A New CRONE Suspension: More Compact and More Efficient: Part 2—Synthesis and Achievement

2009 ◽  
Author(s):  
Audrey Rizzo ◽  
Xavier Moreau ◽  
Alain Oustaloup ◽  
Vincent Hernette
Keyword(s):  
Transfer Function ◽  
Fractional Derivative ◽  
Vibration Isolation ◽  
Suspension System ◽  
Technological Parameters ◽  
Stability Degree ◽  
Parallel Arrangement ◽  
The Stability ◽  
Crone Suspension ◽  
The Ideal

In a vibration isolation context, fractional derivative can be used to design suspensions which allow to obtain similar performances in spite of parameters uncertainties. This paper presents the synthesis and the achievement of a new Hydractive CRONE suspension system. After the study of the different constraint in suspension in the first paper, the ideal transfer function of the hydractive CRONE suspension is created and simulated in different case. Then a method to determine the technological parameters is proposed. A parallel arrangement of dissipative and capacitive components and a gamma arrangement are compared. They lead to the same unusual performances: the stability degree robustness and the rapidity robustness.

Synthesis of a Limited-Bandwidth Fractional Differentiator Made in Hydropneumatic Technology

2005 ◽  
Author(s):  
Pascal Serrier ◽  
Xavier Moreau ◽  
Alain Oustaloup
Keyword(s):  
Vibration Isolation ◽  
Technological Parameters ◽  
Hydraulic Test ◽  
Limited Bandwidth ◽  
Crone Control ◽  
The Stability ◽  
Control Methodology ◽  
Crone Suspension ◽  
Fractional Differentiator ◽  
Made In

In a vibration isolation context, fractional derivative can be used to design suspensions which allow to obtain similar performances in spite of parameters uncertainties. This paper presents the synthesis and the achievement of a CRONE suspension. A CRONE suspension is synthesised using the CRONE control methodology. Its transfer function is a limited bandwidth fractional differentiator. After the formulation of vibration isolation problems as control law synthesis problems, a method to determine the technological parameters of a CRONE suspension is proposed and is applied to a CRONE hydraulic test bench. A parallel arrangement of dissipative and capacitive components and a gamma arrangement are compared. They lead to the same unusual performances: the stability degree robustness and the rapidity robustness.

scholarly journals Matching, Stability, and Vibration Analysis of Nonlinear Suspension System for Truck Cabs

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Fuxing Yang ◽  
Leilei Zhao ◽  
Yuewei Yu ◽  
Changcheng Zhou
Keyword(s):  
Dynamic Simulation ◽  
Vibration Isolation ◽  
Design Space ◽  
Ride Comfort ◽  
Suspension System ◽  
Installation Space ◽  
Vibration Excitation ◽  
Cab Suspension ◽  
Simulation Results ◽  
The Stability

To improve comfort, a nonlinear suspension system is proposed on the basis of the nonlinear vibration isolation theory and the installation space of the cab suspension system for trucks. This system is suitable for all-floating cabs. For easy matching and design, the static and stability characteristics of the suspension system were analyzed, respectively, and the boundary condition for the stability of the system was given. Moreover, the cab simulation model was established, and the dynamic simulation was conducted. The stability analysis shows that the smaller the vibration excitation of the cab system, the higher its stability is. The dynamic simulation results show that the acceleration of the cab with the nonlinear suspension system is effectively suppressed; the dynamic deflection of the suspension is kept within a certain range, and the design space of the suspension stroke can be effectively utilized. Compared with the traditional linear suspension system, the nonlinear suspension system has better vibration isolation characteristics and can effectively improve ride comfort.

