Method for the quasi-static analysis of beam axle suspension systems used for road vehicles

Author(s):  
Cătălin Alexandru

This paper addresses an analytical method for determining the static equilibrium position of beam axle suspension systems used of motor vehicles. This method is applicable to most types of suspension systems and is based on the definition of the spatial positioning of the guiding mechanism as a result of the forces and torques acting in the suspension system. The static model is defined in analytical form, in terms of virtual work, considering the system of applied forces and reactions in the elastic suspension elements (springs, bumpers, anti-roll bar and bushings), whose deformations are determined by the spatial positioning of the guiding mechanism. The proposed method is based on an iterative algorithm by which, for a given set of contact forces on wheels, the equilibrium position is identified by scanning the entire vertical motion domain of the wheels and selecting the configuration that ensures minimal static function. The results obtained by the algorithmization of the method and computer programming allow an accurate assessment of the static behaviour of a beam axle suspension system (in terms of equilibrium configuration and reaction forces) in various regimes, without the need for costly experimental testing.

2013 ◽  
Vol 471 ◽  
pp. 14-19 ◽  
Author(s):  
Zulkifli Nawawi ◽  
Nurazima Ismail ◽  
Ahmad Razlan Yusoff

This paper investigates the effect of vibration and vehicle body movements acting on the vehicles wheel due to the different damping characteristics of suspension systems. Three different damping characteristics damper named Absorber A, Absorber B and Absorber C was installed on the suspension system of the Proton Persona which was used as a test car. This test car was equipped with accelerometers and wire potentiometer sensor on the front and rear suspensions, gyroscopic, Global Positioning System (GPS) and connect with DEWEsoft software as a data acquisition. To study the effect of three different damper characteristics on suspension system, the ride comfort analysis and car body movement analysis were used to analyze the result during experimental testing. There were 3 maneuver testing experiment were performed including steady-state cornering, single-lane change and slalom testing experiment. Based on the results, comparison between the suspension damper characteristics due to the driving maneuvers and car movement were made and their performance also were ranked. Absorber A was the hardest damper as compared to Absorber C and Absorber B according to the damping constant value. The result showed that the best performance for car movement made by Absorber A then followed by Absorber C and Absorber B, while the best performance for ride comfort analysis was made by Absorber B followed by Absorber C and A.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Zhi-Jun Fu ◽  
Bin Li ◽  
Xiao-Bin Ning ◽  
Wei-Dong Xie

In view of the performance requirements (e.g., ride comfort, road holding, and suspension space limitation) for vehicle suspension systems, this paper proposes an adaptive optimal control method for quarter-car active suspension system by using the approximate dynamic programming approach (ADP). Online optimal control law is obtained by using a single adaptive critic NN to approximate the solution of the Hamilton-Jacobi-Bellman (HJB) equation. Stability of the closed-loop system is proved by Lyapunov theory. Compared with the classic linear quadratic regulator (LQR) approach, the proposed ADP-based adaptive optimal control method demonstrates improved performance in the presence of parametric uncertainties (e.g., sprung mass) and unknown road displacement. Numerical simulation results of a sedan suspension system are presented to verify the effectiveness of the proposed control strategy.


2021 ◽  
Vol 263 (4) ◽  
pp. 2654-2664
Author(s):  
Wout Schwanen ◽  
Mark Mertens ◽  
Ysbrand Wijnant ◽  
Willem Jan van Vliet

The noise reduction of a (low) noise barrier can be enhanced by using an additional element with quarter-wavelength resonators with varying depths. The so-called WHISwall or WHIStop deflects sound upwards for specific frequencies creating an additional sound reduction. Different experiments on the WHISwall and WHIStop are performed as input for model validation. The development and validation of the model are described in a separate paper. In this paper the measurement campaign and its results are presented. We performed measurements on two setups. The first setup consists of a 1.1 meter high WHISwall, a 1.1m high noise barrier and a reference section (without noise measure). Measurements have been conducted with both an artificial sound source and pass by measurements with light and heavy motor vehicles. In a second test setup, the WHIStop was placed on top of a 4 meter high noise barrier and the diffraction was determined according the European standard EN 1793-4.


