A study of shift control using the clutch pressure pattern in automatic transmission

2003 ◽  
Vol 217 (4) ◽  
pp. 289-298 ◽  
Author(s):  
Woosung Han ◽  
Seung-Jong Yi
Keyword(s):  
Dynamic Models ◽  
Equations Of Motion ◽  
Automatic Transmission ◽  
Torque Converter ◽  
Optimum Pressure ◽  
Planetary Gears ◽  
Transient Characteristics ◽  
Engine Torque ◽  
Shift Control ◽  
Road Load

It is necessary to understand the overall system including engine, torque converter, multiplate clutch, band brake, one-way clutch, planetary gears, road load and tyre to analyse the performance of the vehicle powertrain. The performance of the powertrain can be analysed using dynamic models including transient characteristics and the equations of motion are derived from the dynamic models of the powertrain. In this study, the shift transient characteristics of the vehicle equipped with a Ravigneaux-type planetary gears automatic transmission has been investigated. A shift control using engine torque reduction and optimum pressure trajectory has also been investigated in order to enhance transient characteristics during shift.

Torsional Vibration Analysis of a Hydrodynamic Split Torque Transmission

1967 ◽  
Vol 89 (4) ◽  
pp. 605-610
Author(s):  
D. A. Klokkenga
Keyword(s):  
Experimental Data ◽  
Torsional Vibration ◽  
Vibration Analysis ◽  
Equations Of Motion ◽  
Planetary Gear ◽  
Torque Converter ◽  
Transmission System ◽  
Engine Torque ◽  
Lagrange’S Equation ◽  
Torque Transmission

The steady-state torsional vibration for one mode of an engine transmission system was analyzed, and the analysis was verified by experimental data. The engine transmission system included a diesel engine, torque divider which consisted of a fixed housing, single-stage torque converter and a planetary gear set, and a dynamometer. The equations of motion are derived by an energy method (LaGrange’s equation) and a numerical solution of these equations is obtained with the aid of a digital computer. The analytical and experimental results agree when empirical values for torque converter damping are used.

Analysis of Improving Automatic Transmission Upshift Performance by Using Off-Going Clutch During Inertia Phase

2021 ◽  
Author(s):  
Ivan Cvok ◽  
Vanja Ranogajec ◽  
Josko Deur ◽  
Yijing Zhang ◽  
Vladimir Ivanovic ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
Trajectory Optimization ◽  
Piecewise Linear ◽  
Phase 1 ◽  
Automatic Transmission ◽  
Single Step ◽  
Dissipated Energy ◽  
Engine Torque ◽  
Shift Control ◽  
Clutch Control

Abstract The paper presents a detailed numerical and algebraic analysis of potential for improving the step ratio automatic transmission (AT) upshift performance by means of modulating the off-going clutch during the inertia phase. The numerical analysis is based on Pareto optimal frontiers obtained by using the previously developed methods for AT shift control trajectory optimization and piecewise-linear control profile parameter optimization, where the control objectives include minimization of shift time, vehicle RMS jerk, and clutch dissipated energy. The analysis concerns the following control scenarios related to inertia phase: 1) oncoming clutch control only, 2) combined action of oncoming and off-going clutch; 3) oncoming clutch control extended with engine torque reduction control, and 4) combining all three control actions. The numerical results relate to an advanced 10-speed AT and various single-step and double-step upshifts, with emphasis on 1-3 shift. The numerical analysis results are proven algebraically based on a simplified AT model represented in bond graph form. The presented analysis shows that the off-going clutch can reduce either shift time or RMS jerk index by introducing power recirculation via the two clutches, which is in turn paid for by certain increase of AT energy loss.

