Vibration Performance Analysis of a Mining Vehicle with Bounce and Pitch Tuned Hydraulically Interconnected Suspension

The current investigations primarily focus on using advanced suspensions to overcome the tradeo design of ride comfort and handling performance for mining vehicles. It is generally realized by adjusting spring sti ness or damping parameters through active control methods. However, some drawbacks regarding control complexity and uncertain reliability are inevitable for these advanced suspensions. Herein, a novel passive hydraulically interconnected suspension(HIS) system is proposed to achieve an improved ride-handling compromise of mining vehicles. A lumped-mass vehicle model involved with a mechanical–hydraulic coupled system is developed by applying the free-body diagram method. The transfer matrix method is used to derive the impedance of the hydraulic system, and the impedance is integrated to form the equation of motions for a mechanical–hydraulic coupled system. The modal analysis method is employed to obtain the free vibration transmissibilities and force vibration responses under di erent road excitations. A series of frequency characteristic analyses are presented to evaluate the isolation vibration performance between the mining vehicles with the proposed HIS and the conventional suspension. The analysis results prove that the proposed HIS system can e ectively suppress the pitch motion of sprung mass to guarantee the handling performance, and favorably provide soft bounce sti ness to improve the ride comfort. The distribution of dynamic forces between the front and rear wheels is more reasonable, and the vibration decay rate of sprung mass is increased e ectively. This research proposes a new suspension design method that can achieve the enhanced cooperative control of bounce and pitch motion modes to improve the ride comfort and handling performance of mining vehicles as an e ective passive suspension system.

Control Research of Dual Chamber Hydro-Pneumatic Suspension

Vehicle riding comfort and handling stability are directly affected by suspension performance.A novel dual chamber hydro-pneumatic(DCHP)suspension system is developed in this paper.Based on the structural analysis of the DCHP suspension,an equivalent suspension model is proposed for the control purpose.A cuckoo search(CS)based fuzzy PID controller is proposed for the control of the DCHP suspension system.The proposed controller combines the advantage of fuzzy logic and PID controller,and CS algorithm is used to regulate the membership functions and PID parameters.Compared with tradition LQR controller and passive suspension system,the CSFPID controller can reduce the sprung mass acceleration,and at the same time with no deterioration of tire deflection.

Investigation of Semi-Active Hydro-Pneumatic Suspension for a Heavy Vehicle Based on Electro-Hydraulic Proportional Valve

Hydro-pneumatic suspension is widely used in heavy vehicles due to its nonlinear characteristics of stiffness and damping. However, the conventional passive hydro-pneumatic suspension can’t adjust parameters according to the complicated road environment of heavy vehicles to fulfill the requirements of the vehicle ride comfort. In this paper, a semi-active hydro-pneumatic suspension system based on the electro-hydraulic proportional valve control is proposed, and fuzzy control is used as the control strategy to adjust the?damping force of the semi-active hydro-pneumatic suspension. A 1/4?semi-active hydro-pneumatic suspension model is established, which is co-simulated with AMESim and MATLAB/Simulink. The co-simulation results show that the semi-active hydro-pneumatic suspension system can significantly reduce vibration of the vehicle body, and improve the suspension performance comparing with passive hydro-pneumatic suspension.

Development of a Composite Suspension with a Coil and Hydro-Pneumatic Spring

A new composite suspension is developed, where a coil spring and a hydro-pneumatic spring are used in order to improve the poor reliability of off-road vehicle with pure hydro-pneumatic suspension. According to road conditions, the two springs play different roles. The method for matching the composite suspension stiffness and distributing the load is proposed. The working pressure of hydro-pneumatic spring as well as the load and stiffness characteristics of composite suspension is compared with a pure hydro-pneumatic suspension. In addition, the ISO weighted vehicle body acceleration, suspension travel and relative dynamic load of the wheels between two kinds of suspension are analyzed with a quarter vehicle mode. The simulation result shows that the developed composite suspension is more suitable for off-road vehicle than the one hydro-pneumatic suspension, because the composite suspension can reduce the working pressure, improve the reliability and keep a similar ride comfort with hydro-pneumatic suspension.

