Research on Shift Control Strategy in Braking Conditions of Automatic Transmission Vehicles based on Fuzzy Inference

2014 ◽  
Author(s):  
Yao Fu ◽  
Yulong Lei ◽  
Ke Liu ◽  
Yuanxia Zhang ◽  
Huabing Zeng
Author(s):  
Lipeng Zhang ◽  
Xiaohong Zhang ◽  
Zongqi Han ◽  
Junyun Chen ◽  
Jingchao Liu

For a vehicle equipped with an automatic transmission, the shift control strategy should reflect the driver’s intention in the dynamic performance and the economy performance of the vehicle. However, the driver’s intention is difficult to identify and involve in the shift strategy because of the complexity of driving environments, the diversity of powertrain parameters and the randomness of the driver’s behaviour. Therefore, in this paper, by considering a vehicle equipped with an automated manual transmission as the study object, a novel multi-parameter coordinated shift control strategy is proposed on the basis of identification of the driver’s intention. First, in order to predict the intention of the driver more effectively, the relative opening degree of the accelerator is defined on the basis of the dynamic analysis. Then, the characteristics of the driver’s expected acceleration, which involve the influence of the driving environment, are proposed. They can be classified into five categories, namely stop, deceleration, keep, acceleration and urgent acceleration. Next, a fuzzy control system is designed to identify the driver’s acceleration characteristics in real time. This considers the vehicle speed, the rate of change in the opening degree of the accelerator and the relative opening degree of the accelerator as the inputs and the quantitative intention of the driver as the output. Finally, the novel multi-parameter coordinated shift control strategy is formulated on the basis of the vehicle speed, the opening degree of the accelerator and the quantitative intention of the driver. The designed shift strategy is compared with conventional methods using simulations and is verified by road tests. The results show that the shift control strategy can make the vehicle shift much more effective.


2016 ◽  
Vol 835 ◽  
pp. 687-692 ◽  
Author(s):  
Lin Yue Zhang ◽  
Yao Fu ◽  
Xing Zhong Li

Shift process of automatic transmission is divided into torque phases and inertia phase, and the control principle of clutch to clutch shift is studied with the lever method. Then, inertia phase engine and transmission integrated control principle and entire shift process engine and transmission integrated control principle are respectively studied with taking power on up shift as study example and taking the transmission output torque fluctuations during shifting minimum as control target. Simulation results are compared to the results of power on up shift without engine and transmission integrated control, and it is proved that the transmission output torque overshoot peak with inertia phase engine and transmission integrated control strategy is decreased significantly and shifting jerks are reduced. Shift quality is improved significantly.


Author(s):  
Xiaohua Zeng ◽  
Zhenwei Wang ◽  
Dafeng Song ◽  
Dongpo Yang

The coordination control of a transmission system has gradually attracted more attention with the development of hybrid electric vehicles. However, nonlinear coupling of multiple power sources, superposition of different dynamic characteristics in multiple components, and withdrawal and intervention for a power-split powertrain with a two-speed automated manual transmission (AMT) gearbox can cause jerk and vibration of the transmission system during the shift, which has higher requirements and challenges for the overall performance improvement of the system. This paper designs a novel, robust, augmented H∞ shift control strategy for a power-split system with a two-speed AMT gearbox of a heavy commercial vehicle and verifies the strategy’s effectiveness with simulations and experiments. First, the dynamic plant model and kinetic equations are established, and the shift is divided into five stages to clearly reveal the jerk and vibration problem. Based on augmented theory, a robust H∞ shift control strategy is proposed. Shift coordination is transformed into a speed tracking problem, and state variable and disturbance are reconstructed to obtain a new augmented system. Simulation and hardware-in-the-loop test are carried out to verify the effectiveness of the strategy, which mainly includes simulation of pneumatic actuator and H∞ control strategy. Results show that the proposed H∞ control strategy can greatly reduce the jerk of the transmission system. The jerk produced by the proposed strategy is decreased from 20.4 to 4.07 m/s3, leading to a substantial improvement of 80%. Therefore, the proposed strategy may offer a theoretical reference for the actual vehicle controller during the shift.


2010 ◽  
Vol 156-157 ◽  
pp. 137-141 ◽  
Author(s):  
Hui Xian Han ◽  
Pi Shun Ren ◽  
Xian Li Cao ◽  
Mao Fu Liu

This study analysis the use requirement of engineering vehicles travel system, introduces the hydraulic system and the design scheme of automatic transmission system, discusses the control strategy and method of engineering vehicles travel speed, modeling and simulating based on the actual system software and hardware and the control Strategy and method of automatic transmission system, verifies the vehicle control effect through virtual test, and draws the full-text conclusion at last.


2021 ◽  
Vol 37 (4) ◽  
pp. 677-689
Author(s):  
Guang Xia ◽  
Yueqiang Wang ◽  
Xiwen Tang ◽  
Linfeng Zhao ◽  
Jinfang Hu

Highlights A power shift control strategy based on torque and speed transition, which aims to deliver multiple target and multiparameter optimization of power shift control, is proposed in this study. It can effectively solve the shift power cycle. Based on minimum optimal control theory, the optimal control of shift quality during power shifting optimizes clutch terminal oil pressure, which is determined by solving the Rebecca differential matrix equation and shift characteristics based on various stages. By aiming at the multiple target and multiparameter optimization problem of the clutch control in the power shift process, the minimum optimal control principle is applied to the shift quality optimization of the power shift. Based on the minimum optimal control theory, the optimal solution of the terminal oil pressure of the clutch is determined by solving the Rebecca differential matrix equation to improve the shift quality of the power shift process. Abstract . The dual clutch of the combined transmission of a tractor with large horsepower uses a dynamic shifting process, in which only one clutch undergoes slipping friction during the shift. A power shift control strategy based on torque and speed transition, which aims to deliver multiple target and multiparameter optimization of power shift control, is proposed in this study. Based on minimum optimal control theory, the optimal control of shift quality during power shifting optimizes clutch terminal oil pressure, which is determined by solving the Rebecca differential matrix equation and shift characteristics based on various stages. In addition, the power shift simulation model of the double clutch is established. Simulation results show that the power shift control strategy based on single slip friction can effectively avoid power flow cycle, uninterruptible tractor power shift, and adaptive resistance change. The minimum optimization theory can effectively reduce the output torque fluctuation in the dynamic shift process, reduce friction work, and improve the shift impact. Keywords: Double clutch, Heavy-horsepower tractor, Minimum theory, Power shift.


Sign in / Sign up

Export Citation Format

Share Document