Vertical Tire Forces Estimation of Multi-Axle Trucks Based on an Adaptive Treble Extend Kalman Filter

Vertical tire forces are essential for vehicle modelling and dynamic control.However,an evaluation of the vertical tire forces on a multi-axle truck is difficult to accomplish.The current methods require a large amount of experimental data and many sensors owing to the wide variation of the parameters and the over-constraint.To simplify the design process and reduce the demand of the sensors,this paper presents a practical approach to estimating the vertical tire forces of a multi-axle truck for dynamic control.The estimation system is based on a novel vertical force model and a proposed adaptive treble extend Kalman filter(ATEKF).To adapt to the widely varying parameters,a sliding mode update is designed to make the ATEKF adaptive,and together with the use of an initial setting update and a vertical tire force adjustment,the overall system becomes more robust.In particular,the model aims to eliminate the effects of the over-constraint and the uneven weight distribution.The results show that the ATEKF method achieves an excellent performance in a vertical force evaluation,and its performance is better than that of the treble extend Kalman filter.

Estimation of Longitudinal Tire Force Using Nonlinearity Observer

Tire forces are the major forces propelling the road vehicles. They significantly affect the dynamic behavior of the vehicles. Estimation of the tire forces is essential in vehicle dynamics and control. This paper presents an observer-based scheme for estimation of the longitudinal tire force of electric vehicles in real time.? The observer is based on a nonlinearity observer method. The pole-placement technique is used for determination of the observer gains. Simulation results demonstrate that the observer is able to estimate the tire force successfully. The experiments are implemented on a single-wheel electric vehicle test rig. The test rig comprises an electric motor driven wheel and a free-rolling drum simulating vehicle-on-road situations. Experimental results confirm the effectiveness of the present scheme.

The Effect of Tire Design Parameters on the Force Transmissibility

A finite element modeling technique is employed in this paper to predict the force transmissibility of tire-cavity-wheel assembly under a free-fixed condition. The tire and wheel force transmissibility is factor in structure borne road noise performance. In order to improve structure borne noise, it is required to lower the 1st peak frequency of force transmissibility. This paper presents an application of finite element analysis modeling along with experimental verification to predict the force transmissibility of tire and wheel assembly. The results of finite element analysis for force transmissibility are shown to be in good agreement with the results from the indoor test. In order to improve structure borne noise, it is required to lower the 1st peak frequency of force transmissibility. And, the effect of the tire design parameters such as the density and modulus of a rubber and the cord stiffness on the force transmissibility is discussed. It is found that the prediction of the force transmissibility model using finite element analysis will be useful for the improvement of the road noise performance of passenger car tire.

大侧倾角下UniTire稳态侧倾侧偏工况侧向力模型

大侧倾角下,轮胎侧偏力学特性仅仅采用等效侧偏角的方法不能进行准确描述,还需要考虑侧倾对其他关键参数的影响。基于简单刷子模型,建立轮胎稳态侧倾侧偏工况侧向力物理模型,导出用于半经验建模的理论边界条件。采用定性分析及试验观察相结合的方法分析侧倾对侧偏刚度和摩擦因数的影响,并建立相应的半经验模型。根据理论边界条件,分析侧倾对UniTire稳态侧向力模型中曲率因子的影响,并提出新的曲率因子表达式。通过轮胎试验数据进行参数辨识,结果表明所建立的UniTire稳态侧向力模型具有很高的精度,并且能够表达大侧倾角下轮胎的力学特性。

废弃轮胎-砂地基抗震性能和恢复力模型研究

为研究废弃轮胎-砂构造地基的抗震性能,进行了6组轮胎-砂构造地基的拟静力试验,分析轮胎-砂单元体的堆砌方式、初始竖向荷载和碳纤维网片对构造地基的滞回性能的影响。在拟静力试验基础上用试验拟合法建立废弃轮胎-砂构造地基的恢复力模型。研究结果表明:废弃轮胎-砂构造地基的滞回曲线饱满,总体呈梭形,具有较好的耗能能力;轮胎-砂单元体错缝堆砌、增大随初始竖向荷载和增设碳纤维网片都有利于轮胎-砂构造地基参与耗能;轮胎-砂构造地基恢复力模型的滞回曲线计算结果和试验结果吻合程度较好,可以反映出试件的受力过程和主要受力特征。

