Variable-damping-based semiactive control: Analogy between structural and suspension systems

Author(s):  
Akira Nishitani ◽  
Yoshihiro Nittta
1996 ◽  
Vol 2 (3) ◽  
pp. 349-368 ◽  
Author(s):  
Y. Cai ◽  
S.S. Chen

This study investigates alternate designs for control of maglev vehicle suspension systems. Active and semiactive control-law designs are introduced into primary and secondary suspensions of maglev vehi cles. A one-dimensional vehicle with two degrees of freedom, simulating the German Transrapid Magiev System, is used. The transient and frequency responses of suspension systems and power spectral densities of vehicle accelerations are calculated to evaluate different control designs. The results show that both active and semiactive control designs improve vehicle response and provide acceptable ride comfort for maglev systems.


Suspension systems are designed for the increase in comfort and stability in vehicles while driving. Parameter changes in these systems affect overall performance. Researchers are continuously working on the performance enhancement of suspension systems by designing dampers of variable damping coefficient. In this research work a quarter car model suspension system was developed to demonstrate experimentally the influence of changing the damping coefficient, the stiffness, and the loading level to fully understand the allowable combination of parameters for a smoother ride. A variety of different test scenarios are implemented to the system to observe the variations in damping ratio. The damping ratio of the system found to be dependent on the design of the opening mechanism.The valve opening methods can give different results with the same parameters.


2019 ◽  
Vol 26 (4) ◽  
pp. 185-196
Author(s):  
Adrian Ioan Niculescu ◽  
Antoni Jankowski ◽  
Miroslaw Kowalski ◽  
Tudor Sireteanu

AbstractThe paper presents a review of the suspension solutions used on the street vehicle up to the now a days, finalising with presentation of their damping characteristics and with evaluation of their advantages or disadvantages. Long time the suspension systems have been dominated by the classic passive suspensions realized with metallic springs, shock absorbers with constant damping coefficients and anti-roll bars, excepting some luxury and sport cars using semi-active and active suspensions. There are presented some semi-active suspension solutions with continuous or discontinuous damping characteristics adjustment and the evolution of the Citroen and other active suspensions. All of them improve in some matter the performances but all of them have not ability to recuperate energy and has auxiliary energy consumption so last period the electromagnetically shock absorbers are researched, the paper presenting some of them. The paper also presents magneto rheological MR damper, solutions for adjustable passive shock absorbers and solutions for passive shock absorbers with variable damping coefficient with the stroke, e.g. Monroe Sensa Trac, Citroën Solution and VZN solution, with their damping characteristics and performances.


2011 ◽  
Vol 338 ◽  
pp. 622-625 ◽  
Author(s):  
Yao Jung Shiao ◽  
Yao Kuan Huang

Conventional oil dampers are non-controllable passive dampers because the viscosity of the fluid used is not wide-range variable. By using magneto-rheological fluid (MRF), MRF damper has excellent performance for variable-damping applications. Due to the single-coil design in the general MRF damper, the obtained damping from MR effect is not quite large. This research provides a high-damping MRF damper by adopting multi-pole coil and special polarization configuration. The simulated results show that the new MRF damper has good performance in the magnetic field and damping. Compared with a similar-size general single-coil MRF damper, this new MRF damper can get 47% higher performance under the same operating conditions.


2005 ◽  
Vol 127 (5) ◽  
pp. 493-502 ◽  
Author(s):  
Xubin Song ◽  
Mehdi Ahmadian ◽  
Steve Southward ◽  
Lane R. Miller

In this paper, we will present a nonlinear-model-based adaptive semiactive control algorithm developed for magnetorheological (MR) suspension systems exposed to broadband nonstationary random vibration sources that are assumed to be unknown or not measurable. If there exist unknown and∕or varying parameters of the dynamic system such as mass and stiffness, then the adaptive algorithm can include on-line system identification such as a recursive least-squares method. Based on a nonparametric MR damper model, the adaptive system stability is proved by converting the hysteresis inherent with MR dampers to a memoryless nonlinearity with sector conditions. The convergence of the adaptive system, however, is investigated through a linearization approach including further numerical illustration of specific cases. Finally the simulation results for a magnetorheological seat suspension system with the suggested adaptive control are presented. The results are compared with low-damping and high-damping cases, and such comparison further shows the effectiveness of the proposed nonlinear model-based adaptive control algorithm for damping tuning.


2000 ◽  
Vol 28 (2) ◽  
pp. 119-137 ◽  
Author(s):  
P. Lemerle ◽  
P. Mistrot

Abstract Counterbalance trucks are machines in widespread use in every industrial sector. Unlike cars, they are not designed with suspension systems. Consequently, they are considered to be high vibrating vehicles. Nevertheless, like suspension seats, tires can be selected as suspension parts. This paper presents a new numerical model for the analysis of the vibratory behavior of counterbalance truck tires. This model was intended to be a part of a fork lift truck model, including axles, chassis, and cabin. All the results reported here show a close agreement between measurements and numerical simulations. Thus, it can predict the vibration emission values at the driving position and is used to compare the efficiency of solid tires with pneumatic tires in terms of transmitted vibration levels.


Alloy Digest ◽  
1998 ◽  
Vol 47 (5) ◽  

Abstract Inland DuraSpring is a high-strength microalloyed spring steel for use in high stress coil springs for automobile and light truck suspension systems. This bar product offers significant improvements in tensile strength, fatigue properties, and fracture toughness compared to conventional spring steels. This datasheet provides information on composition, hardness, and tensile properties as well asfracture toughness and fatigue. Filing Code: SA-496. Producer or source: Ispat Inland Inc.


2020 ◽  
Vol 53 (2) ◽  
pp. 14407-14412
Author(s):  
G. BEL HAJ FREJ ◽  
X. MOREAU ◽  
E. HAMROUNI ◽  
A. BENINE-NETO ◽  
V. HERNETTE

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