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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):361-386
Passive fluidically coupled suspensions have been considered to offer a promising alternative solution to the challenging design of a vehicle suspension system. A theoretical foundation, however, has not been established for fluidically coupled suspension to facilitate its broad applications to various vehicles. The first part of this study investigates the fundamental issues related to feasibility and properties of the passive, full-vehicle interconnected, hydro-pneumatic suspension configurations using both analytical and simulation techniques. Layouts of various interconnected suspension configurations are illustrated based on two novel hydro-pneumatic suspension strut designs, both of which provide a compact design with a considerably large effective working area. A simplified measure, vehicle property index, is proposed to permit a preliminary evaluation of different interconnected suspension configurations using qualitative scaling of the bounce-, roll-, pitch- and warp-mode stiffness properties. Analytical formulations for the properties of unconnected and three selected X-coupled suspension configurations are derived, and simulation results are obtained to illustrate their relative stiffness and damping properties in the bounce, roll, pitch and warp modes. The superior design flexibility feature of the interconnected hydro-pneumatic suspension is also discussed through sensitivity analysis of a design parameter, namely the annular piston area of the strut. The results demonstrate that a full-vehicle interconnected hydro-pneumatic suspension could provide enhanced roll- and pitch-mode stiffness and damping, while retaining the soft bounce- and warp-mode properties. Such an interconnected suspension thus offers considerable potential in realising enhanced decoupling among the different suspension modes. 相似文献
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In this research, the concept of the kinematic roll center is reviewed from the viewpoint of three-dimensional spatial kinematics.
The theory of screws, which is widely used in spatial kinematics and robotics, is used to prove the validity of the conventional
planar methods for finding the roll center in an initial symmetric vehicle position. The kinematic roll axis, which is referred
to as the roll twist axis in this paper, is defined as the instantaneous screw axis of the vehicle body in roll motion with
respect to the ground, and a three-dimensional method to determine the roll twist axis of a full-vehicle model in an initial
symmetric position is introduced. The proposed method is based on screw theory, which relates the kinematics of a full-vehicle
model to the statics of the full-vehicle model using the concepts of screws, twists, wrenches, the rate of working, and the
reciprocity of screws. The results of the proposed three-dimensional method are compared with those of the conventional planar
methods, and it is found that the conventional methods are valid under the assumption that the vehicle is in a symmetric situation. 相似文献
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SUMMARY Active control of non-stationary response of a single degree of freedom vehicle model with nonlinear passive suspension elements is considered in this paper. The method of equivalent linearization is used to derive the equivalent linear model and the optimal control laws are obtained by using stochastic optimal control theory based on full state information. Velocity squared quadratic damping and hysteresis type of stiffness nonlinearities are considered. The effect of the nonlinearities on the active system performance is studied. The performance of active suspensions with nonlinear passive elements is found to be superior to the corresponding passive suspension systems. 相似文献
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在考虑摩擦、马达阻尼力以及流动压力损失的影响下,研究非线性对液压式惯容器-弹簧-阻尼(ISD)悬架性能的影响。文章建立了两级串联式非线性液压ISD悬架的整车模型,分析了飞轮转动惯量、马达排量、油液实际作用面积以及回流管等效长度这四个非线性参数对液压ISD悬架性能的影响,在仿真的基础上,进行了液压ISD悬架的整车台架试验研究,验证了非线性模型的正确性。研究结果可建立精确的非线性液压ISD悬架系统模型,为进一步提高主动、半主动ISD悬架的控制的有效性提供了支撑。 相似文献
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非线性液压阻尼悬架的优化设计及最优控制 总被引:7,自引:1,他引:7
本文对二自由度非线液压阻尼悬架系统进行了统计线性分析,并提出这种半主动非线性液压阻尼悬架系统针对不同路况进行最优控制的控制策略;同时对非线性阻尼系统进行实时仿真,得出此类液压阻尼对振动的抑制优于线性阻尼的结论。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(12):1830-1849
In this paper, a roll and pitch independently tuned hydraulically interconnected passive suspension is presented. Due to decoupling of vibration modes and the improved lateral and longitudinal stability, the stiffness of individual suspension spring can be reduced for improving ride comfort and road grip. A generalised 14 degree-of-freedom nonlinear vehicle model with anti-roll bars is established to investigate the vehicle ride and handling dynamic responses. The nonlinear fluidic model of the hydraulically interconnected suspension is developed and integrated with the full vehicle model to investigate the anti-roll and anti-pitch characteristics. Time domain analysis of the vehicle model with the proposed suspension is conducted under different road excitations and steering/braking manoeuvres. The dynamic responses are compared with conventional suspensions to demonstrate the potential of enhanced ride and handling performance. The results illustrate the model-decoupling property of the hydraulically interconnected system. The anti-roll and anti-pitch performance could be tuned independently by the interconnected systems. With the improved anti-roll and anti-pitch characteristics, the bounce stiffness and ride damping can be optimised for better ride comfort and tyre grip. 相似文献
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运用虚功原理导出了悬架受力、弹簧刚度与悬架刚度之间、阻尼器参数与系统阻尼之间的非线性函数关系。开发了简单实用的双横臂-螺旋弹簧独立悬架仿真分析与设计软件,应用于某微型电动汽车的悬架系统设计。利用ADAMS建立双横臂悬架模型,通过仿真验证了公式及其结论的正确性。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):341-360