2020 ◽  
pp. 107754632097290
Author(s):  
You-cheng Zeng ◽  
Hu Ding ◽  
Rong-Hua Du ◽  
Li-Qun Chen

In this article, a novel vibration control scheme of suspension systems is proposed. It combines the advantages of quasi-zero stiffness isolator, nonlinear energy sink absorber, and inerter. This proposed scheme can achieve low transmissibility, low amplitude, and low additional weight and resolve the conflict between riding comfort and handling stability. Strong nonlinear vibration equations of a quarter-vehicle suspension system are established. It also presents the detailed process of high-order harmonic approximation to obtain steady-state responses. Moreover, approximate solutions are validated by a numerical method. Furthermore, based on riding comfort and handling stability, the following four suspension systems are evaluated and compared, namely, 2-degree-of-freedom quarter-vehicle model, 2-degree-of-freedom quarter-vehicle with quasi-zero stiffness isolator, 2-degree-of-freedom quarter-vehicle with inerter-nonlinear energy sink absorber, and 2-degree-of-freedom quarter-vehicle integrated control scheme with quasi-zero stiffness and inerter-nonlinear energy sink. It is found that the integrated control scheme with quasi-zero stiffness and inerter-nonlinear energy sink can significantly improve the riding comfort and handling stability at the same time. In addition, the effects of system parameters are studied carefully. The results show that based on the reasonable design of the control system parameters, better riding comfort and handling stability can be obtained. In short, this article provides a theoretical basis for integrating quasi-zero stiffness isolators and inerter-nonlinear energy sink absorbers to improve the riding comfort and handling stability.


2019 ◽  
Vol 26 (11-12) ◽  
pp. 952-964 ◽  
Author(s):  
Wu Qin ◽  
Wen-Bin Shangguan ◽  
Kegang Zhao

Based on a nonlinear two-degree-of-freedom model of active suspension systems, an approach of the sliding mode control with disturbance observer combining skyhook model sliding mode control with disturbance observer combining is proposed for improving the performance of active suspension systems, and the effectiveness of the proposed approach is validated by the active suspension system plant. Two problems of active suspension systems are solved by using the proposed approach when the tire is excited by the step displacement. One problem is that the suspension deflection of active suspension systems, i.e. the difference between the sprung mass displacement and the unsprung mass displacement, using conventional sliding mode control with disturbance observer not converges to zero in finite time, and the phenomenon of the impact of suspension against the limit block is produced. This problem is solved by providing a reference value of the sprung mass displacement in an active suspension system, which is obtained from the skyhook model. The other problem is that disturbances exist in active suspension systems, which are caused by the inaccurate parameters of stiffness and damping. This problem is solved by designing a disturbance observer to estimate the summation of the disturbances. Finally, the performance indexes of the active suspension system with the sliding mode control with disturbance observer combining skyhook model are calculated and compared with those of using the conventional sliding mode control with disturbance observer and the linear quadratic regulator approach.


Author(s):  
Amit Shukla ◽  
Jeong Hoi Koo

Nonlinear active suspension systems are very popular in the automotive applications. They include nonlinear stiffness and nonlinear damping elements. One of the types of damping element is a magneto-rheological fluid based damper which is receiving increased attention in the applications to the automotive suspension systems. Latest trends in suspension systems also include electronically controlled systems which provide advanced system performance and integration with various processes to improve vehicle ride comfort, handling and stability. A control bifurcation of a nonlinear system typically occurs when its linear approximation loses stabilizability. These control bifurcations are different from the classical bifurcation where qualitative stability of the equilibrium point changes. Any nonlinear control system can also exhibit control bifurcations. In this paper, control bifurcations of the nonlinear active suspension system, modeled as a two degree of freedom system, are analyzed. It is shown that the system looses stability via Hopf bifurcation. Parametric control bifurcation analysis is conducted and results presented to highlight the significance of the design of control system for nonlinear active suspension system. A framework for the design of feedback using the parametric analysis for the control bifurcations is proposed and illustrated for the nonlinear active suspension system.