Possible applications of fraunhofer holography in high resolution electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 222-223 ◽  
Author(s):  
N. Bonnet ◽  
M. Troyon ◽  
P. Gallion
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Transfer Function ◽  
Radiation Damage ◽  
High Resolution Electron Microscopy ◽  
Far Field ◽  
Field Region ◽  
Crystalline Materials ◽  
Resolution Electron ◽  
The Ideal

Two main problems in high resolution electron microscopy are first, the existence of gaps in the transfer function, and then the difficulty to find complex amplitude of the diffracted wawe from registered intensity. The solution of this second problem is in most cases only intended by the realization of several micrographs in different conditions (defocusing distance, illuminating angle, complementary objective apertures…) which can lead to severe problems of contamination or radiation damage for certain specimens.Fraunhofer holography can in principle solve both problems stated above (1,2). The microscope objective is strongly defocused (far-field region) so that the two diffracted beams do not interfere. The ideal transfer function after reconstruction is then unity and the twin image do not overlap on the reconstructed one.We show some applications of the method and results of preliminary tests.Possible application to the study of cavitiesSmall voids (or gas-filled bubbles) created by irradiation in crystalline materials can be observed near the Scherzer focus, but it is then difficult to extract other informations than the approximated size.

An hourglass-type electromagnetic isolator with negative resistance electromagnetic shunt circuit

2020 ◽  
Vol 64 (1-4) ◽  
pp. 549-556
Author(s):  
Yajun Luo ◽  
Linwei Ji ◽  
Yahong Zhang ◽  
Minglong Xu ◽  
Xinong Zhang
Keyword(s):  
Vibration Isolation ◽  
Electromechanical Coupling ◽  
Coupling Effect ◽  
Negative Resistance ◽  
Isolation System ◽  
Amplitude Vibration ◽  
Vibration Responses ◽  
The Stability ◽  
Isolation Performance ◽  
Shunt Circuit

The present work proposed an hourglass-type electromagnetic isolator with negative resistance (NR) shunt circuit to achieve the effective suppression of the micro-amplitude vibration response in various advanced instruments and equipment. By innovatively design of combining the displacement amplifier and the NR electromagnetic shunt circuit, the current new type of vibration isolator not only can effectively solve the problem of micro-amplitude vibration control, but also has significant electromechanical coupling effect, to obtain excellent vibration isolation performance. The design of the isolator and motion relationship is presented firstly. The electromechanical coupling dynamic model of the isolator is also given. Moreover, the optimal design of the NR electromagnetic shunt circuit and the stability analysis of the vibration isolation system are carried out. Finally, the simulation results about the transfer function and vibration responses demonstrated that the isolator has a significant isolation performance.

Random filters which preserve the stability of random inputs

1988 ◽  
Vol 20 (2) ◽  
pp. 275-294 ◽  
Author(s):  
Stamatis Cambanis
Keyword(s):  
Transfer Function ◽  
Moving Average ◽  
Random Processes ◽  
Time Shift ◽  
Linear Filter ◽  
Random Inputs ◽  
The Stability ◽  
Non Gaussian ◽  
Random Gain

A stationary stable random processes goes through an independently distributed random linear filter. It is shown that when the input is Gaussian or harmonizable stable, then the output is also stable provided the filter&s transfer function has non-random gain. In contrast, when the input is a non-Gaussian stable moving average, then the output is stable provided the filter&s randomness is due only to a random global sign and time shift.

Dynamic analysis and control of an active engine mount system

2002 ◽  
Vol 216 (11) ◽  
pp. 921-931 ◽  
Author(s):  
Y-W Lee ◽  
C-W Lee
Keyword(s):  
Transfer Function ◽  
Dynamic Characteristics ◽  
Performance Test ◽  
Adaptive Controller ◽  
Lms Algorithm ◽  
Equivalent Mass ◽  
Engine Mount ◽  
Active Engine ◽  
The Stability ◽  
Mass Spring

Dynamic characteristics of a prototype active engine mount (AEM), designed on the basis of a hydraulic engine mount, have been investigated and an adaptive controller for the AEM has been designed. An equivalent mass-spring-damper AEM model is proposed, and the transfer function that describes the dynamic characteristics of the AEM is deduced from mathematical analysis of the model. The damping coefficient of the model is derived by considering the non-linear flow effect in the inertia track. Experiments confirmed that the model precisely describes the dynamic characteristics of the AEM. An adaptive controller using the filtered-X LMS algorithm is designed to cancel the force transmitted through the AEM. The stability of the LMS algorithm is guaranteed by using the secondary path transfer function derived on the basis of the dynamic model of the AEM. The performance test in the laboratory shows that the AEM system is capable of significantly reducing the force transmitted through the AEM.

