基于嵌入式的装载机自动变速系统研究

该文设计的轮式装载机自动变速系统以嵌入式系统(ARM9)为硬件平台,实时操作系统(μC/OS-Ⅱ)为软件平台,根据对熟练驾驶员操纵经验的总结,选择最符合装载机自动变速的换挡点参数,建立不同工况下ZL50装载机模糊换挡策略。这种换挡策略符合轮式装载机的换挡要求,改善了车辆在各种特殊工况下的换挡品质,减少了换挡次数,避免了循环换挡的发生,有效地缓解了驾驶员的换挡疲劳。     

基于驾驶意图识别的DCT模糊换挡控制策略研究

针对汽车行驶时出现的频繁换挡问题,利用模糊推理方法对驾驶员驾驶意图进行了辨识,并对传统换挡控制策略下的双离合自动变速器换挡性能进行了研究。在双离合自动变速器传统换挡控制策略以及驾驶意图识别的基础上,提出了双离合自动变速器模糊换挡控制策略;建立了基于Matlab/Simulink的双离合自动变速器模糊换挡控制策略仿真模型,通过与传统换挡控制策略下的双离合自动变速器换挡性能仿真结果的对比,验证了基于驾驶意图识别的双离合自动变速器模糊换挡控制策略的有效性。研究结果表明:该换挡控制策略可以有效降低车辆的换挡次数,消除了车辆行驶时发生的频繁换挡现象,提高了驾驶员的乘坐舒适性以及汽车行驶安全性。     

轮式装载机模糊自动变速技术的研究

提出了装载机的综合性模糊换挡策略.其基本思路是利用各种信息判断车辆处于何种运行状态,执行车辆在该状态下的换挡策略.首先给出各工况的识别方法,然后建立了各典型工况下的模糊换挡策略,并给出了换挡可行性分析原理.台架试验验证了该换挡控制策略可以判断车辆的各种典型工况,而且能够应用该工况下的换挡策略进行换挡操作.     

装载机铲掘作业的轨迹规划

为给装载机的铲掘作业寻找一条能耗较小的铲掘轨迹,根据经验及有关文献给出的较理想的直线和曲线两种铲掘作业的轨迹方程,经过对装载机铲掘作业的轨迹规划及运动学建模,实现铲掘轨迹由直角坐标空间向关节空间转换以及由关节空间向驱动空间转换,得到动臂油缸和转斗油缸的驱动方程,并给出铲斗在实现铲掘轨迹的过程中所受的作用力。对在ADAMS环境下ZL40装载机仿真模型进行仿真,结果表明,装载机在同样时间内完成同样的作业量下,直线铲掘轨迹所作的总功小于曲线铲掘轨迹。     

车用自动变速器多工况换挡规律设计与动态修正

设计了某液力自动变速器组合型动力性换挡规律。基于发动机动态特性,采用以车速、油门开度、加速度为输入参数的模糊控制对换挡规律进行了修正,设计了车速衰减动力换挡规律对坡道工况进行修正。仿真结果表明,动态修正后的换挡规律使车辆具有更好的动力性,并能根据驾驶员意图进行相应的升降挡操作;坡道工况下换挡规律的修正策略能有效解决上坡行驶时的换挡循环和下坡行驶升至高挡的问题,避免了频繁换挡。     

基于发动机在环重型车C-WTVC循环油耗影响性研究

以某款重型柴油车为研究对象,基于发动机在环平台采用C-WTVC测试循环,研究不同换挡策略和不同滑行阻力对油耗的影响。文中通过对高挡位、居中挡位、偏低挡位3种驾驶换挡策略和相同类别车辆选取最大、居中、较小3组不同滑行系数对循环油耗的影响分析。结果发现：驾驶换挡策略不同循环油耗最大偏差为4.4%,最小偏差为0.99%,高挡位驾驶换挡策略的循环油耗最低。市区道路采用低挡位驾驶换挡策略发动机输出功最小,市郊路况不同驾驶换挡策略做功无明显差异,高速路况采用较高挡位输出功最小;不同滑行阻力导致油耗最大偏差为16.46%,最小偏差为6.96%,油耗结果随着滑行阻力增大而增大。分析比较该测试循环市区路况与市郊路况中不同换挡策略、不同滑行系数的油耗试验结果差异,为重型车自动换挡系统的研发与提升燃油经济性提供借鉴。     

发动机与液力变矩器的主次工况功率匹配方法研究

为避免装载机传动系统因功率过剩导致能源浪费，或因功率不足影响作业性能，提出发动机与液力变矩器的主次工况功率匹配方法。以装载机V型工况为基础，以油门信号、档位信号和制动信号为6段式循环工况的划分依据，将其细分为11个工况片段，再进一步归类为铲掘、举升、起步和匀速4个牵引阶段，结合装载机不同循环阶段的主次工况，进行发动机和液力变矩器的功率匹配研究。利用主次工况法对不同牵引阶段下装载机液压系统的功率与发动机的油门开度进行分析，并结合发动机与液力变矩器的共同工作特性得出，在铲掘与举升阶段，发动机几乎工作在额定功率点，应尽量避免超载；而在起步与匀速阶段，发动机的输出扭矩点相对较低，具有承受部分负载波动的能力，且应尽可能地工作在经济燃油区间。进一步，构建装载机机电液系统联合模型，对发动机变功率控制下的主次工况进行对比与验证。基于箱线图的工程机械主次工况分析法和装载机的牵引工况构建方法为发动机与液力变矩器的分工况功率匹配奠定基础，也为车辆传动系统的效能优化提供参考。     

