Technical Note: Force Control in Electrohydraulic Active Suspensions Revisited

The inner loop control for the actuator force can be quite simply compensated by means of a correction term to the desired force signal at the input. The correction requires only a measurement of the actuator piston velocity and is employed to cancel the loop disturbance caused by the oil flow to the actuator. Although an additional time constant is introduced by the integration in the inner loop force control, the overall performance is nevertheless quite close to that of an ideal optimal system.     

Technical Note: Force Control in Electrohydraulic Active Suspensions Revisited

The inner loop control for the actuator force can be quite simply compensated by means of a correction term to the desired force signal at the input. The correction requires only a measurement of the actuator piston velocity and is employed to cancel the loop disturbance caused by the oil flow to the actuator. Although an additional time constant is introduced by the integration in the inner loop force control, the overall performance is nevertheless quite close to that of an ideal optimal system.     

Properties of Air Spring as a Force Generator in Active Vibration Control Systems

In the active vibration control systems of electropneumatic type the air spring is often used not only as the elastic element of the system, but also as the compensation force generator, which caters for improved vibro-isolating effects. To provide this function of the air spring, it is necessary to know its characteristics in sufficient detail. In this paper the procedure of experimental estimation of these characteristics is described and the result is compared with the results of estimation based on theoretical considerations. The paper is completed by the graph of both types of characteristics.     

Properties of Air Spring as a Force Generator in Active Vibration Control Systems

In the active vibration control systems of electropneumatic type the air spring is often used not only as the elastic element of the system, but also as the compensation force generator, which caters for improved vibro-isolating effects. To provide this function of the air spring, it is necessary to know its characteristics in sufficient detail. In this paper the procedure of experimental estimation of these characteristics is described and the result is compared with the results of estimation based on theoretical considerations. The paper is completed by the graph of both types of characteristics.     

基于横摆率跟踪的主动悬架前后轴控制力匹配

研究了轮胎的非线性特性、侧向力与垂直载荷耦合特性对车辆操纵稳定性的影响,发现当侧向加速度较大时,4WS对横摆率的控制作用急剧减弱,而通过主动悬架的控制能有效提高横摆率的响应.提出了基于横摆率跟踪控制的4WS和主动悬架的协调控制方法,对前后轴主动悬架控制力进行了分配,提高了大侧向加速度时的横摆率响应.转向盘角阶跃输入的仿真分析表明,该方法可获得优于4WS和主动悬架简单叠加时的综合性能.     

基于AMESim的搅拌运输车电液控制系统仿真

对电控混凝土搅拌运输车的液压系统进行了建模和仿真,建立了电控混凝土搅拌运输车的电液控制系统的传递函数。在此基础上,利用AMESim软件对电液控制系统进行仿真分析,并分别在进料工况、正常工况和改变斜盘角度三种工况下,对系统的仿真模型进行了验证。     

一种后支撑桥提升的电动液压控制系统的设计

随着汽车电子控制技术和液压控制技术的迅猛发展,一种后支撑桥提升的电动液压控制装置应运而生,此方法操纵控制简便,自动化程度高。     

Technical Note: RMS Values for Control Force,Suspension Stroke and Tyre Deflection in an Active Suspension

Expressions are derived for the numerical computation of rms values for control force, suspension stroke and dynamic tyre deflection in a quarter-car vehicle model on a random road of given roughness. A quadratic performance index is employed and the effects of the assumed weighting factors on the rms values and overall static stiffness determined.     

Technical Note: RMS Values for Control Force, Suspension Stroke and Tyre Deflection in an Active Suspension

Expressions are derived for the numerical computation of rms values for control force, suspension stroke and dynamic tyre deflection in a quarter-car vehicle model on a random road of given roughness. A quadratic performance index is employed and the effects of the assumed weighting factors on the rms values and overall static stiffness determined.     

自抗扰控制在前轮主动转向控制中的应用

为进一步提高前轮主动转向的性能,采用自抗扰控制算法来实现前轮主动转向控制.在对车辆动力学方程进行规范化的基础上,设计了二阶自抗扰控制算法.在双移线工况和对开路面加速工况下,对该算法的控制效果进行了硬件在环的仿真试验研究.结果表明,自抗扰控制算法能够有效地实现前轮主动转向控制,控制效果优于P1D控制,具有更高的抗扰动能力...     

客运专线架桥机电液控制系统的设计

0引言 根据中国铁路跨越式发展的需要,铁路客运专线的建设已全面展开,其建设和发展体现了一个国家的技术水平和经济实力。纵观世界已建、在建的高速铁路和中国目前已建、在建的客运专线,采用高架桥的线路里程一般占线路总长的一半或更多。     

边坡稳定性分析中水作用力计算方法研究

水作用力计算的正确与否对边坡稳定性分析结果有着重大影响,然而当前计算水作用力的方法有缺陷。文中在力的正确选取的前提下确定了两类水作用力的计算模型,在此基础上对现有常用方法进行了合理性分析。提出了边坡稳定性分析中单个条块的地下水流网形态,导出了新的水作用力计算方法。     

基于等效力的汽车主动避撞模型及其仿真

为使汽车主动避撞模型能够在人-车-路不同行车环境下保证汽车的主动避撞效果,建立了基于等效力的汽车主动避撞模型.通过以汽车风险评估中提出的等效力模型为基础,加入路面附着系数因子、驾驶员激进程度因子和汽车速度因子,得到行车等效力模型,通过实际行车等效力与不同行车环境中的标准等效力进行对比,实现汽车主动避撞预警.利用Simu...     

