Real-Time Co-optimization of Gear Shifting and Engine Torque for Predictive Cruise Control of Heavy-Duty Trucks

Fuel consumption is one of the main concerns for heavy-duty trucks.Predictive cruise control(PCC)provides an intriguing opportunity to reduce fuel consumption by using the upcoming road information.In this study,a real-time implementable PCC,which simultaneously optimizes engine torque and gear shifting,is proposed for heavy-duty trucks.To minimize fuel consumption,the problem of the PCC is formulated as a nonlinear model predictive control(MPC),in which the upcoming road elevation information is used.Finding the solution of the nonlinear MPC is time consuming;thus,a real-time implementable solver is developed based on Pontryagin’s maximum principle and indirect shooting method.Dynamic programming(DP)algorithm,as a global optimization algorithm,is used as a performance benchmark for the proposed solver.Simulation,hardware-in-the-loop and real-truck experiments are conducted to verify the performance of the proposed controller.The results demonstrate that the MPC-based solution performs nearly as well as the DP-based solution,with less than 1%deviation for testing roads.Moreover,the proposed co-optimization controller is implementable in a real-truck,and the proposed MPC-based PCC algorithm achieves a fuel-saving rate of 7.9%without compromising the truck’s travel time.

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.

Computation of rolling resistance caused by rubber hysteresis of truck radial tire

Applying the results of stress and strain calculated by 3D finite element model of truck radial tire 11.00R20, a MATLAB program used to compute rolling resistance of the tire caused by hysteresis rolling resistance (HRR) is worked out. The HRR distribution on different part of tire section, and the effects of speed, load, internal pressure and the width of the rim on HRR are analyzed. The analysis results showed that energy loss produced by tread rubber contributes the most part to HRR of the whole tire, and that to decrease the HRR, the hysteresis factor of the tread rubber should be reduced, and the distribution of the stress and strain on the section be optimized.

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.

Global-Local Finite Element Analysis for Predicting Separation in Cord-Rubber Composites of Radial Truck Tires

A global-local finite element modeling technique is employed in this paper to predict the separation in steel cord-rubber composite materials of radial truck tires. The local model uses a finite element analysis in conjunction with a glob-al-local technique in ABAQUS. A 3-dimensional finite element local model calculates the maximum cyclic shear strain of an interface between steel cord and rubber materials at the carcass ply shoulder region. It is found that the maximum cyclic shear strain is reliable as a result of the analysis of carcass ply separation in radial truck tires. Using the analysis of the local model, a study of the cyclic shear strain is performed in the shoulder region and used to deter-mine the carcass ply separation. The effect of the change of carcass ply design on the separation in steel cord-rubber composite materials of radial truck tires is discussed.

双酰肼类材料CSC920在全钢载重子午线轮胎基部胶中的应用

研究双酰肼类材料CSC920(简称CSC920)对全钢载重子午线轮胎基部胶性能的影响。结果表明:CSC920对天然橡胶有较好的改性效果,能显著加快胶料的硫化反应速度,增大胶料的门尼粘度;加入CSC920后,基部胶的定伸应力、拉伸强度和弹性均有所提升,滚动阻力和生热明显降低;混炼过程中,CSC920在氧化锌之前加入,基部胶的物理性能较好,压缩生热明显降低,CSC920在氧化锌之后加入,可以起到抗硫化返原作用,基部胶的物理性能有所改善,但降低生热效果不明显。

Data from Twenty-Three FRB’s Confirm the Universe Is Static and Not Expanding

Fast Radio Bursts from far away galaxies have travelled through the IGM and provide a tool to study its composition. Presently there are 23 FRB’s whose host galaxies have been identified and the redshift found. This gives us the opportunity to test Dispersion Measure versus redshift predictions made by two models. The Macquart relation for an expanding Universe and the New Tired Light relationship in a static universe. In New Tired Light, redshifts are produced when a photon is absorbed and re-emitted by the electrons in the IGM which recoil on both occasions. Some of the energy of the photon has been transferred to the kinetic energy of the recoiling electron. The photon has less energy, a lower frequency and a longer wavelength. It has been redshifted. Since dispersion is due to an interaction between radio signals and these same electrons one would expect a direct relationship between DM and redshift in the New Tired light model. The relation is DM=(mec/2hre)ln(1+z)and contains no adjustable parameters—just a combination of universal constants related to the electron and photon. Notice that the relation is independent of the electron number density ne since a change in ne affects both the DM and redshift equally. A graph of DM versus ln(1 + z) will be a straight line of gradient (mec/2hre)and, using SI units, substituting for the constants gives 7.318 × 1025 m−2. Using the data from the 23 well localized FRB’s, with the weighting of the DM’s for expansion removed (so that the data corresponds to a static universe), a graph of DM versus ln(1 + z) has a gradient of 6.7 × 1025 m−2—9% below the predicted (mec/2hre). The Macquart relation involves highly processed data and adjustable parameters to allow for “dark energy” and “dark matter” (neither of which has yet been found) and can be reduced to DM = 850z (in units of pc∙cm−3). Using the data from this set of localized FRB’s gives a trendline with gradient 1.10 × 103 pc∙cm−3—almost 30% higher than that predicted in an expanding universe model. The FRB data clearly comes down in favour of a static universe rather than an expanding one. Combining the DM-z relationship for the 23 well localized FRB’s, with the Hubble diagram, drawn using the NED-D compilation of redshift independent extragalactic distances, produces a value of “ne” the mean electron number density of the IGM, of ne=0.48 m−3close to the value ne=0.5 m−3, long since predicted by NTL.