2014 ◽  
Vol 1036 ◽  
pp. 794-799 ◽  
Author(s):  
Łukasz Konieczny ◽  
Rafał Burdzik ◽  
Piotr Folęga

The paper presents results of investigation of car suspension system dynamics. In this research the multibody (Multi Body System - MBS) system software MSC.Adams was used. ADAMS software (MSC.Software) is a commercial software to build a multibody structural models. Modular design allows for the usage of applications with different focuses, such as rail, aviation and motor vehicles. Models with a large number of freedom degrees of the components are built with mass concentrated on the assumption that the system is composed of a rigid (or deformable) bodies combined in a specific way (connection spherical, sliding, rotary), moving under the action of the forces and moments of different types (concentrated or distributed forces, the forces of contact). The complex multibody systems are automatically generated by the Lagrange equations of motion of the second kind in absolute coordinates. Integral procedures used to solve the differential-algebraic equations include multistep algorithms with variable row and a variable-and fixed-step and one-step algorithms. The Adams/Car module enables building and simulation-based examination of individual car subsystems such as, for instance, the suspension, steering or driving system as well as their combinations forming a complete car. The programme contains an extensive library of structural solutions applied in cars. The geometry and relationship data of individual components are stored in libraries, and software operation on a standard user level can be brought down to defining positions of constraints in space. The software is compatible with various CAD programmes, thus enabling import of elements created in other applications. The study was conducted for the vehicle model of Fiat Seicento. The examined system of the complete vehicle consists of 49 kinematic degrees of freedom. The article examined the impact of chosen parameters on vehicle vibration in an Adams Car Ride. Used in simulation Adams/Car /Ride module allows to test vehicle dynamics forcing the position of the plate of test stand . Virtual model of the vehicle is set on four servo-motors. They can control any excitation combination of individual actuators (dispalcement and amplitude, phase between extortion, etc.) and determine all kinds of vibration (vertical, lateral, angular). The study was conducted for selected parameters of the test rig.


2017 ◽  
Vol 29 (1) ◽  
pp. 41-51 ◽  
Author(s):  
Michael McKee ◽  
Faramarz Gordaninejad ◽  
Xiaojie Wang

The temperature effect on performance of compressible magnetorheological fluid suspension systems is studied. Magnetorheological fluid is a temperature-dependent material where its compressibility and rheological properties change with temperature. Experimental studies were conducted to explore the temperature effects on the properties of the magnetorheological fluid and the compressible magnetorheological fluid suspension systems. The temperature effect on magnetorheological fluid properties included the bulk modulus, shear yield stress, and viscosity. It was found that the shear yield stress of the magnetorheological fluid remains unchanged within the testing range while both the plastic viscosity, using the Bingham plastic model, and the bulk modulus of the magnetorheological fluid decrease as the temperature of the fluid increases. A theoretical model that incorporates the temperature-dependent properties of magnetorheological fluid was developed to predict behavior of a compressible magnetorheological fluid suspension system. An experimental study was conducted using an annular flow compressible magnetorheological fluid suspension system with varying temperatures, motion frequencies, and magnetic fields. The experimental results are used to verify the theoretical model. Moreover, the stiffness and energy dissipation of the compressible magnetorheological fluid suspension system were obtained, experimentally. The effects of the temperature on performance characteristics of the compressible magnetorheological fluid suspension system were analyzed. It was found that both the stiffness and the energy dissipation decrease with an increase in the temperature of magnetorheological fluid.


1979 ◽  
Vol 101 (4) ◽  
pp. 321-331
Author(s):  
L. M. Sweet ◽  
H. C. Curtiss ◽  
R. A. Luhrs

A linearized model of the pitch-heave dynamics of a Tracked Ram Air Cushion Vehicle is presented. This model is based on aerodynamic theory which has been verified by wind tunnel and towed model experiments. The vehicle is assumed to be equipped with two controls which can be configured to provide various suspension system characteristics. The ride quality and dynamic motions of the fixed winglet vehicle moving at 330 km/hr over a guideway described by roughness characteristics typical of highways is examined in terms of the rms values of the vertical acceleration in the foremost and rearmost seats in the passenger cabin and the gap variations at the leading and trailing edges of the vehicle. The improvement in ride quality and dynamic behavior which can be obtained by passive and active suspension systems is examined and discussed. Optimal regulator theory is employed to design the active suspension system. The predicted rms values of the vertical acceleration in the one-third octave frequency bands are compared with the vertical ISO Specifications. It is shown that marked improvements in the ride quality can be obtained with either the passive or active suspension systems.


Sign in / Sign up

Export Citation Format

Share Document