Semi-active H∞ control of high-speed railway vehicle suspension with magnetorheological dampers

In this paper, semi-active H∞ control with magnetorheological (MR) dampers for railway vehicle suspension systems to improve the lateral ride quality is investigated. The proposed semi-active controller is composed of a H∞ controller as the system controller and an adaptive neuro-fuzzy inference system (ANFIS) inverse MR damper model as the damper controller. First, a 17-degree-of-freedom model for a full-scale railway vehicle is developed and the random track irregularities are modelled. Then a modified Bouc–Wen model is built to characterise the forward dynamic characteristics of the MR damper and an inverse MR damper model is built with the ANFIS technique. Furthermore, a H∞ controller composed of a yaw motion controller and a rolling pendulum motion (lateral motion+roll motion) controller is established. By integrating the H∞ controller with the ANFIS inverse model, a semi-active H∞ controller for the railway vehicle is finally proposed. Simulation results indicate that the proposed semi-active suspension system possesses better attenuation ability for the vibrations of the car body than the passive suspension system.     

Generalized magnetorheological (MR) damper model and its application in semi-active control of vehicle suspension system

In this paper, analytical characterization of the magneto-rheological (MR) damper is done using a new modified algebraic model. Algebraic model is also more preferable because of its low computational expenses compared to differential Bouc-Wen’s model which is highly computationally demanding. This model along with the obtained model parameters is used as a semi-active suspension device in a quarter car model and the stationary response of the vehicle traversing on a rough road is obtained. The control part consists of two nested controllers. One of them is the system controller which generates the desired damping force and the other is the damper controller which adjusts the voltage level to MR damper so as to track the desired damping force. For the system controller a model reference skyhook Sliding Mode Controller (SMC) is used and for the damper controller a continuous state algorithm is built to determine the input voltage so as to gain the desired damping force. The analytical model is subsequently used in the quarter car vehicle model and the vehicular responses are studied. A simulation study is performed to prove the effectiveness and robustness of the semi-active control approach. Results show that the semi-active controller can achieve compatible performance as that of active suspension controller except for a little deterioration.     

Decentralized neuro-fuzzy control for half car with semi-active suspension system

In this paper, a decentralized neuro-fuzzy controller has been created in order to improve the ride comfort and increase the stability for half car suspension system, which used the magneto-rheological damper as a semi-active device. Firstly, relative gain array and relative disturbance gain methods have been used for deriving a relation between inputs, disturbances and outputs to select pairing with minimum interaction to design a decentralize controller. Secondary, decentralized neuro-fuzzy controllers for front and rear chassis are designed to predict the required damping force taking the acceleration of the sprung mass and desired acceleration obtained by using pole-placement method as inputs. To predict the control voltage required for producing the force predicted by the controller, the inverse neuro-fuzzy model of MR damper has been designed. Simulation by using MATLAB programs has been created. The results show that the ride comforts and vehicle stability have been improved in comparison with the passive system.     

一种用于车辆半主动悬架控制的磁流变阻尼器模型

文中对适用于车辆半主动悬架控制器设计的磁流变阻尼器模型进行研究.首先分析阻尼力与位移、速度以及输入电流之间的关系,并结合现有阻尼器模型的优点,提出一种精确的便于控制的双曲正切磁滞模型.接着,将磁流变阻尼器安装在硬件在环仿真平台上进行试验,利用试验得到的阻尼器动态特性数据,进行阻尼器模型的参数辨识和曲线拟合.最后,将基于拟合参数的模型仿真结果与试验数据进行比较,验证了模型的正确性.     

Semi-active suspension systems for railway vehicles using magnetorheological dampers. Part I: system integration and modelling

In this paper, it is aimed to investigate semi-active suspension systems using magnetorheological (MR) fluid dampers for improving the ride quality of railway vehicles. A 17-degree-of-freedom (DOF) model of a full-scale railway vehicle integrated with the semi-active controlled MR fluid dampers in its secondary suspension system is proposed to cope with the lateral, yaw, and roll motions of the car body, trucks, and wheelsets. The governing equations combining the dynamics of the railway vehicle integrated with MR dampers in the suspension system and the dynamics of the rail track irregularities are developed and a linear quadratic Gaussian (LQG) control law using the acceleration feedback is adopted, in which the state variables are estimated from the measurable accelerations with a Kalman estimator. In order to evaluate the performances of the semi-active suspension systems based on MR dampers for railway vehicles, the random and periodical track irregularities are modelled with a uniform state-space formulation according to the testing data and incorporated into the governing equation of the railway vehicle integrated with the semi-active suspension system. Utilising the governing equations and the semi-active controller developed in this paper, the simulation and analysis are presented in Part II of this paper.     