0.22+18×0.20CCST钢丝帘线在全钢载重子午线轮胎胎体中的应用

研究0.22+18×0.20CCST钢丝帘线在全钢载重子午线轮胎胎体中的应用。结果表明,以0.22+18×0.20CCST钢丝帘线替代3+9+15×0.175+0.15钢丝帘线用于295/80R22.518PR全钢载重子午线轮胎胎体中,可在满足轮胎承载性能的前提下有效提高轮胎的高速性能和耐久性能,同时还能减小轮胎的质量和降低成本。

2+7×0.30ST钢丝帘线在轻型载重子午线轮胎带束层中的应用

研究以2+7×0.30ST钢丝帘线替代3×0.20+6×0.35HT钢丝帘线在7.50R16 14PR轻型载重子午线轮胎带束层中的应用。结果表明:与3×0.20+6×0.35HT钢丝帘线相比,2+7×0.30ST钢丝帘线整体呈椭圆形排布,帘线直径相同,强度更高;将2+7×0.30ST钢丝帘线应用于带束层中,成品轮胎的充气外缘尺寸符合国家标准要求,耐久性能相当,强度性能和高速性能略有提升,滚动阻力降低,单胎质量减小。

LT325/50R22 122S全路况半钢轻型载重子午线轮胎的设计

介绍LT325/50R22 122S全路况半钢轻型载重子午线轮胎的设计。结构设计:外直径882 mm,断面宽344mm,行驶面宽度284 mm,行驶面弧度高13 mm,胎圈着和直径562.8 mm,胎圈着和宽度274 mm,断面水平轴位置(H1/H2) 1.033,胎面花纹为对称形式,花纹主/横沟深度12.7 mm,花纹饱和度58.66%,花纹周节数28。施工设计:带束层采用双层3+8×0.23ST钢丝帘布,胎体采用3层1440dtex/2聚酯帘布,成型采用二段成型机,硫化采用B型双模轮胎定型硫化机。成品轮胎试验结果表明,轮胎的充气外缘尺寸、强度性能、高速性能及耐久性能均符合相应标准和设计要求。

0.225+18×0.205CCST钢丝帘线在全钢载重子午线轮胎胎体中的应用

研究0.225+18×0.205CCST钢丝帘线在全钢载重子午线轮胎胎体中的应用,并与0.17+5×0.215+10×0.235CCST钢丝帘线和0.25+6+12×0.225HT钢丝帘线进行对比。结果表明:采用0.225+18×0.205CCST钢丝帘线的成品轮胎的强度和高速性能相当,耐久性能提高,滚动阻力下降,单胎质量减小,综合成本降低。

3+8×0.21ST钢丝帘线在全钢轻型载重子午线轮胎胎体中的应用

研究3+8×0.21ST钢丝帘线在全钢轻型载重子午线轮胎胎体中的应用。结果表明:与3×0.24/9×0.225CCHT钢丝帘线相比,3+8×0.21ST钢丝帘线的直径和线密度小,粘合性能相当,压延及裁断工艺性能良好;以3+8×0.21ST钢丝帘线替代3×0.24/9×0.225CCHT钢丝帘线用于7.50R16LT全钢轻型载重子午线轮胎胎体中,轮胎的充气外缘尺寸、强度性能、高速性能和耐久性能符合国家标准要求,轮胎的舒适性更好,滚动阻力降低,单胎质量减小,成本降低。

基于Abaqus软件和正交试验的12R22.5全钢载重子午线轮胎有限元优化设计

基于Abaqus有限元分析软件,对12R22.5全钢载重子午线轮胎外轮廓参数正交试验方案进行分析,得到优选方案。对优选方案进行仿真分析,对比Mises应力、最大应变能密度梯度、接地面积、最大接地压力等指标,选择轮胎行驶面高度为4 mm、冠弧半径为600 mm、肩弧半径为170 mm为最优方案。

基于Abaqus软件的12R22.5全钢载重子午线轮胎带束层钢丝帘线的有限元优化设计

基于Abaqus软件,建立12R22.5全钢载重子午线轮胎有限元分析模型,对带束层采用0.37+6×0.32ST,4+3×0.33ST,3×0.20+6×0.35HT钢丝帘线的轮胎进行仿真对比,分析带束层部位最大Mises应力和最大应变能密度梯度、接地面积和最大接地压力等指标。结果表明,1^(#)—3^(#)带束层可以根据需求选择使用0.37+6×0.32ST或4+3×0.33ST钢丝帘线。

