Adaptive Clutch Engaging Process Control for Automatic Mechanical Transmission

Based on detail analysis of clutch engaging process control targets and adaptive demands, a control strategy which is based on speed signal, different from that of based on main clutch displacement signal, is put forward. It considers both jerk and slipping work which are the most commonly used quality evaluating indexes of vehicle starting phase. The adaptive control system and its reference model are discussed profoundly. Taking the adaptability to different starting gears and different road conditions as examples, some proving field test records are shown to illustrate the main clutch adaptive control strategy at starting phase. Proving field test gives acceptable results.

STUDY ON CONTROL STRATEGY OF CLUTCH STARTING FOR CAR WITH A METAL PUSHING BELT-PLANETARY GEAR CONTINUOUSLY VARIABLE TRANSMISSION SYSTEM

The automatic control of clutch starting in car with a metal pushingbelt-planetary gear continuously variable transmission (CVT) is a complex problem. A suited controlstrategy is required to realize quick and smooth start. A simulation state space equation isestablished on clutch staring control of a car with CVT by bond graph theory. According to the fuzzycontrol method with the expert system, a fuzzy control system of car starting process to weaken thejerk motion is introduced. The simulation results indicate that the jerk motion of clutch startingis below 10 m/s^3.

Application of clutch to clutch gear shift technology for a new automatic transmission

For the purpose of engineering development for a new 8-step speed automatic transmission,a simplified dynamic model for this gearbox was established and key parameters which affected the shift quality were analyzed.Aiming at four different shift types,the ideal characteristics of shift clutch and engine control were set up.By using torque estimation method,PI slip control algorithm and engine coordinated control principle,the control model and transmission controller were well developed for three shift phases which included rapid-fill phase,torque phase and inertia phase.The testing environment on the rig and prototype vehicle level was built and the testing results obtained in ultimate condition could verify the accuracy and feasibility of this shift control strategy.The peak jerk during shift process was controlled within ±2 g/s where the smooth gearshift was obtained.The development proposal and algorithm have a high value for engineering application.

Simulation study on starting of dual clutch transmission for tracked vehicles

In order to study the application of dual clutch transmission （DCT） on tracked vehicles, a simulation moclel and two control methods were performed for starting analysis. Based on a certain transmission of an existing tracked vehicle, a DCT structure was proposed. Matlab/Simulink was a dopted as a platform to develop the simulation model. The engine speed was controlled to follow the target speed as a launch strategy. Two control methods, a proportional integral derivative （ PID ） control method and a fuzzy control method, were proposed to control the engine throttle and oil pressure in order to track the target engine speed. Simulation results show that either the PID control or fuzzy control method can improve the starting performance compared with no loop control meth od. Fuzzy control method can lead a better starting quality compared with PID control method.

Developing Additive Technology for Wet Dual Clutch Transmissions

Wet dual clutch transmissions(W-DCTs) show overall benefits including excellent fuel efficiency,wide torque capacity range,long durability,driving comfort and sportiness.Many breakthroughs have been made to further improve the fuel efficiency by design innovations and introductions of new hardware.Each W-DCT has its unique design and hardware.It demands the lubricant to provide excellent wet clutch friction performance and anti-shudder friction durability,good synchronizer friction performance and durability,high load-carrying ability,excellent bearing performance,strong anti-corrosion performance,high thermal and oxidative stability,excellent material compatibility,etc.Particularly,the requirement of the wet clutch friction performance in W-DCT is much more severe than conventional ATFs and CVTFs.We report here our latest W-DCTF technologies developed for different W-DCT applications.DCTF-1 was optimized for a two-sump W-DCT application with the clutch lining material of friction material A(FM-A).DCTF-1 shows high and stable dynamic friction,static friction,particularly,high quasi-static friction without any shudder tendency in GK tests.DCTF-2 was designed for a one-sump W-DCT application with the same clutch lining material of FM-A.DCTF-2 completes 42,000 cycles of the severe GTI chassis dynamometer vehicle test without any issues,which is comparable to the factory fill fluid DCTF-FF.DCTF-3 was developed for a one-sump W-DCT application with a different clutch lining material of FM-B.DCTF-3 shows high and stable dynamic friction in the severe newly developed SAE DCT test procedure.DCTF-3 also gives excellent LVFA durability of over 720 h in the JASO M349 test procedure on FM-B.

Dynamic Engaging Characteristics of Wet Clutch in Automatic Transmission

Wet clutch is an important shifting component in automatic transmission,and its properties will affect the gear shift performance. By comparing the calculated and test results,the static friction torque model was proved to be capable of describing the real pressure and torque only in the situation of high-energy engagement.Therefore,a dynamic torque model was proposed on basis of hydrodynamic properties between friction surfaces, in which the clutch engagement was divided into three phases for hydrodynamic lubrication, mixed lubrication, and mechanical contact. The proposed dynamic torque model was validated by comparing the calculated and test results. The effects of temperature,pressure,and pressure changing rate of automatic transmission fluid( ATF) on the clutch torque were analyzed. Based on these results,the clutchto-clutch torque control during shifting in automatic transmission was optimized,and as a result,the shifting comfort was significantly improved since the problems such as the fluctuation and sudden drop of the engine rotating speed during shifting were eliminated.