基于ILMI算法的车辆半主动悬架静态输出反馈控制

针对采用磁流变阻尼器的1/4汽车半主动悬架模型进行振动控制分析。利用迭代线性矩阵不等式(ILMI)算法在输出反馈控制中的求解优势,提出基于ILMI算法的半主动悬架静态输出反馈控制方法。仿真结果表明,结合合适的控制算法,采用磁流变阻尼器的半主动悬架系统有效地改善了汽车驾驶平顺性和乘坐舒适性。     

汽车磁流变半主动悬架的控制研究

为了改善汽车的乘坐舒适性和行驶安全性,提出了一种汽车磁流变半主动悬架的控制策略。首先,设计了磁流变减振器的工作模式,通过试验获得了其速度特性和力学特性,建立了磁流变减振器的数学模型;其次,建立了带磁流变减振器的二自由度车辆简化模型及其参数表;最后,基于双环控制理论,设计了一种控制系统,其外环产生理想的结构阻尼力,内环调节电流驱动器的电流,以使磁流变减振器实时地产生控制阻尼力。仿真结果表明:以磁流变减振器为基础,通过半主动控制技术,悬架系统的振动动态性能得到了有效的控制。     

斜拉桥拉索的MR半主动控制研究

根据LQR最优控制理论,结合面向速度剪切(Clipped Optimal)控制算法及修正的磁流变(MR)阻尼器Bouc Wen模型,提出了LQR Clipped半主动控制算法,应用拉索振动的差分离散模型,对斜拉索的面内振动进行了被动、主动及半主动控制研究,分析了MR阻尼器对斜拉索的振动控制效果。研究结果表明:MR阻尼器被动控制能够提供的模态阻尼比可以达到最优油阻尼器控制的值,但MR被动控制存在一个最优输入电压,最优电压值与需控制的第几阶模态有关;与油阻尼器被动控制相比,MR半主动控制可以有效地提高模态阻尼比,尤其在阻尼器位置距索端很近时仍有较好的控制效果。     

汽车半主动悬架的模型参考自适应控制

在1／4车辆动力学模型的基础上，基于李雅普诺夫稳定性理论，以天棚阻尼半主动悬架为参考模型，设计了半主动悬架模型参考自适应控制器。自适应控制器包括可调前置控制器和状态反馈控制器两个部分。推导了自适应控制律与相应的约束条件。仿真结果表明：该控制器对于模型参数的不确定性具有良好的鲁棒特性。自适应控制器不仅明显降低了车身加速度，提高了平顺性，同时也使汽车的行驶安全性获得了改善，悬架动变形稍有增大。     

基于半主动自适应悬架系统的整车道路友好性研究

为了提高车辆的道路友好性与平顺性,设计了以磁流变减振器为控制对象的整车自适应模糊控制半主动悬架系统。在试验测试和理论分析的基础上,建立了基于磁流变减振器的整车半主动悬架模型及其状态方程,并用该模型对自适应模糊控制方法进行了研究。模型的输入采用B级和C级路面谱;道路友好性评价指标采用动载荷系数和动载荷应力因子;使用MATLAB/Simulink建立基于2个自适应模块的模糊控制器控制系统,模糊控制器的输入均采用车身与车桥的相对速度和相对加速度。仿真结果表明:与被动悬架相比,在B级和C级路面、不同速度下,半主动自适应悬架动载荷系数均降低30%左右,动载荷应力因子均降低40%以上,同时也提高了车辆的运行平顺性和稳定性。     

应用于汽车减振的磁流变液阻尼器的设计原理

应用智能材料磁流变液（MR）构造出的半主动悬架减振系统，可以用于对车辆振动的控制。MR流体具有的独特性质在于：在强磁场的作用下，可由牛顿流体变为粘塑流体，而变液阻尼器则具有结构简单、体积小、工作连续可逆，能耗小等优点。本文介绍了磁流变液的材料特性，建立了磁流变液阻尼器的阻尼力数学模型，并提出设计变阻尼器时参数的选取原则。     

Hardware-in-the-loop simulation experiment for semi-active vibration control of lateral vibrations of railway vehicle by magneto-rheological fluid damper

The active lateral suspension (ALS) of a train consists of either active or semi-active technologies. However, such an active system on a real railway vehicle is not easy to test because of cost and time. In this study, a hardware-in-the-loop simulation (HILS) system is developed to test the ALS. To this end, the dynamic model of a railway vehicle is equipped with the actuator, two bogies and four-wheel sets, and the ALS is used. The proposed HILS system consists of an alternating current servo motor connected to a ball-screw mechanism and a digital control system. The digital control system implements the dynamic model and the control algorithm. The design and manufacture of the HILS system are explained in detail. Both the passive damper and the magneto-rheological (MR) fluid damper are tested using the HILS system, where the sky-hook control algorithm was applied for the MR fluid damper. Experimental results show that the proposed HILS system can be effectively used for the performance estimation of the ALS.     

