Intelligent Correction of Shift Schedule for Dual Clutch Transmissions Based on Different Driving Conditions

This paper focuses on intelligent correction of shift schedule for dual clutch transmissions based on different driving conditions. The problem of standard shift schedule has been presented, and the strategy has also been proposed to avoid shift hunting and unexpected shift. The driver’s intention and driving environment have been unified recognized as different driving conditions. A fuzzy logic technology has been used in driver’s attention recognition based on the throttle opening and its derivative. The standard shift schedule has been intelligently corrected at different driving condition separately. An algorithm based on correction coefficient of throttle opening and vehicle speed is proposed for intelligent correction. The corrected shift schedule can be directly used in real time shift control with suitable correction coefficient.

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Development of a new sub-shift schedule and control algorithm for a hydro-mechanical transmission

Advances in Mechanical Engineering ◽

10.1177/1687814016682435 ◽

2016 ◽

Vol 8 (12) ◽

pp. 168781401668243 ◽

Cited By ~ 1

Author(s):

Sunghyun Ahn ◽

Jingyu Choi ◽

Hanho Son ◽

Suchul Kim ◽

Jinwoong Lee ◽

...

Keyword(s):

Control Algorithm ◽

Peak Torque ◽

Speed Ratio ◽

Mechanical Transmission ◽

Vehicle Speed ◽

Shift Schedule ◽

Shift Control ◽

Wheel Torque ◽

Simulation And Experiment ◽

And Control

In this study, a new sub-shift schedule was proposed for a hydro-mechanical transmission. To develop the sub-shift schedule, a network analysis was performed by considering the hydrostatic unit loss and mechanical component losses. In the new sub-shift schedule, the sub-shift gear can be selected with respect to the demanded wheel torque and vehicle speed, which provides improved system efficiency for the given vehicle operating condition. Since the sub-shift can only be carried out at a speed ratio where the off-going and on-coming clutch speeds are synchronized in the existing sub-shift control, a sub-shift control algorithm without the clutch speed synchronization was proposed to apply the new sub-shift schedule using the forward clutch pressure and hydrostatic unit stroke control. The performance of the sub-shift control algorithm without the clutch speed synchronization was evaluated by the simulation and experiment. It was found from the simulation and experimental results that the sub-shift can be achieved, showing an acceptable peak-to-peak torque variation in the driveshaft.

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A novel multi-parameter coordinated shift control strategy for an automated manual transmission based on fuzzy inference

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407016662579 ◽

2016 ◽

Vol 231 (5) ◽

pp. 684-699 ◽

Cited By ~ 5

Author(s):

Lipeng Zhang ◽

Xiaohong Zhang ◽

Zongqi Han ◽

Junyun Chen ◽

Jingchao Liu

Keyword(s):

Control Strategy ◽

Dynamic Performance ◽

Automatic Transmission ◽

Rate Of Change ◽

Manual Transmission ◽

Vehicle Speed ◽

Shift Control ◽

Automated Manual Transmission ◽

Shift Strategy ◽

Driver’S Intention

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.

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Research for Cornering Gearshift Strategy of Automatic Transmission Vehicles Based on Fuzzy Inference

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.336-338.1234 ◽

2013 ◽

Vol 336-338 ◽

pp. 1234-1240

Author(s):

Yao Fu ◽

Wen Ge Zhang ◽

Yu Long Lei ◽

Hong Bo Liu

Keyword(s):

Real Time ◽

External Load ◽

Fuzzy Inference ◽

Automatic Transmission ◽

Lateral Acceleration ◽

Vehicle Speed ◽

Test Results ◽

Variation Rate ◽

Driving Condition ◽

Shift Frequency

Undesired gearshift often occurred when the vehicle was under the curve driving condition. To resolve this problem, this paper proposed a fuzzy correction gearshift strategy under cornering which put the lateral acceleration and lateral acceleration variation rate, the external load and the real-time vehicle speed as parameters. Road test results showed that the undesired gear shift frequency was largely reduced and this method improved driving comfort and security under cornering condition.

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Prediction of Tread Pattern Wear by an Explicit Finite Element Model3

Tire Science and Technology ◽

10.2346/1.2804913 ◽

2007 ◽

Vol 35 (4) ◽

pp. 276-299 ◽

Cited By ~ 18

Author(s):

J. C. Cho ◽

B. C. Jung

Keyword(s):

Finite Element ◽

Wear Rate ◽

Tangential Stress ◽

Rate Equation ◽

Constitutive Equations ◽

Slip Velocity ◽

Test Results ◽

Explicit Finite Element ◽

Driving Condition ◽

Driving Conditions

Abstract Tread pattern wear is predicted by using an explicit finite element model (FEM) and compared with the indoor drum test results under a set of actual driving conditions. One pattern is used to determine the wear rate equation, which is composed of slip velocity and tangential stress under a single driving condition. Two other patterns with the same size (225/45ZR17) and profile are used to be simulated and compared with the indoor wear test results under the actual driving conditions. As a study on the rubber wear rate equation, trial wear rates are assumed by several constitutive equations and each trial wear rate is integrated along time to yield the total accumulated wear under a selected single cornering condition. The trial constitutive equations are defined by independently varying each exponent of slip velocity and tangential stress. The integrated results are compared with the indoor test results, and the best matching constitutive equation for wear is selected for the following wear simulation of two other patterns under actual driving conditions. Tens of thousands of driving conditions of a tire are categorized into a small number of simplified conditions by a suggested simplification procedure which considers the driving condition frequency and weighting function. Both of these simplified conditions and the original actual conditions are tested on the indoor drum test machines. The two results can be regarded to be in good agreement if the deviation that exists in the data is mainly due to the difference in the test velocity. Therefore, the simplification procedure is justified. By applying the selected wear rate equation and the simplified driving conditions to the explicit FEM simulation, the simulated wear results for the two patterns show good match with the actual indoor wear results.

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