Design of Multi-domain Collaborative Simulation System for Dual Clutch Transmission Based on CAN Bus

A multi-domain collaborative simulation(MDCS) system for dual clutch transmission(DCT) was presented based on controller area network(CAN) bus.An interface card of CAN bus was designed,in which MDCS subsystems were linked as the nodes according to the interface mode of MDCS.A DCT simulation model was established based on Matlab/Simdriveline,whose running process was accurately controlled by the designed control system.The playback system of vehicle state(VPS) was proposed whose input was the road-test data,with a real vehicle test environment for the development of transmission control unit(TCU) being provided.A DCT kinematic system model was set up,and the running status of DCT parts could be displayed in real time.The functions of MDCS were verified based on the extra-urban driving cycle(EUDC) and the vehicle road-test data respectively.The results show the functions of MDCS are accomplished,and the unified supporting platform for the development of TCU is achieved by MDCS.

Combined-Type Continuous Variable Transmission with Quadric Crank Chains and One-Way Clutches

The conventional Continuously Variable Transmission （CVT） has been classified as belt-type or toroidal CVTs. Each CVT is fundamentally composed of several components to transmit the frictional force or torque generated by the driving force. Since the conventional CVTs use friction force, their energy （force or torque） transfer efficiency might be inferior due to slippage and pressure between the transmission components. Consequently, we propose a new type of structural CVT. The CVT we proposed in this paper means a combined-type transmission with quadric crank chains and one-way clutches.

Strategy to control crawling vehicles with automated mechanical transmission

In order to move vehicles with automated mechanical transmission （AMT） a little bit of distance, such as reversing into or moving in a garage, a control strategy for crawling vehicles was proposed. Based on the dynamic analysis of vehicle starting process and requirements of crawl driv- ing for the vehicle, a control strategy of the clutch was designed. The strategy increased the.slipping friction torque first and then decreased it, in order to realize the crawl driving. The speed increased by the engagement of the clutch, and then the clutch turned to disengage to the half disengage point, when the speed met the requirements. Based on the control strategy, a control software was de- signed. In the end, the software was tested on a vehicle with AMT. The lowest steady vehicle speed was reduced to 40% of the original value, which was set in the control strategy.

OPTIMAL TORQUE CONTROL STRATEGY FOR PARALLEL HYBRID ELECTRIC VEHICLE WITH AUTOMATIC MECHANICAL TRANSMISSION

In parallel hybrid electrical vehicle （PHEV） equipped with automatic mechanical transmission （AMT）, the driving smoothness and the clutch abrasion are the primary considerations for powertrain control during gearshift and clutch operation. To improve these performance indexes of PHEV, a coordinated control system is proposed through the analyzing of HEV powertrain dynamic characteristics. Using the method of minimum principle, the input torque of transmission is optimized to improve the driving smoothness of vehicle. Using the methods of fuzzy logic and fuzzy-PID, the engaging speed of clutch and the throttle opening of engine are manipulated to ensure the smoothness of clutch engagement and reduce the abrasion of clutch friction plates. The motor provides the difference between the required input torque of transmission and the torque transmitted through clutch plates. Results of simulation and experiments show that the proposed control strategy performs better than the contrastive control system, the smoothness of driving and the abrasion of clutch can be improved simultaneously.

Review on development progress of automatic manual transmissions control

In recent years, the sustainable development of automatic manual transmissions (AMTs) control in vehicles is conspicuous. The control applications have grown fast and steadily due to the tremendous progress in power electronics components and the control software that enhance the requirements for delivering higher vehicles performance. AMTs control strategies achieve a reduction in the driveline dynamic oscillations behavior during gear shifting and clutch starting up processes. AMTs future expectations are an increase of torque capacity, more speed ratios and the development of advanced and efficient electronic control systems. This paper concerns with the progressing view of AMTs in the past, today and future, gives an overview of the potential dynamic problems concerned with AMTs and some control strategies used to solve those problems.

Optimal gear shift control strategy for positive independent mechanical split path transmission with automatic shift system

An improvement strategy which controls the shift effort and the power summing planetary gear set of steering clutches and brakes have been proposed based on the dynamic model of synchroniser in order to decrease the wear of synchroniser inserts, make gear shift easy and reduce the shock noise for a positive independent mechanical split path transmission which attached an auto- matic shift system when shifting. A kinetics model for the process of synchroniser engagement is built and analyzed in the paper. Thus for optimizing the gear shift process which is divided into three phases a model reference fuzzy self-adaption system is adopted. Through a 6 000 km road experiment, the control strategy has proved feasible and dependable.

The New Transmission for a Hybrid Car

The article deals an innovative device presented in the patent application PCT RU 2017000589, the mechanism for optimization of the work and coordination of the internal combustion engine with transfer of energy to the driving wheels. An original way of incorporating transmission elements through a differential to which the rotational energy is transmitted is proposed. When the engine energy is transmitted, the transmission ratio and torque are automatically adjusted, depending on the load on the output shaft.

