A new controller for the semi-active suspension system with magnetorheological dampers

~~under the sliding mode controller. It shows that the sliding mode controller yield almost perfect tracking to the reference model. It can be seen in Fig.6 that the acceleration of sprung mass under sliding mode controller is controlled within ?.7 m/s2. Fig.7 shows the robustness and stability of the sliding mode controller to the parameter variations of the system to be controlled, in this case, a relative decrease of 10 % in the sprung mass and a relative increase of 15 % in the stiffness o…     

Signal frequency based self-tuning fuzzy controller for semi-active suspension system

A new kind of fuzzy control scheme, based on the identification of the signal's main frequency and the behavior of the ER damper, is proposed to control the semi-active suspension system. This method adjusts the fuzzy controller to achieve the best isolation effect by analyzing the main frequency's characters and inspecting the change of system parameters. The input of the fuzzy controller is the main frequency and the optimal damping ratio is the output. Simulation results indicated that the proposed control method is very effective in isolating the vibration. Project (No. 69974024) supported by the National Natural Science Foundation of China     

Signal frequency based self-tuning fuzzy controller for semi-active suspension system

INTRODUCTIONRoadvehiclesuspensiondesignhasreceivedgreatattentioninrecentyears .Theperformanceofthesuspensionsystemplaysanimportantroleinachievinggoodhandlingandridingcomfort.Practically ,thesimplestandmostcommontypesofsuspensionsarepassiveinthesensethatno…     

A tunable fuzzy logic controller for the vehicle semi-active suspension system

On the basis of analyzing the system constitution of vehicle semi-active suspension,a 4-DOF(degree of freedom)dynamic model is established.A tunable fuzzy logic controller is designed by using without quantification method and taking into account the uncertainty,nonlinearity and complexity of parameters for a vehicle suspension system.Simulation to test the performance of this controller is performed under random excitations and definite disturbances of a C grade road,and the effects of time delay and changes of system parameters on the vehicle suspension system are researched.The numerical simulation shows that the performance of the designed tunable fuzzy logic controller is effective,stable and reliable.     

由MR阻尼器驱动的汽车悬架减振系统的半主动控制研究

设计了一种半主动力跟踪PI控制器，对由磁流液(MR)阻尼器作为悬架阻尼器的汽车模型进行控制分析．MR阻尼器的2种不同模型在闭环的汽车悬架控制系统模型中得到了应用．2种模型是基于均值阻尼力对速度(f-v)特性的均值F-v模型，和描述阻尼力非光滑滞环和饱和特性的滞环f-v模型．汽车模型用来研究力跟踪PI控制算法和MR阻尼器对车辆的振动抑制性能．仿真分析还指出了MR阻尼器的非线性，特别是滞环特性对汽车悬架系统的性能影响．结果表明所提出的控制方法对由MR阻尼器驱动的汽车悬架系统能产生很好的减振效果，不仅体现在对悬架弹簧支撑车厢的共振抑制和对驾乘人员舒适性敏感频域的振动抑制，还体现在对汽车轮胎共振频率周围的振动抑制．结果还进一步说明了MR阻尼器所存在的滞环特性对汽车悬架性能的不良影响．     

A Blast Shock Isolation System with MRFD and Its Semi-Active Control Analysis

To effectively reduce the damage to people and devices in civil defense engineering subjected to blast shock, a blast shock isolation system with magnetorheological fluid dampers （MRFD） is proposed. MRFD can provide continuously adjustable Coulomb friction and has many advantages for semi-active control. Numerical simulation of this isolation system is finished using Matlab simulink toolbox. General semi-active control algorithms are consided based on instantaneous optimal active control algorithm. And the results indicate that the shock isolation system can work efficiently, decreasing about 93% of the peak acceleration of the isolation floor.     

A Blast Shock Isolation System with MRFD and Its Semi-Active Control Analysis

To effectively reduce the damage to people and devices in civil defense engineering subjected to blast shock, a blast shock isolation system with magnetorheological fluid dampers (MRFD) is proposed. MRFD can provide continuously adjustable Coulomb friction and has many advantages for semi-active control. Numerical simulation of this isolation system is finished using Matlab simulink toolbox. General semi-active control algorithms are consided based on instantaneous optimal active control algorithm. And the results indicate that the shock isolation system can work efficiently, decreasing about 93% of the peak acceleration of the isolation floor.     