Force Control of a Semi-Active Damper

SUMMARY

Two strategies are investigated for controlling a semi-active damper to track a prescribed force demand signal: (i) ‘open loop’ control, using a model of the damping force versus velocity characteristics; and (ii) force feedback (closed loop) control.

The damping characteristics and switching transients of a prototype damper were measured, and used to develop a mathematical model of the dynamics of the damper. The two control strategies were investigated using an idealised (constant velocity) test. Their performance was also simulated and measured under realistic operating conditions using the Hardware-in-the-Loop testing method.

Open loop damper control was generally found to give superior performance to force feedback control, due to its smaller phase lag at high frequencies.     

Force Control of a Semi-Active Damper

Two strategies are investigated for controlling a semi-active damper to track a prescribed force demand signal: (i) 'open loop' control, using a model of the damping force versus velocity characteristics; and (ii) force feedback (closed loop) control.

The damping characteristics and switching transients of a prototype damper were measured, and used to develop a mathematical model of the dynamics of the damper. The two control strategies were investigated using an idealised (constant velocity) test. Their performance was also simulated and measured under realistic operating conditions using the Hardware-in-the-Loop testing method.

Open loop damper control was generally found to give superior performance to force feedback control, due to its smaller phase lag at high frequencies.     

轮毂电机驱动车辆驱动力控制研究

轮毂电机驱动车辆各轮转矩精确可控且响应迅速的特点适用于越野工况,但越野路面起伏不一且附着条件多变,因此,开发基于越野工况辨识的车辆驱动力控制策略,对提升轮毂电机驱动车辆的纵向行驶稳定性具有重要意义。基于动力学模型分析路面附着与路面几何特征,确定可用于越野工况辨识的车辆特征参数集;针对车轮悬空垂向载荷估计失真现象,且由于地面垂向力的实际变化导致车辆垂向载荷分配比例的改变,修正了垂向载荷的计算;利用各特征参数的差异与越野工况的映射关系判定工况属性,采用模糊识别法界定4种地形工况;驱动力控制上层考虑工况与驾驶员影响因素,通过越野工况辨识结果决策驱动利用系数,作为前馈期望转矩调节权重;中层通过四轮垂向载荷得到转矩分配系数,设计驱动力分配算法;下层针对车辆在越野工况下出现车轮滑转与悬空状态,对车轮进行动态转矩补偿。仿真测试与实车验证表明,越野工况辨识结果与预期相符,驱动力控制策略综合优化了车辆稳定性和动力性。     

规则自调整模糊控制及其在主动悬架系统中的应用

根据路面 车辆系统的非线性特点,本文提出一种在线可调整的模糊控制算法,其模糊控制规则表可以用解析的方法进行计算。该方法不仅体现了模糊控制算法对非线性系统具有的明显优势,而且利用LMS自适应算法在线调整模糊控制器的修正因子。针对简化的车辆模型,以路面信号作为激励源进行了仿真研究,证明该算法对悬架系统的振动控制具有较好的效果,簧上质量加速度功率谱密度得到明显降低。     

电液主动悬架的自校正控制

运用衰减记忆递推最小二乘参数估计算法和广义加权最小方差自校正控制算法对主动悬架系统进行控制，并利用压力伺服阀控制的液压缸作为执行器。理论分析和仿真结果表明，所提出的控制系统是可行的，这种自适应自校正算法对系统中一些时变参数具有良好的适应性。     

主动汽车悬架的非线性控制

本文采用１／４车模型对天棚阻尼器和主动悬架的动力学性能进行分析，针对执行器的非线性特性，探讨了微分几何法和反馈法线必互法在主动悬架控制中的应用，在系统控制设计中采用了离散滑模法，仿真结果显示非线性控制律能有效地改善主动悬架的隔振特性。     

Active Roll Control of Articulated Vehicles

This paper describes an investigation into active roll control of articulated vehicles. The objective is to minimise lateral load transfer using anti-roll bars incorporating low bandwidth hydraulic actuators. Results from handling tests performed on an articulated vehicle are used to validate a nonlinear yaw/roll model of the vehicle. The methodology used to design lateral acceleration controllers for vehicles equipped with active anti-roll bars is developed using a simplified linear articulated vehicle model. The hardware limitations and power consumption requirements of the active elements are studied. The controller is then implemented in the validated articulated vehicle model to evaluate the performance of an articulated lorry with active anti-roll bars. The simulation results demonstrate the possibility of a significant improvement in transient roll performance of the vehicle, using a relatively low power system (10 kW), with low bandwidth actuators (5 Hz).