Clutch Control for Automotive Start-up Process

The conventional driveline with manual gearbox and dry clutch can be retro-fitted to manipulate automatically,so that the electo-mechanical components or the Automated Mechanical Transmission has been obtained.The clutch engagement position for automotive start-up process can be controlled by the fast-low-fast speed.How to control the clutch engagement during the slipping stage is the key to clutch control.The mostly influent factors of the clutch engagement during start-up process have been analysed thoroughly from the practical point of view.The strategy of clutch control has been proposed on the principle of lessening the start-up jerk and the friction work.It is successfully applied to Santana model,which can be proved by the road test of the vehicle on the slope.     

联合油压控制的DCT升挡控制策略研究

针对某履带车辆的双离合器自动变速器(DCT)的升挡过程,对其进行动力学分析,建立各阶段动力学方程,总结分析传统升挡过程控制方法。基于传统方法的缺点提出基于双离合器联合油压控制的升挡控制策略,并运用Matlab/Simulink建立动力传动系统仿真模型。在升挡过程中,均通过比例控制高挡离合器的充油油压,分别运用传统控制方法与联合油压控制方法控制低挡离合器放油油压,对仿真结果进行对比分析。结果表明,联合油压升挡过程控制换挡平稳,防止了系统负转矩的产生,且滑摩功较小,提高了换挡品质。     

Performance and Slip Control of Torque Converter Lock-up Clutch

The application of lock-up clutch slip control balances the fuel economy and drivability, and greatly improves the performance of hydraulic automatic transmission. The structure of the lock-up clutch and the friction material of lock-up clutch lining are discussed, a detailed research on varying characteristic due to engaging time during the lock-up clutch engagement is developed, too. By applying the slip control, lower fuel consumption is achieved.     

Analysis of shifting control for dry dual clutch system

Aiming at the dry Dual Clutch Transmission (DCT) system, the motor driven dry dual clutch actuator is studied; the characteristic of distortion load for diaphragm spring and the dynamic transient process of the clutch are analyzed. The mathematical model is established for the system using fuzzy control and PI (Proportion Integration) control, and the simulation is carried out for the DCT shifting process. Simulation results indicate that the motor driven dry dual clutch system can meet the need of the shifting process control requirements and guarantee the high performance of DCT system.     

Simulation and Analysis of the Dual-Clutch Transmission Starting Control

With unique configuration characteristic,dual-clutch transmission(DCT)overcomes the shortcoming of power interruption when shifting in traditional AMT,which results in good power performance,fuel economy and driving comfort,and recently it becomes a new development trend in the field of transmission.Basing on the analysis of starting control principle of DCT,control principle and method that both the dual clutch engaged in the starting process simultaneously with engine constant speed are proposed.And the starting characteristic of the dry dual-clutch transmission is simulated and analyzed,providing theory foundation for the development and research of the dual-clutch transmission.     

Analysis on starting characteristic of continuously variable transmission system with reflux power

Considering on the characteristics of the transmission system and some key units of continuously variable transmission system with reflux power, a dynamic simulation model and a control strategy are established. The design method of the new continuously variable transmission system is verified by simulation. The simulation result on this continuously variable transmission system shows that the rotating speed of the driven plate can rise up rapidly during starting clutch engagement, and the sliding friction power is lower than 3 kJ which is nearly equal to one third of the friction power of the traditional vehicle.     

Analysis on braking control strategy of heavy vehicles with AMT

According to kinetic analysis, we put forward a braking control strategy under the down shift condition. When auxiliary engine brake torque affects the stability of vehicle, it should disconnect the clutch; and when auxiliary engine brake torque doesn’t affect the stability of vehicle, it should jointing the clutch. The speed acceleration, the braking time, and the braking distance are analyzed in while the clutch and joint the clutch are disconnect. The analysis indicates that when auxiliary engine brake torque doesn’t affect the stability of vehicle, jointing the clutch can reduce the braking time and distance obviously.     

Modeling and control system simulation of automobile DCT

In order to reduce development time and cost of dual clutch automated mechanical transmission(DCT) control system,the dynamic model of automobile DCT control system is established by Matlab/SimDriveLine and the engine model is improved by neural network.Based on Matlab/Simulink,the simulation models of DCT control during starting phase,shift phase and shift rule are set up,and then the whole system of DCT is simulated.The simulation result indicates that the DCT system dynamic model and the designed controller are reasonable and feasible,and proofs that the model is suitable for developing DCT control system and improves the design efficiency of DCT system.     

System Testing with the Measurement & Control Network Technology

with the measurement and control network technology, the research and development of the performance test system of silicone oil fan clutch for automobile are introduced. The system can take intelligent measurement with three clutches on the line simultaneously. It also can display measurement curves, file reporting, and so on in the same time. The system has the capability of 256 channels communications.     

Analysis of oil pressure distribution influenced by channel flow structure of wet friction clutch

When multi disk clutch is in disengaged operation, friction plates and mating plates may not separate absolutely. To avoid the slipping friction caused by this and reduce the clutch’s overheating, the lubricant pressure between the plates should be well distributed in design. With the use of ANSYS/FLOTRAN software, 3 D finite element models of six different channel flow structures are established. Using finite element method and the fluid dynamic theory, the flow field is analyzed, and then the law of the influence of different channel flow structures on oil pressure distribution between the plates is summarized. The result of the study shows that the four squirt holes at right side with perforated structure are better than those without, and squirt holes with the cone or stepped shape are better than those with column shape, which means that with the two improvements of the channel flow structure, the lubricant pressure distribution can be uniformed.     