Control algorithm for vehicle height adjustable system of hydro-pneumatic suspension based on LuGre model

In order to control the vehicle body position precisely,1/4 nonlinear mathematical model of hydro-pneumatic suspension is established,and the influence of the frictional force in a hydraulic cylinder is analyzed.The friction characteristics are described based on the LuGre model when the piston of a hydraulic actuator is operated at a low speed.Due to the fact parameters of the friction model are effected by the system condition,an adaptive friction compensation（AFC）controller is designed through the Backstepping method,and a dual-observer has been implemented to estimate the friction state.The global asymptotic convergence of a closed-loop system is proven by the Lyapunov theorem.The simulation results show that the positional accuracy of the adaptive friction compensation yiedls a significant improvement in the vehicle height adjustment as compared to the PID control,demonstrating the effectiveness of the adaptive fiction compensation method in the vehicle height adjustable system of the hydro-pneumatic suspension.

Experimental study on wheeled vehicle hydro-pneumatic suspension fault detection

A four-channel MTS road simulation system,which is used to regenerate the acceleration signal at the axle head is presented. A new fault detection method is proposed,which is based on the remote parameter control（ RPC） technology for vehicle hydro-pneumatic suspension system. The transfer function between the drive signals and the axle head acceleration should be identified before the RPC iterative calculation on a computer. By contrasting with the desired frequency response functions（ FRF）,excited through the sample spectrum of road,the iterative convergence speed of the drive function and weighted error are used to detect faults existing in the vehicle＇s suspension. Experimental results show that during the process of regeneration of the acceleration signal at the axle head,the characteristics of failure of the hydro-pneumatic spring are changed randomly resulting in a dramatic increase in calculation of the RPC iterative,which enables relatively large iterative convergence errors. This method can quickly detect and locate a suspension fault and is a simple bench test way in suspension fault detection.

Study on Outboard Inductive Damping Valve in Hydro-pneumatic Suspension

A new outboard inductive damping valve without any electronic control system is developed. Its working principle,structure and external characteristic are studied. Its mathematical model is presented and its damping characteristic is investigated on the basis of fluid continuity equation,differential equations of motion and Bernoulli equation. The influence of the valve parameters on the damping characteristic is studied numerically. The effects of outboard inductive damping valve and common damping valve on ride and tire load are compared also. The external characteristic of the valve is verified in bench test. The results show that the valve’s mathematical model is quite accurate and the developed valve can be adjust in two stages,which can also meet the requirements of the dynamic characteristic of the vehicle suspension system.

Testing Research of Accumulator Performance in the Hydro-pneumatic Suspension of a Vehicle

Taking a 2.5 liter accumulator with hydro-pneumatic suspension in a CXP1032 crane made in Germany as the research object and taking both the overall-road simulative test-bed and the control equipment made by the Schenck Company of Germany as the testing instrument, the structure performance and mechanism are theoretically clarified and the variation of gas states are obtained. This illustrates the accumulating and releasing process of a 2.5 liter accumulator in a 32t crane in the real condition. The preliminary volume and pressure of accumulator would directly affect the stiffness performance of the hydro-pneumatic suspension in a vehicle.

四级阻尼可调式液压互联悬架系统性能研究

提出一种新型四级阻尼可调式液压互联悬架(FDAHIS)系统。FDAHIS系统在被动液压互联悬架系统的阻尼阀上并联了两个常通孔面积不同的电磁开关阀,通过反馈控制策略控制电磁阀开闭状态,调节系统液压流量,从而实现阻尼四级可调。为了研究该系统性能,建立FDAHIS系统模型和七自由度整车模型。通过系统单元台架试验对该模型进行了验证。整车仿真结果表明,与被动的液压互联悬架(HIS)系统相比,FDAHIS系统在车辆行驶平顺性和抗俯仰性能方面表现更佳。

基于模式切换的互联空气悬架性能研究

为进一步提高互联空气悬架性能,设计了一种互联模式切换策略,该策略首先建立互联空气悬架整车动力学模型;然后基于平顺性和操稳性性能指标函数设计综合评价指标,利用不同连通模式下综合指标的变化规律,设计互联模式切换控制策略;最后进行数值仿真,仿真结果表明,该控制策略可明显地改善互联空气悬架性能,提高乘车舒适性。