递归响应法对磁流变阻尼结构的时滞补偿

控制系统中的时滞现象是影响控制效果的不可忽视的因素。文章采用递归响应法对磁流变阻尼控制系统的算法进行仿真计算,分析在不同情况下递归响应法对磁流变阻尼控制系统的时滞补偿效果,并与主动控制系统进行比较。结果表明,递归响应法对磁流变阻尼控制系统有一定的补偿效果,对主动控制系统效果更加显著。     

一种buck型电源变换器的新型滑模控制器设计

结合buck变换器电路的内部关系,从基于电感电流和电容电压的滑模面推导出一种只基于电容电压的新型滑模面,从而省去了对电感电流的测量．从仿真对比结果来看,这种控制可以得到比常规滑模控制更好的动态品质,对负载变化具有更强的鲁棒性．     

Control method for semi-active suspension based on virtual prototype

1 Introduction 1 Semi-active suspension is advantaged by good performance and low price over the passive suspension and active suspension [1]. The control strategy as the core of a control system is widely researched in practice. The simple dynamic model is often adopted in the typical process. However, the differences between the practical and physical models bring on more idealization and less practicability. On the other hand, the mechanical designer and the controls designer use different…     

汽车磁流变半主动悬架的模糊控制

为带有磁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控制器：将半主动悬架相对位移的误差及误差变化率作为模糊控制器的输入,阻尼力作为其输出,利用磁流变液智能阻尼器的阻尼力随电流变化的特性使车身的振动降到最小。仿真实验给出了最优被动悬架和模糊控制智能半主动悬架在随机路面激励情况下的响应曲线,结果表明,磁流变半主动悬架系统采用模糊控制效果较理想,其车身垂直加速度等参数变化幅度也有所降低。     

终端滑模控制器设计在永磁同步电动机中的应用

考虑了一类永磁同步电动机的终端滑模控制器设计问题.在控制器设计中利用中继切换控制使系统在给定的当前控制律的作用下运行到某一特定状态（或某一特定区域）后,控制律被切换到有限时间收敛的终端滑模控制器,使得系统在有限时间内达到平衡状态.终端滑模控制器的设计保证了闭环系统所有信号的有界性和平衡点的全局稳定性,以及系统在有限时间内精确地跟踪给定的参考信号.最后,通过一个数值仿真验证了所提算法的正确有效性.     

A linear rotary magnetorheological damper for vehicles

1.IntroductionOneofthemostimportantperformanceparameterofautomobilesisthecushioningability.Soallkindsofvibrationdampersareassembledinvehicles,amongwhichthefullest-blownoneisthehydraulicdamperworkingthroughreciprocatingmovementofhinderedpistoninahydrauliccylinderabsorbingvibrationwithself-containedspring.Butsuchkindofdampercannotchangewiththechangeincharacteristicsofavibrationsource(suchasamplitudeofvibrationandphase),lackingofenoughself-adaptingability.Magnetorheologicaldamperfluid(MRF)isaty…     

Research on a Rigid Rotor—Sliding Bearing System with a Squeeze Film Damper

In this paper,a dynamic model on a rigid rotor-sliding bearing system with a SFD is established.The stability and bifurcation behaviors of the system are studied,on The basis of the differential equations of fluid momentum and mass continuity,the distribution pressure function is derived by taking oil film inertia force into consideration.Damping force, clearance excitation force,interference force of different frequencies and static load are also considered in the model,Finally,the governing equations of the stability and bifurcation behaviors of the system are solved by Floquet theory,Simulation of dynamic model shows that the rigid rotor-sliding bearing system can maintain stability and exhibit a Hopt bifurcation phenomenon in a certain range.     