State Estimation of Drive-by-Wire Chassis Vehicle Based on Dual Unscented Particle Filter Algorithm

Accurate vehicle dynamic information plays an important role in vehicle driving safety.However,due to the characteristics of high mobility and multiple controllable degrees of freedom of drive-by-wire chassis vehicles,the current mature application of traditional vehicle state estimation algorithms can not meet the requirements of drive-by-wire chassis vehicle state estimation.This paper proposes a state estimation method for drive-by-wire chassis vehicle based on the dual unscented particle filter algorithm,which make full use of the known advantages of the four-wheel drive torque and steer angle parameters of the drive-by-wire chassis vehicle.In the dual unscented particle filter algorithm,two unscented particle filter transfer information to each other,observe the vehicle state information and the tire force parameter information of the four wheels respectively,which reduce the influence of parameter uncertainty and model parameter changes on the estimation accuracy during driving.The performance with the dual unscented particle filter algorithm,which is analyzed in terms of the time-average square error,is superior of the unscented Kalman filter algorithm.The effectiveness of the algorithm is further verified by driving simulator test.In this paper,a vehicle state estimator based on dual unscented particle filter algorithm was proposed for the first time to improve the estimation accuracy of vehicle parameters and states.

智能轮胎关键监测技术的研究进展

介绍轮胎力预测、轮胎磨损检测和传感器自供能等智能轮胎关键监测技术的研究进展,并展望智能轮胎监测技术的发展趋势。目前轮胎力预测方法主要有拟合多项式算法和神经网络算法两种,前者大多只是得到径向力,后者可以获得径向力、横向力和纵向力;轮胎磨损检测方法主要是神经网络算法,通过分析加速度信号并提取特征值,进行神经网络训练来得到磨损数据;传感器自供能技术当前只是存在于学术层面的研究中,没有应用于实际中。我国互联网技术、大数据和人工智能技术不断发展以及技术实力提升,为智能轮胎监测技术的进一步研究打下了基础。

轮胎扁平比对汽车行驶舒适性的影响研究

以某乘用车为研究对象,分析轮胎轴头力和力矩响应,根据传递路径对配备不同扁平比轮胎的车辆进行整车行驶舒适性测试,结合主观评价,研究轮胎扁平比对汽车行驶舒适性的影响,结果表明同一车型配置大尺寸低扁平比轮胎后整车行驶舒适性变差.

轮胎六分力试验机线性数据监控方法的研究

对轮胎六分力试验机线性数据的监控方法进行了研究。结果表明:在小侧偏角下,暖胎对轮胎侧向力系数(F_(1))和回正力矩系数(T_(a1))的影响不大,采用F1和Ta1监控试验数据时可不用暖胎;采用控制轮胎监控F_(1)和T_(a1)时,需要考虑轮胎制造工艺偏差、试验机偏差、充气压力偏差和负荷偏差的影响;在小侧偏角下,模拟路面的附着力系数对F_(1)和T_(a1)的影响不大,在大侧偏角下,需要考虑模拟路面的附着力系数对F_(1)和T_(a1)的影响;采用本监控方案,可对轮胎六分力试验机线性数据进行监控,判定试验数据的合理性。

轿车子午线轮胎高速均匀性纵向谐波力的研究

对轿车子午线轮胎高速均匀性纵向谐波力进行研究。结果表明:轮胎纵向波动力1阶谐波(TFV1H)幅值随着轮胎速度的增大而增大,并呈几何式增长趋势;轮胎TFV1H幅值和速度的关系可用幂函数模型表示;不同轮胎的幂函数模型的2个系数不同,但其具有较好的线性关系;可以将轮胎TFV1H幅值和速度的关系确定为只有1个待定常数的幂函数模型。

硫化后充气压力和时间对航空轮胎性能的影响

选取27×7.7-15航空轮胎作为研究对象,研究硫化后充气压力和时间对航空轮胎性能的影响。分析胎体帘线张力与充气压力的关系以及帘线收缩率、收缩力与温度的关系,并通过热电偶测温法测量轮胎硫化后充气过程中温度随时间的变化情况,确定轮胎最小硫化后充气压力设为200 kPa,可以保证轮胎在胎体温度为160~170℃时出模胎体帘线不产生热收缩;硫化后充气时间设为1个硫化周期,可以保证轮胎冷却至环境温度。成品轮胎充气外缘尺寸及动态模拟试验验证了后充气压力和时间选取的合理性。

