共查询到20条相似文献,搜索用时 15 毫秒
1.
Christoph Zach Werner Mack Gabriele Fruhmann Werner Tieber 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(11):981-999
A comparative study of the performance of three rheological automotive shock absorber models as well as of an extended force-velocity relation in full vehicle simulation is performed. Simulation results for both the shock absorber test rig and a full vehicle crossing a single obstacle are compared with measured data. While the gain of accuracy by the extended force-velocity relation is marginal, the rheological models in general yield a noticeable improvement, which, however, in full vehicle simulation is less significant than in test rig simulation. Among the rheological models studied here, the one consisting of a nonlinear spring-dashpot element with an element modelling friction by a continuous transition from the compression to the extension range in parallel and a quadratic approximation of the static gas force exhibits the best global performance. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):229-238
In the case of full vehicle models, the technique of multi-body simulation (MBS) is frequently used to study their highly non-linear dynamic behaviour. Many non-linearities in vehicle models are induced by force elements like springs, shock absorbers, bushings and tires. Commonly, spline functions are used to represent the force responses of these components. If the non-linear relationships are more complicated, the spline approximations are no more accurate. An alternative approach is based on empirical neural networks which are based on the mathematical approximation of measured data. It is well known that neural networks are able to represent and predict complex component responses accurately. The aim of this paper is to perform a dynamic full vehicle simulation using a thermomechanically coupled hybrid neural network shock absorber model. In this shock absorber model, the spline approach is combined with a temperature-dependent neural network. Based on a displacement-controlled excitation on a four post test rig in the ADAMS/Car MBS software, a rugged test track is simulated. In this way, the front and rear shock absorbers are dynamically loaded with comfort-relevant frequencies in the range of 0.75–30 Hz and velocity amplitudes up to 2 m/s. By the simulation, stability of the hybrid neural network model is demonstrated. Furthermore, the damping force, the vertical acceleration of the chassis and the required simulation times are compared. The standard spline approach is used as a reference. 相似文献
3.
V. Pracny M. Meywerk A. Lion 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2008,46(3):229-238
In the case of full vehicle models, the technique of multi-body simulation (MBS) is frequently used to study their highly non-linear dynamic behaviour. Many non-linearities in vehicle models are induced by force elements like springs, shock absorbers, bushings and tires. Commonly, spline functions are used to represent the force responses of these components. If the non-linear relationships are more complicated, the spline approximations are no more accurate. An alternative approach is based on empirical neural networks which are based on the mathematical approximation of measured data. It is well known that neural networks are able to represent and predict complex component responses accurately. The aim of this paper is to perform a dynamic full vehicle simulation using a thermomechanically coupled hybrid neural network shock absorber model. In this shock absorber model, the spline approach is combined with a temperature-dependent neural network. Based on a displacement-controlled excitation on a four post test rig in the ADAMS/Car MBS software, a rugged test track is simulated. In this way, the front and rear shock absorbers are dynamically loaded with comfort-relevant frequencies in the range of 0.75-30 Hz and velocity amplitudes up to 2 m/s. By the simulation, stability of the hybrid neural network model is demonstrated. Furthermore, the damping force, the vertical acceleration of the chassis and the required simulation times are compared. The standard spline approach is used as a reference. 相似文献
4.
Viktor Skrickij Dzmitry Savitski Valentin Ivanov Paulius Skačkauskas 《International Journal of Automotive Technology》2018,19(5):801-810
The paper investigates cavitation effect which negatively influences the performance of a monotube shock absorber of road vehicle (passenger car). For better understanding of this phenomena, three physical models of shim stack valves are analyzed. Validation results allowed selecting the most appropriate valve model in presence of cavitation processes. A mathematical model of monotube damper with consideration of fluid compressibility and cavitation phenomena is developed. Simulation results are validated by experimental data obtained on hydraulic test rig. Based on the selected approach, a simplified method suitable for assessment of cavitation processes in automotive monotube shock absorbers is proposed. After investigation it is found that damping force when cavitation occurs mainly depends on the initial pressure and absorber inner diameter. 相似文献
5.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(6):415-432
Summary The possibility of improving the results of a rough road simulation by a - compared to the classic forcevelocity relation - more complex, but still an easy-to-handle shock absorber model based only on standard harmonic excitation test data is investigated. While a force-displacement-velocity relation proves not well suited for the problem under consideration, a force-velocity-acceleration relation yields a noticeable gain of accuracy with little effort. Special attention is given to the problems arising particularly in a full vehicle simulation. 相似文献
6.