基于计算力矩法的装载机工作装置轨迹控制

为了实现装载机工作装置铲掘作业时的轨迹跟踪控制,建立装载机工作装置的运动学及动力学模型,采用计算力矩法设计装载机铲掘作业的轨迹跟踪控制器,并根据装载机工作装置在作业时的受力情况加入作业阻力补偿。在Matlab/Simulink环境下建立装载机工作装置运动学、动力学模型及具有作业阻力补偿的计算力矩法控制器模型,并将在Solidworks环境中建立的ZL50装载机三维模型导入ADAMS。经ADAMS-Matlab联合仿真的结果表明,具有作业阻力补偿的计算力矩法可以实现装载机工作装置铲掘作业时所期望轨迹的高精度的跟踪控制。     

干式DCT换挡模糊时间决策及转矩协调控制

基于自主开发的5速干式双离合器自动变速器(Dual clutch transmissions,DCT),为充分反映驾驶员意图并改善不同行驶工况下DCT的换挡品质,从系统层面探讨发动机与双离合器间的转矩协调控制问题,推导换挡过程发动机转速及离合器传递转矩的计算公式。考虑该DCT物理结构特征,建立5自由度换挡动力学方程,简化后分别得到2自由度滑摩阶段模型和单自由度在挡运行模型。根据换挡品质要求量化换挡控制目标,分析换挡过程发动机与离合器的转速和转矩特性,提出模糊换挡时间决策和基于DCT动态模型的转矩协调控制策略。在Matlab/Simulink软件平台上,搭建DCT换挡控制仿真模型,对驾驶员不同意图下DCT的升、降挡过程进行仿真分析,并开展实车转毂试验。仿真及试验结果表明,所提出基于模型的转矩协调控制策略不仅有效体现了驾驶员换挡意图,改善了DCT换挡品质,而且能够较好地适应各种换挡工况,具有较强的鲁棒性。     

装载机变速挡位三例故障的排除

<正>柳工CLG856型装载机挡位控制采用机电一体化技术,其微机控制的变速自动换挡操作和多种运行换挡保护功能,为该型机的修理提出了新的要求,现介绍几种常见挡位故障的检测与排除方法。1.操纵前进或后退挡均无行走发动机高速运转,但机器不能行     

基于BP神经网络优化算法的工程车辆挡位判断的训练及仿真

为了克服工程车辆重载作业时,传动系统效率大幅下降的问题,一般采用自动换挡的办法,以实现对负载的适应,提高传递效率。所以选择一种合适的换挡规律是非常重要的。由于车辆的状态与最佳挡位之间存在非线性,若其关系以相应的数据的形式给出,可直接用所获得的数据对人工神经网络进行离线训练,讨论了建立在人工神经网络基础上的工程车辆挡位判断方法,以三参数换挡规律为例对网络进行了训练,并给出了MATLAB仿真结果。     

A supervisor-based neural-adaptive shift controller for automatic transmissions considering throttle opening and driving load

Recently, many passenger cars have adopted automatic transmissions for shifting gears, and thus the smooth and precise control of gear shifts of passenger car automatic transmissions has become more and more essential for the riding comfort of vehicles equipped with automatic transmissions. In this article, a neural network-based supervisor for an automotive shift controller considering the throttle opening, variations in throttle opening, and the driving load is presented. For using the driving load information, an, observer-based driving load estimation algorithm is proposed. A proportional-integral-derivative controller along with an open loop controller is used as a low level controller for controlling the gear shifts, and a supervisory controller for properly adapting the shift control parameters of the low level shift controller is designed using ANFIS. To evaluate the control performance of the proposed supervisor-based shift controller, both simulation studies and experimental studies are performed for various shifting situations.     