不同测试方法下的轮胎性能评价函数值研究

以235/55R19轿车子午线轮胎为例,采用稳态力和力矩试验法与动态侧偏扫掠法进行对比试验,并计算轮胎的性能评价函数值。结果表明:稳态力和力矩试验法得到的侧偏角为1°,4°时的侧向力函数(F函数)、负荷转移敏感度函数(G函数)、回正力矩函数(AT函数)值随垂向负荷呈线性变化,趋势与动态侧偏扫掠法基本一致;但动态侧偏扫掠法回正力矩波动大,导致AT函数值随垂向负荷的增大而波动大;稳态力和力矩试验法与动态侧偏扫掠法下的F函数值和H函数值差异较小,但差异随着垂向负荷的增大而增大;2种方法的G函数值和AT函数值差异均较大。

Prediction of Burst Pressure of a Radial Truck Tire Using Finite Element Analysis

This paper is concerned with the numerical prediction of the burst pressure of a radial truck tire. Even though relatively rare, the tire fracture or failure brings up a big accident. Especially, the tire burst or rupture is a rapid loss of inflation pressure of a truck and bus tire leading to an explosion. The tire burst pressure, under this extreme loading condition, can be predicted by identifying the pressure at which the cord breaking force of the composite materials is attained. Recently, the use of finite element analysis in tire optimal design has become widely popular. In order to determine the burst pressure of a radial truck tire, an axisymmetric finite element model has been developed using a commercial finite element code with rebar element. The numerical result shows that the bead wire among the various layers modeled the rebar element breaks off first in the radial truck tire. The finite element modeling with the rebar element on the bead wire of a radial truck tire is able to well predict the tire burst pressure identifying the pressure at which the breaking force of steel bead wires is reached. The model predictions of tire burst pressure should be correlated with test data, in which case the tire is hydro-tested to destruction. The effect of the design change with the different bead structure on the tire burst pressure is discussed.

Finite Element Analysis for Groove Wander Prediction of Passenger Car Tires with the Longitudinal Tread Grooves

A finite element modeling technique is employed in this paper to predict the groove wander of longitudinal tread grooved tires. In generally, groove wander is the lateral force acting on a vehicle’s wheel resulting from the combination of rain grooves. If the lateral force of tire is generated by groove wander, unexpected lateral motion of vehicle will happen and it makes drivers uncomfortable. This paper describes the effect of groove wander according to the shape condition of tire tread groove and highway groove using the finite element analysis based on a static loading or a steady-state rolling assumption. The road groove can be located anywhere relative to the longitudinal tread groove. Therefore, the lateral force of the tire is changing depending on the location of the groove road. The numerical results for groove wander prediction of the longitudinal tread grooved tires are compared with the subjective evaluation. It is found that the waveform for the tire with varying grooved road position has a peak-to-peak lateral force in order to estimate the rating of groove wander. The effect of the road groove width and the pitch length on the peak-to-peak lateral force of tire is discussed. It is found that the prediction of FEA-based groove wander model using finite element analysis will be useful for the reliability design of the tire tread pattern design.

车辆轮胎力的鲁棒估计方法研究

轮胎力的准确获取对车辆主动安全系统精确控制的实现至关重要。本文提出了一种轮胎力的鲁棒估计方法。在假设系统噪声特性为分布未知但有界的同时,该方法将集员滤波算法引入到轮胎力估计器的设计中,并结合强跟踪理论和序贯更新的思路对该算法进行优化。在此基础上,结合车轮转动动力学模型和双轨车辆动力学模型分别设计轮胎纵向力和侧向力估计器。最后,利用联合仿真平台对所提出的方案进行验证。结果表明:相较于卡尔曼滤波方案,改进的集员滤波方案能够获得更好的估计效果,且对系统噪声和道路状况的变化具有很好的鲁棒性。