M. Weigel W. Mack A. Riepl 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2002,38(6):415-432
Summary The possibility of improving the results of a rough road simulation by a - compared to the classic forcevelocity relation - more complex, but still an easy-to-handle shock absorber model based only on standard harmonic excitation test data is investigated. While a force-displacement-velocity relation proves not well suited for the problem under consideration, a force-velocity-acceleration relation yields a noticeable gain of accuracy with little effort. Special attention is given to the problems arising particularly in a full vehicle simulation. 相似文献
7.
Damper Models for Heavy Vehicle Ride Dynamics 总被引:18,自引:0,他引:18
F. H. Besinger D. Cebon D. J. Cole 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1995,24(1):35-64
A laboratory rig for testing hydraulic dampers using the 'hardware-in-the-loop' method is described, and the accuracy of the test method is investigated. A mathematical model of a hydraulic shock absorber is then developed. The model is suitable for vehicle simulations and has seven parameters which can be determined by simple dynamic measurements on a test damper. The shock absorber model is validated under realistic operating conditions using the test rig, and the relative importance of various features of the model on the accuracy of vehicle simulations is investigated. 相似文献
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SUMMARY A laboratory rig for testing hydraulic dampers using the ‘hardware-in-the-loop’ method is described, and the accuracy of the test method is investigated. A mathematical model of a hydraulic shock absorber is then developed. The model is suitable for vehicle simulations and has seven parameters which can be determined by simple dynamic measurements on a test damper. The shock absorber model is validated under realistic operating conditions using the test rig, and the relative importance of various features of the model on the accuracy of vehicle simulations is investigated. 相似文献
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麦弗逊悬架减振器侧向力对减振器寿命和悬架性能影响很大,系统分析减振器侧向力对麦弗逊悬架设计具有重要意义。减振器的侧向力取决于车辆运动时受到的地面的作用力和悬架的几何结构,本文综述了车辆行驶时车轮上下运动的侧向力、加速、减速、转弯时侧向力的分析,确定了麦弗逊悬架的几何结构对减振器侧向力的影响因素,并通过国内外最新产品的实例说明通过改变悬架的几何结构来减小减振器侧向力的具体方法和产生的效果。最后对减振器侧向力进行了总结,并对未来麦弗逊悬架的研发工作提出了一些建议。 相似文献
12.
A Thermomechanically Coupled Model for Automotive Shock Absorbers: Theory, Experiments and Vehicle Simulations on Test Tracks 总被引:1,自引:0,他引:1
Alexander Lion Swenja Loose 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2002,37(4):241-261
In the development of cars numerical simulation plays a more and more important role. A method commonly used in this context is based on the formalism of multibody dynamics. In this approach a vehicle is described as a system of rigid bodies connected by joints, bushings, springs and dampers. For the purpose of estimating the time-dependent dynamical loads when riding, for example, over potholes or other obstacles we need enhanced models representing the mechanical behavior of the shock absorbers. A model of this type should describe the nonlinear rate dependence of the force in combination with friction effects and thermomechanical coupling phenomena. Due to the dissipation of energy the temperature of the shock absorber increases and influences its damping behavior. When riding over long rugged test tracks these effects are strongly pronounced. Thus we develop a thermomechanical model representing all these phenomena with good approximation and being compatible with the natural laws of thermodynamics. To validate the theory, we investigate the thermomechanical behavior of two automotive shock absorbers in detail. We measure the velocity dependence of the force under different temperature levels as well as the dissipative change in the temperature during cyclic excitations. Finally we carry out a vehicle test on a rugged test track and record the temperature of the front and rear dampers. As we show, the model describes all phenomena with sufficient approximation, especially the evolution of temperature. 相似文献
13.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):241-261