A Systematic Approach for Dynamic Analysis of Vehicles With Eight or More Speed Automatic Transmission

2014 ◽  
Vol 136 (5) ◽  
Author(s):  
Sangchul Lee ◽  
Yi Zhang ◽  
Dohoy Jung ◽  
Byungchan Lee
Keyword(s):  
Dynamic Behavior ◽  
Test Data ◽  
Performance Metrics ◽  
Automatic Transmission ◽  
Control Unit ◽  
Torque Converter ◽  
Fine Tuning ◽  
Transmission Control ◽  
Engine Torque ◽  
Shift Quality

In this study, a dynamic model of a vehicle with eight or more speed automatic transmission (A/T) has been developed for the analysis of shift quality and dynamic behavior of the vehicle during shift events. Subsystem models for engine, torque converter, automatic transmission, drivetrain, transmission control unit (TCU), and vehicle are developed and integrated with signal information interface. The subsystems included in the model were carefully selected to improve the accuracy of the model by comparing the simulation results with the test data. The systematic modeling approach based on matrix operation proposed in the study enables calibrating and fine-tuning the transmission control unit for shift quality in a virtual vehicle environment. The model presented in the study is validated with the vehicle test data and the comparison shows very good agreement. This paper presents a generalized modeling methodology for multiratio automatic transmissions that require both direct and indirect shifts. The model developed in the study provides a valuable analytical tool for the calibration and tuning of the transmission control unit by allowing quantitative analysis on the dynamic behavior and the performance metrics of an automatic transmission.

Dynamics Equations of Planetary Gear Sets for Shift Quality by Lagrange Method

2008 ◽  
Author(s):  
Patinya Samanuhut ◽  
Atilla Dogan
Keyword(s):  
Equations Of Motion ◽  
Planetary Gear ◽  
Torque Converter ◽  
Vehicle Model ◽  
Lagrange Method ◽  
Engine Torque ◽  
Shift Quality ◽  
Planetary Gear Sets ◽  
And Shifts ◽  
Single Set

The equations of motion of planetary gear sets including pinion dynamics are derived using the Lagrange method. The Lagrange method provides a systematic procedure for derivation and yields a single set of equations that are valid for all gears and shifts for a given configuration. This procedure is applied to the coupled planetary gear set in GM Hydramatic 440 transmission. The planetary gear set equations along with a simplified engine, torque converter, friction elements and vehicle model are simulated for 2–3 and 3–4 shifts. The simulation results demonstrate that the equations derived for planetary gear sets can be used for studying shift quality.

Torque Converter Stress Analysis by Transient FSI Technique

2011 ◽  
Author(s):  
Takeshi Yamaguchi ◽  
Akihiko Okumura
Keyword(s):  
Automatic Transmission ◽  
Deformation Mode ◽  
Torque Converter ◽  
Previous Method ◽  
Hydrodynamic Performance ◽  
Element Analysis ◽  
Engine Torque ◽  
The Core ◽  
Computational Fluid Dynamics Cfd ◽  
Blade Model

The performance of a torque converter has been one of the most important areas of improvement for an automatic-transmission equipped automobile. Improving the torque converter’s performance and efficiency is key to saving fuel consumption, which is an important consideration with recent environmental awareness. Moreover, improving the overall automobile performance has led to more compact and lightweight transmissions. With the growing space constraints, the evolution of the torque converter has been towards smaller and more elliptical shapes. Since the smaller blades within the torque converter still have to endure the same engine torque, more strength is required of each blade of the pump, the turbine and the stator. There has been much research carried out to predict hydrodynamic performance and to understand the flow field inside a torque converter either experimentally or analytically using Computational Fluid Dynamics (CFD). However, none of the research has focused on the strength of the torque converter components — the blade, the shell and the core. The previous method for evaluating the blade strength had been to apply a simple, centrifugal pressure load on the blade using Finite Element Analysis (FEA). This method is no longer adequate for predicting blade stress since the pressure distribution on the blade is now known from CFD results. In this work, the fluid-structure interaction (FSI) technique is used to determine the deformation, which is indicative of the stress level of the blade, the shell and the core. In addition, this research compares the computational results from a model containing all blades to a conventional model of a single blade with axial symmetry. Analysis of the model containing all blades shows a completely different deformation mode than the single-blade model, especially for the pump blade. The differing results suggest that using a single-blade model analysis is less accurate for examining the torque converter structure.