基于轮胎加速度信号的胎路作用力估算模型

研究重载卡车对道路的破坏机制能够指导道路的设计与养护,有效延长道路的使用寿命.其中,针对复杂重载荷作用下道路病害研究对轮胎路面作用力测量的需求,本文提出了一种复合工况下胎路三向力的建模估算方法.以11.00R20型全钢载重子午线轮胎为研究对象,经过对结构的合理简化,利用ABAQUS有限元仿真软件以参数化建模方法建立了轮胎有限元模型,并验证了模型的有效性;以不同的垂向载荷、侧偏角、纵滑率、轮速和胎压设置了多种复合工况,并对轮胎模型进行了稳态滚动分析,获得了轮胎同一断面内衬层上多个观测点的加速度响应信号;对采集的加速度信号进行了滤波处理,并对比了不同信号的响应程度,选取其中特征较为明显的信号作为观测加速度信号;提取了观测加速度信号的特征,并结合胎压和轮速作为输入,建立了基于卷积神经网络(CNN)的复合工况下胎路三向力的回归解析模型;以模型对15个测试工况的估算结果,近似地描述了该模型的泛化能力,该模型下胎路三向力估算的平均绝对百分比误差均在7%以内,均方根误差不超过1 kN.结果表明,轮胎内衬层上的加速度信号与胎路作用力具有较高的相关性,基于加速度信号与卷积神经网络建立的模型能够有效地实现胎路三向力的同时估算,为道路病害研究提供了有价值的载荷信息.

汽车爆胎的载荷转移建模及仿真分析

汽车发生爆胎后容易造成交通事故,特别是在高速行驶的情况下,由爆胎引起的交通事故占比32%,其中死亡事故更是高达49%[1]。当高速行驶的汽车发生爆胎后,行驶路线会发生改变,并且汽车会处于横摆与侧翻的失控状态,所以对爆胎汽车的行驶状态进行研究是非常必要的。首先,通过研究汽车爆胎发生后,爆胎车轮的滚动半径变化,爆胎汽车姿态发生变化从而会使汽车转向系统的转向角及车轮侧偏角发生改变;其次,通过研究汽车爆胎发生后,汽车的重心将发生转移从而引起四个车轮上的垂直载荷发生转移,从而导致各个车轮上的侧偏力大小发生改变;最后,通过分析汽车爆胎过程中各个车轮侧偏角的改变以及垂向载荷的转移引起各个车轮上的侧偏力的改变,联合建立爆胎汽车二自由度操纵动力学模型。并利用Matlab/Simulink搭建仿真模型,得出汽车侧向加速度、横摆角速度的变化曲线。仿真结果表明,在车速为120km/h时,汽车发生爆胎的运动过程中,考虑垂向载荷转移的情况相比于没有考虑垂向载荷转移的情况更能准确描述爆胎汽车方向失稳的真实运动过程。

结构因素对轮胎模态及力传递特性的影响

研究带束层材料、带束层角度、三角胶高度和有无冠带层4种结构因素对轮胎模态和力传递特性的影响。结果表明:不同的带束层材料有不同的隔振性能;带束层角度与刚体模态频率呈正相关,但对空腔模态频率几乎无影响,带束层角度与轮胎力传递率呈正相关;三角胶高度与刚体模态频率呈正相关,但对空腔频率几乎无影响,三角胶高度与径向空腔及横向力传递率呈负相关;有无冠带层对轮胎模态频率影响较大,有冠带层轮胎比无冠带层轮胎径向模态频率大,且高阶模态更容易受其影响,而有无冠带层对横向刚体模态频率的影响呈负相关,有无冠带层与径向1阶和径向空腔力传递率呈正相关,与横向1阶力传递率呈负相关。

应用MSC MARC有限元分析软件优化27.00R49巨型工程机械子午线轮胎带束层结构

以27.00R49巨型工程机械子午线轮胎为例,应用MSC MARC2021有限元分析软件建立轮胎静态有限元模型,研究A方案带束层结构光面轮胎与带花纹轮胎的静负荷受力情况;B方案为A方案带束层结构的优化方案,对两种方案带束层结构的各层受力和轮胎接地印痕进行有限元分析,并与实测结果进行对比。结果表明,B方案带束层结构比A方案更优,有利于减少轮胎胎肩脱层问题。