半主动悬架的滑模变结构控制

针对带有电流变液智能阻尼器的半主动汽车悬架模型,运用滑模变结构方法设计了半主动悬架滑模控制器。根据滑模运动方程稳定的Hurwitz判据选择滑模面系数,用指数趋近率改善滑模运动段的动态品质并进一步确定了半主动悬架的实时控制阻尼力。对多种激励信号下隔振质量的响应及半主动悬架系统在系统参数摄动下的鲁棒特性进行了仿真分析。结果表明:变结构控制下半主动悬架系统的隔振效果要远好于最优被动系统,而且对外界扰动有一定的适应性,对系统参数摄动也具有很强的鲁棒性。     

基于磁流变阻尼器的半主动车辆座椅悬架模糊控制研究

设计基于磁流变阻尼器的半主动车辆座椅悬架系统的模糊控制器。用ADAMS对系统建立三维多刚体动力学模型,用MATLAB设计系统模糊控制器,并联合两者对整个系统进行仿真。仿真和台架试验结果表明,模糊控制策略能使该系统较好抑制垂直振动加速度,提高乘坐的舒适性。     

Skyhook and H8 Control of Semi-active Suspensions: Some Practical Aspects

Summary This paper deals with single-wheel suspension car model. We aim to prove the benefits of controlled semi-active suspensions compared to passive ones. The contribution relies on H 8 control design to improve comfort and road holding of the car under industrial specifications, and on control validation through simulation on an exact nonlinear model of the suspension. Note that we define semi-active suspensions as control systems incorporating a parallel spring and an electronically controlled damper. However, the type of damper used in automotive industry can only dissipate energy. No additional force can be generated using external energy. The control issue is then to change, in an accurate way, the damping (friction) coefficient in real-time. This is what we call semi-active suspension. For this purpose, two control methodologies, H 8 and Skyhook control approaches, are developed, using a linear model of the suspension, and compared in terms of performances using industrial specifications. The performance analysis is done using the control-oriented linear model first, and then using an exact nonlinear model of the suspension incorporating the nonlinear characteristics of the suspension spring and damper.     

Skyhook and H8 Control of Semi-active Suspensions: Some Practical Aspects

Summary This paper deals with single-wheel suspension car model. We aim to prove the benefits of controlled semi-active suspensions compared to passive ones. The contribution relies on H 8 control design to improve comfort and road holding of the car under industrial specifications, and on control validation through simulation on an exact nonlinear model of the suspension. Note that we define semi-active suspensions as control systems incorporating a parallel spring and an electronically controlled damper. However, the type of damper used in automotive industry can only dissipate energy. No additional force can be generated using external energy. The control issue is then to change, in an accurate way, the damping (friction) coefficient in real-time. This is what we call semi-active suspension. For this purpose, two control methodologies, H 8 and Skyhook control approaches, are developed, using a linear model of the suspension, and compared in terms of performances using industrial specifications. The performance analysis is done using the control-oriented linear model first, and then using an exact nonlinear model of the suspension incorporating the nonlinear characteristics of the suspension spring and damper.     

An Experimental Investigation of Preview Control

There is mounting theoretical evidence to suggest that preview control can be of substantial benefit to a semi-active suspension for random road inputs. In this paper, the benefits of wheel-base preview control are measured experimentally, using a prototype semi-active damper in a half-car ‘Hardware-in-the-loop’ (HiL) rig with a planar two-axle heavy vehicle model. The benefits of preview control using the prototype semi-active damper are found to be less than theoretically possible, due to the phase lag between the demanded and achieved damping force. It is shown that the performance of the prototype damper can be improved significantly by having a theoretical simulation running ahead of the HiL vehicle. The theoretical simulation is used to predict the demanded damper force for the HiL vehicle, and thereby compensate for the phase lag in the prototype damper.     

An Experimental Investigation of Preview Control

There is mounting theoretical evidence to suggest that preview control can be of substantial benefit to a semi-active suspension for random road inputs. In this paper, the benefits of wheel-base preview control are measured experimentally, using a prototype semi-active damper in a half-car 'Hardware-in-the-loop' (HiL) rig with a planar two-axle heavy vehicle model. The benefits of preview control using the prototype semi-active damper are found to be less than theoretically possible, due to the phase lag between the demanded and achieved damping force. It is shown that the performance of the prototype damper can be improved significantly by having a theoretical simulation running ahead of the HiL vehicle. The theoretical simulation is used to predict the demanded damper force for the HiL vehicle, and thereby compensate for the phase lag in the prototype damper.     

基于磁流变阻尼器的发动机振动模糊PID控制

在对发动机激振力及动力学模型分析的基础上,提出一种模糊PID控制方法,设计出了基于磁流变阻尼器的发动机振动控制的半主动模糊PID控制器,并运用MATLAB/Simulink对隔振控制系统进行了对比仿真.仿真结果显示,与橡胶隔振垫和PID控制相比,采用模糊PID控制的磁流变阻尼器的发动机有更明显的隔振效果,表明了磁流变阻尼器在汽车发动机上运用的可行性.     

电流变智能半主动悬架模糊PID控制

对带有电流变液智能阻尼器的半主动汽车悬架系统设计了一种模糊PID控制器。将半主动悬架簧载质量的位移及其导数作为模糊控制器的输入，PID控制器的3个增益参数作为其输出，利用电流变液智能阻尼器的阻尼力可随电压变化的特性来使车身的振动降为最小。仿真实验给出了最优被动悬架、固定参数PID控制智能半主动悬架和模糊PID控制智能半主动悬架在不同路面激励情况下的响应曲线。