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1.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(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
2.
《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.
《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
5.
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
6.
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
7.
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
8.
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
9.
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
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《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
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J. A. Calvo V. Díaz J. L. San Román D. García-Pozuelo 《International Journal of Automotive Technology》2008,9(4):467-472
In order to safely maintain a vehicle, it is necessary to verify the most important systems that affect safety during Periodic
Motor Vehicle Inspections (PMVIs). In a previous paper, a test method and validation criteria were suggested by the authors
to verify shock absorber status during PMVIs, as they are a fundamental component that may wear out during a vehicle’s life.
In this paper, variations of the performance of the vehicle’s brakes resulting from shock absorber wearing have been analyzed,
in order to confirm whether the suggested criteria is valid for taking into account longitudinal forces and pitch movement
on the vehicle. A simulation-based study was conducted with several configurations of a worn damper on a vehicle driving on
two virtual roads: smooth and undulating. The results confirmed that the damping coefficient established as an acceptable
value to verify the shock absorber status in PMVIs is also valid considering the forces involved in a braking maneuver. 相似文献
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《JSAE Review》1999,20(4):505-510
The ride and handling qualities of conventional delivery trucks are wores compared to modern passenger cars. However this vehicles have the power to drive as fast as passenger cars. Vehicle comfort and driving safety are mostly influenced by vertical accelerations and vehicle movements caused by pitch and roll motions. In the paper “Vehicle Dynamics with Adaptive or Semi-Active Suspension Systems – Demands on Software and Hardware” Wallentowitz and Ridlich have shown at AVEC'94 in which way tyre stiffness, shock absorber characteristics, spring stiffness and unsprung mass have an influence on vehicle comfort and active safety. They achieved these results by the theoretical analysis of a quarter-vehicle-model. Their examinations are extended in this paper on the model of a complete delivery truck. By the use of the multibody-simulation tool SIMPACK the road performance of a delivery truck will be analysed. Therefore a complex model of the vehicle has been built up in SIMPACK. Several computer simulations have been carried out to analyse the vehicle comfort and handling characteristics in different standard driving manoeuvres.Furthermore, the potential of improvements is shown by simulating different driving manoeuvres with the complete vehicle model by varying some vehicle characteristics such as tyre stiffness, shock absorber characteristics, spring stiffness and unsprung mass.In addition to that, simulations with models of unconventional spring- and damper-systems have been carried out to demonstrate the potential of improvements by the use of these systems. Two different controller algorithms for a semiactive and an active suspension system have been used an will be compared in this paper. 相似文献
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悬架系统的减振器支架作为连接车架及减振器的零件,在车辆运行过程中,因受到减振器的拉力及压力,经常导致断裂失效,致使减振器无法正常工作。文章以某车型减振器支架的故障断裂为例,采用HyperMesh有限元分析方法对支架进行应力分析,计算结果表明:支架最大应力384MPa,应力最大位置与故障件断裂位置吻合,因此,判断支架因强度不足导致的断裂。针对支架的断裂原因,提出了3种加强改进方案,从应力、重量、成本、整改周期等因素考虑,选择最优的改进方案。整改后的减振器支架3年内售后故障率为0,达到预期效果,整改方案有效。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):463-480
The linear quarter car model is the most widely used suspension system model. A number of authors expressed doubts about the accuracy of the linear quarter car model in predicting the movement of a complex nonlinear suspension system. In this investigation, a quarter car rig, designed to mimic the popular MacPherson strut suspension system, is subject to narrowband excitation at a range of frequencies using a motor driven cam. Linear and nonlinear quarter car simulations of the rig are developed. Both isolated and operational testing techniques are used to characterise the individual suspension system components. Simulations carried out using the linear and nonlinear models are compared to measured data from the suspension test rig at selected excitation frequencies. Results show that the linear quarter car model provides a reasonable approximation of unsprung mass acceleration but significantly overpredicts sprung mass acceleration magnitude. The nonlinear simulation, featuring a trilinear shock absorber model and nonlinear tyre, produces results which are significantly more accurate than linear simulation results. The effect of tyre damping on the nonlinear model is also investigated for narrowband excitation. It is found to reduce the magnitude of unsprung mass acceleration peaks and contribute to an overall improvement in simulation accuracy. 相似文献
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