A Novel Integrated Stability Control Based on Differential Braking and Active Steering for Four-axle Trucks

Di erential braking and active steering have already been integrated to overcome their shortcomings. However, existing research mainly focuses on two-axle vehicles and controllers are mostly designed to use one control method to improve the other. Moreover, many experiments are needed to improve the robustness; therefore, these control methods are underutilized. This paper proposes an integrated control system specially designed for multi-axle vehicles, in which the desired lateral force and yaw moment of vehicles are determined by the sliding mode control algorithm. The output of the sliding mode control is distributed to the suitable wheels based on the abilities and potentials of the two control methods. Moreover, in this method, fewer experiments are needed, and the robustness and simultaneity are both guaranteed. To simplify the optimization system and to improve the computation speed, seven simple optimization subsystems are designed for the determination of control outputs on each wheel. The simulation results show that the proposed controller obviously enhances the stability of multi-axle trucks. The system improves 68% of the safe velocity, and its performance is much better than both di erential braking and active steering. This research proposes an integrated control system that can simultaneously invoke di erential braking and active steering of multi-axle vehicles to fully utilize the abilities and potentials of the two control methods.

Basic Properties of Pyrolysis Carbon Black of Waste Tyres and Application of Pyrolysis Carbon Black in Transition Layer Rubber of All Steel Radial Tire

The main chemical composition of pyrolysis carbon black of waste tires is C,O,Cu,Zn and so on.The content of ash and fine powder in pyrolysis carbon black is high,and the 300%elongation stress is high.The difference between pyrolysis carbon black and furnace black N326,which is commonly used in rubber,is obvious compared with chemical property.The pyrolysis carbon black was used to replace furnace black N326 in the transition layer of all steel load Radial tire rubber through experimental study.It was found that the compression heat generation and dynamic loss(Tanδ)of the blend rubber before and after aging were obviously reduced,the elongation at break and resilience increased,while the tensile stress and tear strength decreased by 100%and 300%,but the hardness and tensile strength changed little before and after aging.According to the latest raw material price calculation,15 used tire pyrolysis carbon black instead of furnace carbon black N326 used in all steel Radial tire transition layer rubber application,excluding labor costs,electricity and equipment depreciation,a ton of blended rubber saves about$22.86 in production costs.

0.23+18×0.21ST超高强度钢丝帘线在全钢载重子午线轮胎胎体中的应用

研究0.23+18×0.21ST超高强度钢丝帘线在全钢载重子午线轮胎胎体中的应用。结果表明:与0.17+5×0.215+10×0.235CCST钢丝帘线相比,0.23+18×0.21ST钢丝帘线破断力更高、线密度更大、承载性能更强;以其替代0.17+5×0.215+10×0.235CCST钢丝帘线用于全钢载重子午线轮胎胎体,成品轮胎的充气外缘尺寸符合国家标准要求,强度和耐久性能提高,轮胎使用寿命延长,同时可降低生产成本。

0.37+6×0.32ST钢丝帘线在轻型全钢载重子午线轮胎带束层中的应用

研究0.37+6×0.32ST钢丝帘线在轻型全钢载重子午线轮胎带束层中的应用。成品试验结果表明,采用0.37+6×0.32ST钢丝帘线替代3×0.20+6×0.35HT钢丝帘线用于7.50R1612PR轮胎带束层,成品轮胎耐久性能明显提高,充气外缘尺寸、强度性能满足国家标准和企业标准要求,同时可以减小轮胎质量,降低生产成本。

3+8×0.21ST钢丝帘线在全钢载重子午线轮胎胎圈包布中的应用

研究3+8×0.21ST钢丝帘线在全钢载重子午线轮胎胎圈包布中的应用。结果表明:与3+9×0.22+0.15HT钢丝帘线相比,3+8×0.21ST钢丝帘线的渗胶性能更好,帘线直径较小,可减小压延厚度和帘布质量,提高强度;以3+8×0.21ST钢丝帘线替代3+9×0.22+0.15HT钢丝帘线用于全钢载重子午线轮胎胎圈包布,成品轮胎的耐久性能提升,单胎质量减小,成本降低,有利于轮胎轻量化。

4+3×0.33ST超高强度钢丝帘线在全钢载重子午线轮胎带束层中的应用

研究4+3×0.33ST钢丝帘线替代2+7×0.30ST钢丝帘线在全钢载重子午线轮胎带束层中的应用。结果表明:与2+7×0.30ST钢丝帘线相比,4+3×0.33ST钢丝帘线单丝直径大,刚度高,可增强轮胎冠部刚性,减少不规则磨损;采用4+3×0.33ST钢丝帘线生产的成品轮胎的外缘尺寸和强度性能均符合国家标准要求,耐久性能更优,轮胎使用寿命延长,同时由于帘布厚度减小,胶料质量减小,生产成本降低。