In the development of cars numerical simulation plays a more and more important role. A method commonly used in this context is based on the formalism of multibody dynamics. In this approach a vehicle is described as a system of rigid bodies connected by joints, bushings, springs and dampers. For the purpose of estimating the time-dependent dynamical loads when riding, for example, over potholes or other obstacles we need enhanced models representing the mechanical behavior of the shock absorbers. A model of this type should describe the nonlinear rate dependence of the force in combination with friction effects and thermomechanical coupling phenomena. Due to the dissipation of energy the temperature of the shock absorber increases and influences its damping behavior. When riding over long rugged test tracks these effects are strongly pronounced. Thus we develop a thermomechanical model representing all these phenomena with good approximation and being compatible with the natural laws of thermodynamics. To validate the theory, we investigate the thermomechanical behavior of two automotive shock absorbers in detail. We measure the velocity dependence of the force under different temperature levels as well as the dissipative change in the temperature during cyclic excitations. Finally we carry out a vehicle test on a rugged test track and record the temperature of the front and rear dampers. As we show, the model describes all phenomena with sufficient approximation, especially the evolution of temperature. 相似文献
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扭转梁后桥开发过程中,须按照从整车技术要求分解出的零部件技术规范进行设计,并借助CAE优化技术对零部件各性能进行优化。本文主要针对某型扭转梁后桥侧向力耐久疲劳和减振器力耐久疲劳工况进行优化分析,结构优化后耐久疲劳寿命提高。实物样件台架验证结果与优化仿真分析结果基本一致。 相似文献
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针对某车型整车道路试验过程中出现的后减振器上支座失效问题,通过查看分析故障件的失效状态,结合应用Abaqus软件进行CAE仿真分析,确定了其失效的主要原因是由于在整车运动过程中,上支座衬套的橡胶凸台的应力太大。对此提出了改进的设计方案,通过台架试验和整车道路试验的验证,结果表明,改进后的后减振器上支座解决了耐久失效问题,同时经整车NVH和操稳性能评价后确认改进方案未对整车性能产生不利影响。 相似文献
18.
Evaluation of Shock Absorber Models 总被引:16,自引:0,他引:16
Stefaan Duym Randy Stiens Koenraad Reybrouck 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1997,27(2):109-127
A non exhaustive overview of shock absorber models is presented. The ability of the models to match experimental data is emphasized. Two physical models are presented that are able to extract the internal valve parameters from data without hysteresis. In order to implement a model that copes with hysteresis, most models require the numerical solution to a set of nonlinear differential equations. The use of an alternative restoring force method can get round the time consuming iterative simulation and identification routines. The alternative nonparametric method models the force as a function of velocity and acceleration. The theoretical relevance of the model is studied. 相似文献
19.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):387-401
In recent years so-called ‘virtual test rigs’ have become more and more important in the development process of cars and trucks. Originally, the idea was to substitute expensive durability tests with computer simulation. Meanwhile, the focus has changed towards a more cooperative usage of numerical and laboratory rig simulation. For many safety critical issues laboratory tests remain indispensable. In early development stages, when no physical prototypes are available yet, numerical simulation is used to analyse and optimise the design. In this paper, we show how to build numerical simulation models of complex servo-hydraulic test systems and their test specimen using multi-body simulation for the mechanics in combination with simulation models for the hydraulics and controls. We illustrate this at two industrial application examples: a spindle-coupled passenger car suspension rig and a tyre-coupled full vehicle rig. We show how the simulation models are used to design and optimise better test rigs and to support the test rig operation by preparing the physical tests with new specimen, i.e. by performing numerical simulations including numerical drive file iteration before the physical tests start. 相似文献
20.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1066-1098
This paper qualitatively and quantitatively reviews and compares three typical tyre–road friction coefficient estimation methods, which are the slip slope method, individual tyre force estimation method and extended Kalman filter method, and then presents a new cost-effective tyre–road friction coefficient estimation method. Based on the qualitative analysis and the numerical comparisons, it is found that all of the three typical methods can successfully estimate the tyre force and friction coefficient in most of the test conditions, but the estimation performance is compromised for some of the methods during different simulation scenarios. In addition, all of these three methods need global positioning system (GPS) to measure the absolute velocity of a vehicle. To overcome the above-mentioned problem, a novel cost-effective estimation method is proposed in this paper. This method requires only the inputs of wheel angular velocity, traction/brake torque and longitudinal acceleration, which are all easy to be measured using available sensors installed in passenger vehicles. By using this method, the vehicle absolute velocity and slip ratio can be estimated by an improved nonlinear observer without using GPS, and the friction force and tyre–road friction coefficient can be obtained from the estimated vehicle velocity and slip ratio. Simulations are used to validate the effectiveness of the proposed estimation method. 相似文献