Multifractal spectrum prediction of the running-in process of wet clutch

For predicting the running-in process of wet clutch test,a method based on multifractal spectrum and its parameters are proposed to predict the running-in state,combining with the geometry features of friction torque signal in test. Firstly,the concept of multifractal spectrum based on the box-counting method is introduced;and then the inherent relationship between the multifractal parameters and friction torque is discussed;finally,friction torque signals from a certain type wet clutch running-in test are analyzed and depicted by the multifractal spectrum and its parameters. The analytical results show that the geometry features of friction torque signals can be quantitatively described through multifractal spectrum and its parameters,and the breadth and fractal dimension difference of maximum-minimum probability subset of multifractal spectrum gradually decrease with the running-in process,while the minimum singularity exponent increases gradually with the running-in process. Therefore the running-in state of wet clutch can be effectively predicted by the multifractal spectrum of friction torque in test.     

Optimum Design of New-style Impulse Variable Speed Device Based on Invariable Impulse Value

The impulse value of a impulse mechanism has a notable influence on the dynamics capability of impulse variable speed device. Basing on this point, the authors take crank-rocker mechanism in series with slider-crank mechanism as impulse mechanism when we design the impulse variable speed device. The link used to adjust the speed is applied in slider-crank mechanism which has no quick-return characteristic, so the advance-to return-time ratio keeps stable when we adjust its speed. The speed fluctuation also keeps invariable. The new method overcome the default that this kind of impulse variable speed device has a notable speed fluctuation. At the same time, ADAMS software is used to optimize and show the real motion law. From the simulation result we can get the speed fluctuation is down to 18% in the whole process. The change of speed fluctuation is down to 1%. The result is better than other mechanism like this category.     

Analysis on the influence of friction coefficient on the starting control of automatic mechanical transmission

Based on the fact that friction coefficient changes with the friction surface temperature,the influence of friction coefficient on automatic mechanical transmission (AMT) is studied during repeated starting process. A model is established for the transmitted torque of clutch and the temperature rise on clutch plate surface during AMT starting. Based on the launching control rule of “fast-slow-fast”,the repeated starting for AMT and the friction work of the friction pair are simulated. The simulation results show that friction coefficient changes with the change of the friction work. After several starting,friction coefficient and the transmitted torque of clutch diminish a lot,and the slipping between drive plate and clutch plate always exist, therefore,the vehicle can’t start.     

Thermo-mechanical coupling analysis of dual-steel-disc of wet multi-disk clutch

To solve the failure problem of power transmission caused by warping, crackle on dual-steel-disc of wet multi-disk clutch, a shipborne wet multi-disk clutch is taken as a research object, models of generation and distribution of friction heat flux are built and numerical methods to solve temperature field and coupled stress field are put forward. Research methods of thermo-mechanical coupling problem of wet multi-disk clutch are proposed. The thermo-mechanical coupling phenomenon of dual-steel-disc is investigated, and the failure mechanism of dual-steel-disc of wet multi-disk clutch is revealed. In the engagement process, the results of temperature field show that the temperature of the dual-steel-disc gradually increases from the inner edge to the outer edge, and the temperature of friction surface reaches the highest at 2.6 s in the 3-second-engagement. The rules of thermal stress distribution are attained that the circumferential tensile thermal stress appears in the region close to the inner edge, while the radial tensile thermal stress appears in the region close to the outer edge. The theoretical basis to solve the thermal failure problem of dual-steel-disc of wet multi-disk clutch is provided.     

仓库鼠类综合防治技术的研究

对广东省５个单位的仓库鼠类进行了调查，结果表明，主要为褐家鼠（６２．９％～８２．４％）和小家鼠（１７．７％～３７．６％），根据鼠类特性，从控制鼠类密度改变鼠类行为，用化学和物理方法，以及仓房设施改造等方面着手，进行防治仓库鼠类的试验研究。     

Complex Correlation System Control Based on Human Simulation Intelligence

Because there are lots of difficulties in mathematic modeling for uncertainty complex object, so it is not suitable to utilize traditional methods in some aspect such as identification, analysis, synthetical design and implementation. Especially, for the idea of system modeling, it is very different in comparison with traditional mathematic modeling, therefore, it is very difficult to study control problem for uncertainty system in technology and theory. On the basis of summarizing characteristics of uncertainty complex object, present to establish generalized control model, and apply intelligent control strategy to implement control effectively. In addition, authors also studied control algorithm and system structure. Engineering practice shows that it is effective and successful to establish generalized control model, and select intelligent control strategy for uncertainty control system.     

Controlling Model of Company''s Financial Index

In a mature, standard and perfect securities market, with the interaction relationship each financial data, we build a model of a union equation. In terms of the data of years data, we can estimate the parameters of the theory of financial control, the managers and investors can control reasonably the process to the object of financial measures system, through some relevant financial measures data. In the opposite, they also can calculate the financial measures data of the firm by the optimum controllable variable.