Summary This paper presents an investigation of the feedback control performance of a full-vehicle suspension system featuring magnetorheological (MR) dampers. A cylindrical MR damper is designed and manufactured by incorporating a Bingham model of aMR fluid which is commercially available. After evaluating the field-dependent damping characteristics of the MR damper, a full-vehicle suspension system installed with 4 independent MR dampers is constructed and its governing equations of motion which include vertical, pitch and roll motions are derived. A H 8 controller which has inherent robustness against system uncertainties is formulated by treating the sprung mass of the vehicle as uncertain parameter. This is accomplished by adopting the loop shaping design procedure. For the demonstration of a practical feasibility, control performance characteristics for vibration suppression of the proposed MR suspension system are evaluated under various road conditions through the hardware-in-the-loop simulation (HILS) methodology. 相似文献
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Seung-Bok Choi Hwan-Soo Lee Young-Pil Park 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2002,38(5):341-360
Summary This paper presents an investigation of the feedback control performance of a full-vehicle suspension system featuring magnetorheological (MR) dampers. A cylindrical MR damper is designed and manufactured by incorporating a Bingham model of aMR fluid which is commercially available. After evaluating the field-dependent damping characteristics of the MR damper, a full-vehicle suspension system installed with 4 independent MR dampers is constructed and its governing equations of motion which include vertical, pitch and roll motions are derived. A H 8 controller which has inherent robustness against system uncertainties is formulated by treating the sprung mass of the vehicle as uncertain parameter. This is accomplished by adopting the loop shaping design procedure. For the demonstration of a practical feasibility, control performance characteristics for vibration suppression of the proposed MR suspension system are evaluated under various road conditions through the hardware-in-the-loop simulation (HILS) methodology. 相似文献
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针对国产某微型轿车,在建立汽车悬架系统5自由度模型和时域路面模型基础上,对悬架系统的线性弹簧和非线性阻尼参数进行了优化。根据优化结果,对悬架系统的刚度和阻尼进行了匹配设计。经试验表明:座椅加速度自谱峰值减小7.4%,加速度均方根值减小19.4%,有效地改善了该车的行驶平顺性,证明时域优化方法对于悬架系统非线性参数优化是可行的。 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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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1186-1199
Electromechanical vehicle suspension systems represent a promising substitute to conventional hydraulic solutions. However, the design of electromechanical devices that are able to supply high damping forces without exceeding geometric dimension and mass constraints is a difficult task. All these challenges meet in off-road vehicle suspension systems, where the power density of the dampers is a crucial parameter. In this context, the present paper outlines a particular shock absorber configuration where a suitable electric machine and a transmission mechanism are utilised to meet off-road vehicle requirements. A dynamic model is used to represent the device. Subsequently, experimental tests are performed on an actual prototype to verify the functionality of the damper and validate the proposed model. 相似文献
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Mohammad Hasan Shojaeefard Sadegh Yarmohammadisatri 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(6):827-852
The main purpose of this paper is to propose a new method for designing Macpherson suspension, based on the Sobol indices in terms of Pearson correlation which determines the importance of each member on the behaviour of vehicle suspension. The formulation of dynamic analysis of Macpherson suspension system is developed using the suspension members as the modified links in order to achieve the desired kinematic behaviour. The mechanical system is replaced with an equivalent constrained links and then kinematic laws are utilised to obtain a new modified geometry of Macpherson suspension. The equivalent mechanism of Macpherson suspension increased the speed of analysis and reduced its complexity. The ADAMS/CAR software is utilised to simulate a full vehicle, Renault Logan car, in order to analyse the accuracy of modified geometry model. An experimental 4-poster test rig is considered for validating both ADAMS/CAR simulation and analytical geometry model. Pearson correlation coefficient is applied to analyse the sensitivity of each suspension member according to vehicle objective functions such as sprung mass acceleration, etc. Besides this matter, the estimation of Pearson correlation coefficient between variables is analysed in this method. It is understood that the Pearson correlation coefficient is an efficient method for analysing the vehicle suspension which leads to a better design of Macpherson suspension system. 相似文献
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本文在理论上建立了一套基于主动力反馈原理的新型主动阻尼悬架的设计和优化方法。首先提出了该主动阻尼悬架的实现模型,该模型是在传统的液力减振器的基础上,应用半主动控制的思想,结合力反馈的原理建立起来的内部液压反馈阻尼网络模型。理论优化分析和计算机仿真表明,通过该液阻网络模型,即可以实现电控的主动阻尼悬架的功能,它可以根据汽车行驶路况的好坏,自适应地调节悬架阻尼大小以实现主动阻尼悬架的最优控制。 相似文献
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S. NARAYANAN Professor G.V. Raju 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1992,21(1):73-87
Active control of non-stationary response of a single degree of freedom vehicle model with nonlinear passive suspension elements is considered in this paper. The method of equivalent linearization is used to derive the equivalent linear model and the optimal control laws are obtained by using stochastic optimal control theory based on full state information. Velocity squared quadratic damping and hysteresis type of stiffness nonlinearities are considered. The effect of the nonlinearities on the active system performance is studied. The performance of active suspensions with nonlinear passive elements is found to be superior to the corresponding passive suspension systems. 相似文献