Shifting Rule Modification Strategy of Automatic Transmission Based on Driver-vehicle-road Environment

Accidental or frequent shift often occurs when the shifting rule is built based on traditional two parameters (I.e., velocity and throttle), because the speed of engine varies slower than change of throttle opening. Currently, modifying shift point velocity value or throttle by throttle change rate is one of common methods, but the results are not so satisfactory in some working condition such as uphill. The reason is that these methods merely consider throttle change rate which is not enough for a car driving in driver-vehicle-road environment system. So a novel fuzzy control modification strategy is proposed to avoid or reduce those abnormal shift actions. It can adjust shifting rule by the change rate of throttle, current gear position and road environment information, while different gear position and driving environment get corresponding modification value. In order to compare the results of shifting actions, fuel consumption and braking distance, emergent braking in level road and extra-urban driving cycle(EUDC) working conditions with fuzzy shifting schedule modification strategy are simulated digitally. Furthermore, a hardware-in-the-loop simulation platform is introduced to verify its effect in slope road condition according to the ON/OFF numbers of solenoid valve in hydraulic system. The simulation results show that the problem of unexpected shift in those working conditions may be resolved by fuzzy modification strategy. At last, it is concluded that although there is some slight decline in power performance in uphill situation, this fuzzy modification strategy could correctly identify slope of road, decrease braking distance, improve vehicle comfort and fuel economy effectively and prolong the life of clutch system. So, this fuzzy logic shifting strategy provides important References for vehicle intelligent shifting schedule.     

双离合器式自动变速器选换档控制系统的设计

介绍了基于MC9S12DT128B单片机的双离合器式自动变速器(DCT)选换档控制系统的设计.详细阐述了系统的工作原理、硬件接口电路和软件设计.该系统利用PWM信号控制直流电机,实现选换档过程的自动化.     

City-Bus-Route Demand-based Efficient Coupling Driving Control for Parallel Plug-in Hybrid Electric Bus

Recently,plug?in hybrid electric bus has been one of the energy?e cient solutions for urban transportation. However,the current vehicle e ciency is far from optimum,because the unpredicted external driving conditions are di cult to be obtained in advance. How to further explore its fuel?saving potential under the complicated city bus driving cycles through an e cient control strategy is still a hot research issue in both academic and engineering area. To realize an e cient coupling driving operation of the hybrid powertrain,a novel coupling driving control strategy for plug?in hybrid electric bus is presented. Combined with the typical feature of a city?bus?route,the fuzzy logic inference is employed to quantify the driving intention,and then to determine the coupling driving mode and the gear?shifting strategy. Considering the response deviation problem in the execution layer,an adaptive robust controller for electric machine is designed to respond to the transient torque demand,and instantaneously compensate the response delay and the engine torque fluctuation. The simulations and hard?in?loop tests with the actual data of two typical driving conditions from the real?world city?bus?route are carried out,and the results demonstrate that the pro?posed method could guarantee the hybrid powertrain to track the actual torque demand with 10.4% fuel economy improvement. The optimal fuel economy can be obtained through the optimal combination of working modes. The fuel economy of plug?in hybrid electric bus can be significantly improved by the proposed control scheme without loss of drivability.     

GEAR POSITION DECISION METHOD OF AUTOMATED MECHANICAL TRANSMISSION BASED ON FUZZY INFERENCE

０ＩＮＴＲＯＤＵＣＴＩＯＮＧｅａｒｐｏｓｉｔｉｏｎｔａｃｔｉｃｓｉｓｏｎｅｏｆｋｅｙｔｅｃｈｎｏｌｏｇｉｅｓｏｆａｕｔｏｍａｔｅｄｍｅｃｈａｎｉｃａｌｔｒａｎｓｍｉｓｉｏｎ（ＡＭＴ），ｗｈｉｃｈｒｅａｌｉｚｅｓａｕｔｏｍａｔｉｃｔｒａｎｓｍｉｓｉｏｎ...     

自动换档控制技术在拖拉机上的应用

在拖拉机上应用自动换档控制技术,可使驾驶员从繁重的换档操作中解放出来.通过对电控机械式自动变速箱换档过程的分析,以车辆系统动力学模型为基础,提出了以换档时间为控制目标,在拖拉机上应用自动换档控制技术的工程实施方案.     

基于机器视觉的汽车换挡面板自动分类方法

针对报废汽车企业对不同型号汽车换挡面板自动分类的需求,提出了一种基于机器视觉的面板自动分类方法.该方法首先使用Blob分析对图像进行预处理,分割出图像中的换挡面板目标对象,接着提取被分割图像的11个形状特征作为特征向量,利用特征向量训练多层感知器(Multi-Layer Perceptron,MLP),最后使用完成训练...     

对自动变速器中单向离合器消除降档冲击的功能分析

针对自动变速器在自动变换档位时的冲击问题进行研究,简要介绍变速原理,并在此基础上对如何采用单向离合器消除换档特别是降档时的冲击问题进行了详细阐述,并提出了消除换档冲击的几种方法。     

GEAR POSITION DECISION METHOD OF AUTOMATED MECHANICAL TRANSMISSION BASED ON FUZZY INFERENCE

A gear position decision method used in automated mechanical transmission is introduced. The algorithm of the mechod is composed of a driving environment and driver's intention estimator, the shift schedules suit for each typical driving environment and driver's intention situation, and a inference ligic to determine the most proper gear position for the present situation. The estimator identifies the driving environment and driver's intention features which are divided into some typical models. Based on the identified results, the algorithm works out the best gear position. It just simulates the course of a driver's making gear position decision when driving a automobile with manual transmission. The test results show that the automated mechanical transmission with the method gives less unnecessary shifting and more proper gear position than common shift schedules.