithms for parallel robot control. These approaches, however, may encounter problems such as heavy computational load and modeling errors, to name it a few. To avoid heavy computation, simplified dynamic models can be obtained by applying approximation techniques, nevertheless, performance accuracy will suffer due to modeling errors. This paper suggests applying an integrated design and control approach, i.e., the Design For Control (DFC) approach, to handle this problem. The underlying idea of the DFC approach can be illustrated as follows: Intuitively, a simple control algorithm can control a structure with a simple dynamic model quite well. Therefore, no matter how sophisticate a desired motion task is, if the mechanical structure is designed such that it results in a simple dynamic model, then, to design a controller for this system will not be a difficult issue. As such, complicated control design can be avoided, on-line computation load can be reduced and better control performance can be achieved. Through out the discussion in the paper, a 2 DOF parallel robot is redesigned based on the DFC concept in order to obtain a simpler dynamic model based on a mass-balancing method. Then a simple PD controller can drive the robot to achieve accurate point-to-point tracking tasks. Theoretical analysis has proven that the simple PD control can guarantee a stable system. Experimental results have successfully demonstrated the effectiveness of this integrated design and control approach.

Rational Polynomial Transfer Function Approximations for Fluid Transients in Lines

2003 ◽  
Author(s):  
Patompong Wongputorn ◽  
David A. Hullender ◽  
Robert L. Woods
Keyword(s):  
Exact Solution ◽  
Transmission Lines ◽  
Transfer Functions ◽  
Viscous Friction ◽  
Total System ◽  
Nonlinear Frequency ◽  
Maximum Frequency ◽  
Rational Polynomial ◽  
Curve Fit ◽  
Fluid Transients

This paper introduces a simple approach utilizing MATLAB® computational tools for generating rational polynomial transfer functions for fluid transients in both liquid and gas fluid transmission lines. These transfer functions are obtained by curve fitting in the frequency domain the exact solution to the distributed parameter laminar flow “Dissipative Model” for fluid transients that includes nonlinear frequency dependent viscous friction terms as well as heat transfer effects in gas lines. These transfer functions are formulated so they are applicable to arbitrary line terminations and so they can be inserted directly into SIMULINK® models for time domain simulation and analysis of a total system of which the fluid lines are only internal components. The inputs to the algorithm are the internal radius and length of the line; the kinematic viscosity, density, Prandtl number, and speed of sound of the fluid; and the maximum frequency to which an accurate curve fit of the exact solution is desired. This maximum frequency normally is equal to or greater than the bandwidth of the other components in the total system to be analyzed or the maximum frequency associated with the input. The simplicity of use and accuracy in the results of the exact solution representations are demonstrated for examples of a blocked fluid line and of a line terminating into a tank. The computational algorithms are available for download from the Author’s web site. This is the first of two papers pertaining to transfer functions for fluid transients. The second paper pertains to formulating simulation diagrams for total systems containing fluid lines represented by rational polynomial transfer functions.

The Generalized Response of Servovalve-Controlled, Single-Rod, Linear Actuators and the Influence of Transmission Line Dynamics

1984 ◽  
Vol 106 (2) ◽  
pp. 157-162 ◽  
Author(s):  
J. Watton
Keyword(s):  
Transmission Line ◽  
Frequency Response ◽  
System Design ◽  
Dynamic Behavior ◽  
Transmission Lines ◽  
Fatigue Testing ◽  
Open Loop ◽  
Linear Actuators ◽  
Probable Type

The open-loop response of servovalve-controlled single-rod linear actuators in investigated for both the extending and retracting cases. A linearized frequency response technique is used to establish the probable type of dynamic behavior. Nondimensional results are presented as an aid to system design, and a boundary is established such that a simplified approximation may be used. A particular class of system is then examined where interconnecting transmission lines would be important, and the techniques previously used are modified accordingly. The techniques are verified with a precision actuator developed for fatigue testing of vehicle and airframe systems.

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