虚拟轨道列车空气互联平衡悬架的动力学性能研究

针对数字轨道电车前双轴悬架的超静定问题,提出了互联平衡悬架的解决方案。在建立空气弹簧的热力学模型和连接管路热力学模型的基础上,通过与动力学模型联合仿真,验证该优化方案的效果。互联空气悬架可以优化车辆的行驶平顺性,改善车辆动态轴荷分配。分析了互联管路直径对动力学性能的影响。结果表明:该方案改善了数字轨道电车端车的平顺性和载荷均衡性;当连接管路直径取10~20 mm、以车速20 km/h通过减速带的行驶工况下,互联空气平衡悬架的平顺性较原有结构提升了2%~6%,一、二轴的动载荷的峰值相比原有结构降低2%~16%;随着联通管路直径的增加,车辆行驶的平顺性有提高的趋势,一二轴动载荷的平衡效果也越明显;15 mm的管径能较好地平衡减速带和边坡点2种工况下的动力学性能。

基于模糊控制的主动抗侧倾液压互联悬架研究

随着车速提高,车辆侧翻的风险随之增加,因此车辆的抗侧倾性能愈发受到人们的重视。液压互联悬架(HIS)能有效提升车辆的侧倾刚度且几乎不影响车辆的平顺性。根据所研究的主动液压互联悬架,设计了一个以侧倾角和侧倾角加速度作为输入的模糊控制器,直线行驶时控制器几乎不工作,此时车辆等同于被动HIS,两者平顺性近似相同;高速转向时通过控制电机推动调节油缸的活塞杆运动,产生主动的抗侧倾力矩提高车辆的操稳性能。搭建了主动抗侧倾HIS实验台架,通过台架实验验证了主动HIS模型的正确性。对试验车辆底盘进行主动抗侧倾HIS测试系统改装,进行蛇形和双移线试验,并利用MATLAB/Simulink进行相应仿真,比较分析被动HIS车辆和主动HIS车辆的车身侧倾角峰值。结果表明,与被动HIS相比,主动HIS能有效提高车辆的抗侧倾性能。

Development of a Twin-Accumulator Hydro-Pneumatic Suspension

A twin-accumulator hydro-pneumatic suspension has been developed based on the off-road vehicle in order to meet the requirements of ride comfort. The working principle and elements construct of the developed suspension are studied. And then,a mathematical model of the developed suspension is built. The influence of twin-accumulator hydro-pneumatic suspension parameters on the vehicle body vertical acceleration,suspension travel and dynamic tyre load is studied by simulation based on a quarter off-road vehicle model. The ride comfort of the vehicle with the developed suspension is studied by a theoretical evaluation; also the ride comfort of the vehicle with twin-accumulator hydro-pneumatic suspension is compared with the one with single accumulator hydro-pneumatic suspension in both time domain and frequency domain. The result shows that the twin-accumulator hydro-pneumatic suspension system gives worthwhile improvements in ride comfort compared with the single accumulator hydro-pneumatic suspension,and it is more suitable for off-road vehicle.

Analytical calculation method and simulation of deformation and stress of Z-type guide arm for interconnected air suspensions

To design and check the strength of the Z-type guide arm of interconnected air suspensions for semi-trailers rapidly and effectively,this paper proposes the analytical calculation methods of its deformation and stress.First,based on the guide arm structure,it is marked as two parts by its mountpoint on the axle as the boundary.The part containing the eye was marked as Arm-1.The other part was marked as Arm-2.Then the analytical formulas of their stiffness and stress were derived,respectively.With a case study,the deformation and the stress were computed and simulated.The results show that the values computed are close to those simulated.The relative deviations are not more than 5.0%.The results show that the analytical formulas are acceptable.Moreover,it can be seen that for the superimposed Arm-1,when the other structural parameters are fixed,the position of the maximum stress is affected by the thickness ratio of the end thickness to the root thickness for each piece.Finally,a stiffness test was performed on the Z-type guide arm.The results show that the computed stiffness values are closed to those tested and the relative deviations are not more than 3.5%.This further verified the validity of the established model and methods.