汽车自动变速器换挡控制自动校准算法研究

为改善自动变速器的换挡特性,提出了一种基于模型的自动变速器离合器液压自动校准方法,实现离合器换挡参数的自动调整。该校准方法包括自动变速器仿真模型、车辆仿真分析算法和基于优化过程的自动校准算法,并在优化过程中进行迭代仿真和分析。以通电换挡为研究对象,仿真结果表明无论是通电升挡,还是通电降挡,该方法均能够有效地执行离合器液压曲线的基本映射,通过所提出的校准方法能够缩短实际车辆试验前的校准时间,提高自动变速器开发过程的效率。

Study of Controlling Clutch Engagement for AMT Based on Fuzzy Logic

The control of the clutch engagement for an automatic mechanical transmission in the process of a tracklayer getting to start is studied. The dynamic model of power transmission and automatic clutch system is developed. Using tools of Simulink, the transient characteristics during the vehicle starting, including the jerk and the clutch slip time, are provided here. Based on the analyses of the simulation results and driver’s experiences, a fuzzy controller is designed to control the clutch engagement. Simulation results verify its value.

考虑离合器摩擦性能衰减的湿式DCT车辆起步控制研究

建立了考虑离合器摩擦系数变化及离合器性能衰减的湿式双离合变速器(dual clutch transmission,DCT)车辆起步过程动力学模型,以车辆起步过程冲击度、滑摩功和起步滑摩时间为优化目标,采用线性二次型最优控制方法获得了车辆起步过程离合器最优传递转矩。针对离合器摩擦系数变化及离合器性能衰减对车辆起步过程离合器压力控制的影响,提出了一种离合器压力非线性鲁棒控制策略,以实现对离合器最优传递转矩的跟踪。结果表明,所提出的非线性鲁棒控制策略能够在离合器摩擦系数变化的情况下实现对离合器最优传递转矩的有效跟踪,跟踪误差不大于0.02 N·m,且能够适应摩擦性能衰减导致不同寿命阶段摩擦系数的不同变化规律,与比例-积分-微分(proportion-integral-differential,PID)控制策略相比具有更精确的控制效果和更强的鲁棒性。

一种变速箱离合器自动安装机构的设计

离合器是变速箱的重要核心组件,也生产装配工艺中重要的环节。本文介绍了离合器在变速箱装配生产线上实现自动装配的方法和自动装配机构的设计,该自动装配机构和工业机器人组合应用,利用PLC作为电气控制核心,采集外部信号,通过Profinet总线网络与机器人交互信息,实现对离合器的自动化装配。这个机构设备可以很好的解决离合器在安装时容易磕碰到输入轴齿和油泵斜齿轮的问题。对工厂来说,解决了人工装配中的难点痛点,也节省了成本,提升变速箱的装配质量和效率。从自动装配行业来说,未来发展趋势是向着无人的方向发展,为以后提高变速箱装配线的自动化水平提供参考。

双离合器变速箱换挡集成学习控制器设计及分析

为了提高车辆运行的稳定性,设计了一种双离合器DCT变速箱换挡集成学习控制器。基于预测模型建立MPC控制器,以补偿转矩保障转速精准追踪。研究结果表明,在0.11 s时DCT开始出现升挡转矩相,车速整体维持稳定变化的态势,车辆冲击度的最大值是4.8 m/s^(3),有利于大大提高换挡的稳定性。相比其他控制方法,基于经验知识MPC换挡方案获得更优的平顺性控制效果,滑摩功也发生降低,可以更快完成动力响应。该研究有助于提高汽车自动控制,为后续的换挡控制奠定理论基础。

大功率拖拉机湿式离合器液压系统特性分析

大功率拖拉机湿式离合器具有复杂、高阶、非线性强等特点,是动力换挡变速箱(Power Shift Transmission,PST)执行换挡动作的关键部件。首先,分析了大功率动力换挡拖拉机湿式离合器液压系统的组成和工作原理,然后,搭建了基于dSPCE的湿式离合器液压系统试验台,开展了湿式离合器液压系统特性试验,分析了比例减压阀和湿式离合器的稳态特性和动态特性。最后,通过改造离合器试验台,采集离合器活塞位移和离合器油压,掌握了PST湿式离合器的活塞位移行程和基本运动特性。研究成果可为离合器压力控制和换挡质量控制研究提供模型依据。

大功率拖拉机湿式离合器液压系统建模与验证

湿式离合器是动力换挡拖拉机执行换挡动作的关键部件,具有复杂、高阶、强非线性等特征。首先,通过分析大功率动力换挡拖拉机湿式离合器液压系统的结构与工作原理,建立了其数学模型;然后,基于MATLAB和AMESim搭建了系统仿真模型;最后,通过对比MATLAB与AMESim模型仿真结果,验证了所建数学模型的准确性。研究成果可为离合器压力控制及换挡品质控制研究提供模型基础。