IDENTIFICATION OF VISCOELASTIC MODEL OF FOUR-WIRE SUSPENSION SYSTEM IN OPTICAL PICKUP ACTUATOR

2017 ◽  
Vol 41 (5) ◽  
pp. 731-744
Author(s):  
Ren J. Chang ◽  
Zheng Y. Liu
Keyword(s):  
Transfer Function ◽  
Fractional Derivative ◽  
Dynamic Model ◽  
Classical Model ◽  
Viscoelastic Model ◽  
Optical Pickup ◽  
Static Tests ◽  
Wire Suspension ◽  
Suspension Structure ◽  
Sinusoidal Excitation

A novel viscoelastic model of four-wire suspension structure with damping gel in an optical pickup actuator was identified and validated. A two-stage method was developed for the identification of inertia, damping, and spring parameters in the dynamic model. The inertia and spring parameters were identified from static tests. With the identified parameters in the dynamic model, the damping parameters were identified through sinusoidal excitation tests. The accuracy of utilizing fractional derivative to model the damping of polymer damper was validated by carrying out error analysis. The fractional transfer function with voltage input was identified and compared with the transfer function of classical model.

The CRONE Suspension: Modelling and Stability Analysis

2003 ◽  
Author(s):  
Xavier Moreau ◽  
Olivier Altet ◽  
Alain Oustaloup
Keyword(s):  
Stability Analysis ◽  
Transfer Function ◽  
Design Methodology ◽  
Control Design ◽  
Internal Stability ◽  
Function Modelling ◽  
Robust Control Design ◽  
Force Displacement ◽  
Crone Suspension ◽  
Transfer Function Modelling

The CRONE suspension, French acronym of “suspension a` Comportement Robuste d’Ordre Non Entier”, results from a traditional suspension system whose spring and damper are replaced by a mechanical and hydropneumatic system defined by a fractional (so-called non-integer) order force-displacement transfer function. Modelling, frequency-domain robust control design methodology and internal stability analysis are presented in this paper.

A New CRONE Suspension: More Compact and More Efficient: Part 1—Problematics and Specifications

2009 ◽  
Author(s):  
Audrey Rizzo ◽  
Xavier Moreau ◽  
Alain Oustaloup ◽  
Vincent Hernette
Keyword(s):  
Suspension System ◽  
Technological Structure ◽  
Set Up ◽  
Crone Suspension

This paper presents, in 2 parts, a new CRONE suspension approach. The first part defines the problematics in suspension and gives the different conditions to overcome it. Then in the second paper a new CRONE suspension system is synthesized based on the conclusion of this paper. So, here, is presented how the variations of mass act on the classical suspension and how tools can be set up to simulate the influence of this variation without to choose the technological structure. Then a criterion on the level of wheel holding is established.

scholarly journals Modified Kawahara equation within a fractional derivative with non-singular kernel

2018 ◽  
Vol 22 (2) ◽  
pp. 789-796 ◽  
Author(s):  
Devendra Kumar ◽  
Jagdev Singh ◽  
Dumitru Baleanu
Keyword(s):  
Fractional Derivative ◽  
Numerical Solution ◽  
Water Waves ◽  
Iterative Scheme ◽  
Singular Kernel ◽  
Kawahara Equation ◽  
Long Wavelength ◽  
Exponential Kernel ◽  
The Stability ◽  
Linear Water Waves

The article addresses a time-fractional modified Kawahara equation through a fractional derivative with exponential kernel. The Kawahara equation describes the generation of non-linear water-waves in the long-wavelength regime. The numerical solution of the fractional model of modified version of Kawahara equation is derived with the help of iterative scheme and the stability of applied technique is established. In order to demonstrate the usability and effectiveness of the new fractional derivative to describe water-waves in the long-wavelength regime, numerical results are presented graphically.

Sign in / Sign up

Export Citation Format

Share Document