PID-based bit allocation strategy for asymmetric stereoscopic video coding with fuzzy quality controller

Asymmetric stereoscopic video coding can take advantage of binocular suppression in human vision by representing one of the two views in lower quality.This paper proposes a bit allocation strategy for asymmetric stereoscopic video coding.In order to improve the accuracy of bit allocation and rate control in the left view,a proportionalintegral-derivative controller is adopted.Meanwhile,to control the quality fluctuation between consecutive frames of the left view,a quality controller is adopted.Besides,a fuzzy controller is proposed to control the variation in quality between the left and right views by comparing the PSNR disparity of two views with a fixed threshold,which is used to quantize the binocular psycho-visual redundancy and adjust the quantization parameter (QP) of the right view correspondingly.The proposed algorithm has been implemented in H.264/AVC video codec,and the experimental results show its effectiveness in rate control while keeping a good quality for the left view,and fewer bits are allocated for the right view so that the overall bit rate is saved by 7.2% at most without the loss of subjective visual quality for stereoscopic video.     

Multi-mode controller IC for soft-switched flyback converter with high efficiency over the entire load range

This paper presents a multi-mode control scheme for a soft-switched flyback converter to achieve high efficiency and excellent load regulation over the entire load range. At heavy load, critical conduction mode with valley switching （CCMVS） is employed to realize soft switching so as to reduce turn-on loss of power switch as well as conducted electromagnetic interference （EMI）. At light load, the converter operates in discontinuous conduction mode （DCM） with valley switching and adaptive off-time control （AOT） to limit the switching frequency range and maintain load regulation. At extremely light load or in standby mode, burst mode operation is adopted to provide low power consumption through reducing both switching frequency and static power dissipation of the controller. The multi-mode control is implemented by an oscillator whose pulse duration is adjusted by output feedback. An accurate valley switching control circuit guarantees the minimum turn-on voltage drop of power switch. The prototype of the controller IC was fabricated in a 1.5-μm BiCMOS process and applied to a 310 V/20 V, 90 W flyback DC/DC converter circuitry. Experimental results showed that all expected functions were realized successfully. The flyback converter achieved a high efficiency of over 80% from full load down to 2.5 W, with the maximum reaching 88.8%, while the total power consumption in standby mode was about 300 mW.     

单片机报时控制器

本介绍了由51系列单片机组成的自动报时控制器的设计方法,给出了相关硬件框图和软件流程图。该控制器是一种比较实用的时间控制装置,可用于各种需要时间控制的场合。     

A study of active suspension based on full DOF vehicle model

1Introduction1Because the traditional suspension can hardly meet the demands for either ride comfort or handling stability when the performance of a vehicle’s light weight and high speed are emphasized,more attention has focused on the development of advanced active suspension and its control method has been researched extensively.The current method for solving the problem of active suspension control for a vehicle often deals with a quarter car or a half car model[1-4].But it is not enough t…     

Pneumatic active suspension system for a one-wheel car model using fuzzy reasoning and a disturbance observer

This paper presents the construction of a pneumatic active suspension system for a one-wheel car model using fuzzy reasoning and a disturbance observer. The one-wheel car model can be approximately described as a nonlinear two degrees of freedom system subject to excitation from a road profile. The active control is composed of fuzzy and disturbance controls, and the active control force is constructed by actuating a pneumatic actuator. A phase lead-lag compensator is inserted to counter the performance degradation due to the delay of the pneumatic actuator. The experimental result indicates that the proposed active suspension improves much the vibration suppression of the car model.     

Multi-objective robust controller synthesis for discrete-time systems with convex polytopic uncertain domain

Multi-objective robust state-feedback controller synthesis problems for linear discrete-time uncertain systems are addressed. Based on parameter-dependent Lyapunov functions, the Gl2 and GH2 norm expressed in terms of LMI (Linear Matrix Inequality) characterizations are further generalized to cope with the robust analysis for convex polytopic uncertain system.Robust state-feedback controller synthesis conditions are also derived for this class of uncertain systems. Using the above results,multi-objective state-feedback controller synthesis procedures which involve the LMI optimization technique are developed and less conservative than the existing one. An illustrative example verified the validity of the approach.