发射车多轴连通式油气悬架的连通耦合效应

重载导弹发射车多使用4轴连通式双气室油气悬架,为了研究其连通耦合效应,以便对发射车设计进行参考。在2轴连通式油气悬架数学模型的基础上,基于AMESim软件分别建立2轴/4轴连通式双气室油气悬架系统的仿真模型,在几种不同信号频率与相位激励下分析了多轴连通式双气室油气悬架系统的连通耦合效应影响。结果表明:连通式油气悬架在低频激励作用下具有明显的阻尼特性。4轴连通式悬架系统与2轴连通式悬架系统相比,其外特性具备明显优势。连通式油气悬架系统受低频激励时外特性表现比较激烈,而在受高频激励时外特性表现良好,这说明系统在处于高频环境时更能衰减系统的不同步振动。

车辆电液馈能型互联悬架特性分析

为了提高馈能悬架的能量回收效果及动力学性能,提出了一种车辆电液馈能型互联悬架结构。根据流量/压降之间的关系,建立了整车7自由度与电液馈能型互联悬架的耦合数学模型,通过正弦激励对车辆电液馈能型互联悬架进行阻尼特性和馈能特性仿真。以四轮随机路面为输入,分析悬架对车辆的平顺性、行驶稳定性的影响。结果表明:阻尼力、馈能功率与激励频率、幅值成正比,馈能功率波动与之成反比,馈能效率随幅值、频率增大而先增大后减小;随机路面下,与被动悬架相比,电液馈能型互联悬架的俯仰模式、侧倾模式均可以改善动力学性能的同时实现振动能量的回收。

四轴互连油气悬架稳定性分析

对于多轴车辆而言,常见的单轴、两轴互连油气悬架系统大多无法有效控制车身的振动。针对这一问题,结合同侧互连与X型互连两种形式,设计四轴车辆的悬架互连形式。对比分析了侧倾和俯仰工况下四轴互连悬架与单轴连通式悬架的力矩以及刚度特性,并且分析了关键参数对于悬架刚度的影响。通过联合仿真对比单轴互连悬架以及四轴互连悬架的操纵稳定性。结果表明,四轴互连悬架大幅提高了悬架的侧倾刚度以及俯仰刚度。通过联合仿真对比可知,四轴互连悬架的侧倾角,俯仰角以及横向载荷转移率均小于单轴互连悬架,车身稳定性更好。

轻型高机动火箭炮连通式油气悬架发射振动性能

针对新一代超轻型高机动火箭炮发射过程中的冲击作用对车身垂直振动的影响,基于两轴连通式油气悬架,建立四自由度1/2整车的数学模型,并用AMESim软件搭建纯轮胎支撑、混合支撑和纯支腿支撑3种方式下的发射仿真模型。结果表明:在纯轮胎支撑下火箭炮系统的响应较差,车身的垂向位移和垂向加速度的幅值较大,不利于火箭炮发射,而在混合支撑和纯支腿支撑条件下系统响应较好。

液压互联悬架电磁平衡阀控制研究

液压互联悬架(hydraulically interconnected suspension,HIS)系统油缸内泄会直接影响其动态性能,为保证HIS系统的抗侧倾性能,文章提出一种基于电磁阀平衡两侧油路油压的解决方法,并对其控制策略进行分析。首先建立HIS模型,分析油路压力差对电磁阀平衡时间的影响,并进行实验验证;然后采用模糊控制方法实现对电磁阀开闭控制,通过MATLAB/Simulink对车辆行驶状态仿真,验证所提出的控制策略的有效性;最后进行实车试验与仿真结果分析。结果表明,该文提出的电磁平衡阀控制方法能有效平衡油缸内泄造成的两侧油路油压差。

刚度阻尼可调抗侧倾液压互联悬架动力学特性研究

为了更好兼顾车辆的操稳性和平顺性,提出一种刚度阻尼可调式抗侧倾液压互联悬架系统。该系统在被动式抗侧倾液压互联悬架的基础上增加了一组蓄能器,通过控制电磁阀的开闭和改变可调阻尼阀的节流面积,实现整车的刚度阻尼可调。利用Simulink软件搭建安装刚度可调抗侧倾液压互联悬架车辆动力学模型,搭建刚度可调抗侧倾液压互联悬架系统的实验台架,通过实验验证模型的准确性及可行性,以动力学模型为基础进行液压互联悬架系统参数匹配设计。最后,通过整车的操稳性和平顺性仿真验证了安装该系统的车辆可获得优异的操纵稳定性和平顺性。