Dynamic Temperature Testing and Modeling for an Automatic Transmission Clutch

2001 ◽  
Author(s):  
Thomas DeMurry ◽  
Yanying Wang
Keyword(s):  
Experimental Data ◽  
Real Time ◽  
Automatic Transmission ◽  
Thermal Characteristics ◽  
Torque Converter ◽  
Telemetry System ◽  
Temperature Model ◽  
And Control ◽  
Good Agreement ◽  
Dynamometer Test

Abstract The primary objectives of this study are (1) to validate the hardware design and control methodologies for preserving the thermo-mechanical integrity of a launch clutch emulating a torque converter and (2) to develop a simple, control oriented clutch-temperature model that may act as a virtual thermocouple in the processor of an automobile for real-time clutch-temperature predictions. In a dynamometer test cell, a Ford CD4E transaxle is instrumented with a thermocouple-based telemetry system to investigate clutch thermal characteristics during engagements, neutral idle, single and repeated launching, torsional isolation, and hill holding. A nonlinear, SIMULINK™-based model for estimating temperature is developed. The results from the simulations are in good agreement with the experimental data.

Optimal Design of Vibration Absorber Systems Supported by Elastic Base

1991 ◽  
Author(s):  
Hashem Ashrafiuon
Keyword(s):  
Dynamic Models ◽  
Damping Ratio ◽  
Equations Of Motion ◽  
Elastic Base ◽  
Design Parameters ◽  
Primary System ◽  
Vibration Absorbers ◽  
Equivalent Damping ◽  
System Equations ◽  
Different Levels

Abstract This paper presents the effect of foundation flexibility on the optimum design of vibration absorbers. Flexibility of the base is incorporated into the absorber system equations of motion through an equivalent damping ratio and stiffness value in the direction of motion at the connection point. The optimum values of the uncoupled natural frequency and damping ratio of the absorber are determined over a range of excitation frequencies and the primary system damping ratio. The design parameters are computed and compared for the rigid, static, and dynamic models of the base as well as different levels of base flexibility.

scholarly journals Smooth Gear Shift Control System of Automatic Transmission Using Estimated Output Shaft Torque.

1995 ◽  
Vol 61 (591) ◽  
pp. 4334-4338
Author(s):  
Toshimichi Minowa ◽  
Hiroshi Kimura ◽  
Junichi Ishii ◽  
Masahiko Ibamoto
Keyword(s):  
Control System ◽  
Automatic Transmission ◽  
Output Shaft ◽  
Gear Shift ◽  
Shift Control ◽  
Shaft Torque

scholarly journals Tracking control and robustness study of shifting process

2018 ◽  
Vol 46 (2) ◽  
pp. 99-106
Author(s):  
Xin-xin Zhao ◽  
Chao Guan
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Tracking Control ◽  
Pid Controller ◽  
Automatic Transmission ◽  
Good Control ◽  
Simulation Software ◽  
Control Effect ◽  
Engine Torque ◽  
Shift Quality

Heavy dump vehicles are usually working with big load changes and bad work environment, thus change the friction performance of transmission clutches, as well as great affect the shift quality seriously, which influence the vehicle performance. Many researchers developed a lot to design a useful automatic transmission control system. Using PID tracking control and Monte Carlo method, the controller based on an dynamic model was set up to analyze the shifting process of automatic transmission and its robustness in this paper．The shift process was divided into four stages, low-gear phase, torque phase, inertia phase and high-gear phase. The model presents the process from the first gear to the second gear when the torque has big change．Since the jerk and the friction work of clutch are both related to the speed of clutch which was easier to control, it was chose as the target to control the oil pressure for satisfying the requirement of shift quality．The simulation software, Maplesim and Simulink, were used to build the vehicle model and shifting controller for simulation under different working conditions, and the maximum jerk was changed from 34 m/s3 to 12 m/s3 after the optimization. In this paper the Monte Carlo has been used to quantize and evaluate the robustness of the closed-loop system for the friction coefficients and output torque of turbine variation leading by the friction feature parameters and throttle angle changed. Monte Carlo method was used to analyze the effectiveness and robustness of PID controller, which proves that it has good control effect when the throttle is ongoing minor fluctuations. When the throttle is full opening, a quadratic optimal controller based on disturbance is designed by the method of multi-objective optimization. When it changes within 20 percent, PID controller was designed under the guidance of tracking thoughts. The results also show that the controller could still obtain better effect when the friction coefficient ranged from -40 % to 40 % as well as engine torque changed from -20 % to 20 %, which indicates the robustness of controller.

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