Automatic Transmission Research Articles

Intelligent Gear Decision Method for Vehicle Automatic Transmission System Based on Data Mining

The gear decision logic of automatic transmission directly affects the vehicle's dynamic, fuel economic, and comfort performance. This study employs data mining techniques to address the issues of low adaptability and low recognition rate in the intelligent gear decision of vehicle automatic transmission systems. The research further proposes the utilization of Kalman filter, Hidden Markov Models, and Long Short-Term Memory networks for condition feature recognition and time series classification. Subsequently, dynamic programming algorithms are employed to optimize intelligent gear decisions. Combining driver intent and driving environment, an intelligent gear decision method is formulated. The results indicate that, during a 430s driving segment, the intelligent gear decision method consumes only 464mL of fuel, closely resembling the economic strategy's 457mL, with a gear shift frequency of 53, significantly better than the 79 shifts in the economic strategy. Moreover, the error rate for slope condition recognition is only 0.062%. In a 200s coupled condition, the intelligent gear decision results in fuel consumption of 207mL, approximating the actual vehicle's 219mL, while power-shifting consumes 316mL, and economic shifting only 202mL. This study not only improves the accuracy of gear decisions but also effectively enhances vehicle operational efficiency, providing valuable insights for future automatic transmission systems with significant practical value.

End-to-End Intelligent Fault Diagnosis of Transmission Bearings in Electric Vehicles Based on CNN

Environmental noise and transmission components can cause significant interference in vibration signals, rendering the extraction of bearing fault features challenging in service scenarios. Traditional fault diagnosis methods rely heavily on professional domain knowledge, prior models, and signal preprocessing methods. The accuracy of fault diagnosis depends on the quality of the fault-sensitive features extracted by vibration signal preprocessing methods. An improved convolutional neural network (CNN) end-to-end intelligent fault diagnosis model based on raw vibration data (RVDCNN) is proposed. The time-domain vibration signal of the transmission bearing is converted into a continuous two-dimensional numerical matrix, and a two-dimensional CNN model is constructed through network structure optimization. The original time-domain vibration signal numerical matrix of the bearing is trained and tested to extract and learn abstract fault features of different fault types, and then the fault classification of the bearing is achieved. To verify the generalizability of the RVDCNN intelligent fault diagnosis model, it is applied to the recognition of rolling bearings in the two-speed mechanical automatic transmission of electric vehicles, achieving recognition accuracy of 99.11% for seven types of bearings.

PELATIHAN PERAWATAN TRANSMISI MOTOR MATIC UNTUK MENINGKATKAN PERFORMA MOTOR DI DESA SUKAMUKTI

This service activity aims to train the community so that people can be more aware or given awareness about the maintenance of their personal vehicles, so that they are more independent in maintaining their motorbikes. Because many people only use their vehicles and don't think about maintenance, this will become a complex problem because over time, the vehicle's performance will decrease, and at any time this can have fatal consequences for the driver himself. From this problem, a solution was found by creating a motorbike maintenance training program to educate and introduce the procedures for maintaining motorbikes, especially in the automatic motorbike transmission section. The result of this activity is that residents understand more about the parts in automatic motorbike transmissions, how to maintain them, can practice the correct maintenance methods, and the dangers that arise if spare parts in automatic motorbike transmissions are not properly maintained.

Effect of Planetary Gear Set Designs on Thrust Bearing Power Loss in Automatic Transmission

Effect of Planetary Gear Set Designs on Thrust Bearing Power Loss in Automatic Transmission

Virtual Analysis and Optimization of Fuel Consumption for Diesel-Powered Buses

In this study, fuel consumption test cycles and commonly used SORT cycles for buses were discussed. An exemplary bus model was extensively modeled in terms of power systems. In ad-dition to main components such as the engine, transmission, torque converter, and axle, the drags of engine-powered components such as alternators, engine cooling fan, and air conditioning compressor were integrated into the powertrain model to ensure that the calculated consumption comes as close as possible to the real-life values. The tire model, which determines the quality standard in vehicle simulation, was also discussed in detail. During the modeling of these components, necessary parameters were obtained through analyses and tests conducted on the sample vehicle using the CAN bus and added sensors. After the completion of the model, real-life tests were conducted to validate the virtual analysis results. Once the model was validated, virtual studies continued to reduce the vehicle's consumption. Particularly during these studies, reducing consumption and enhancing performance through automatic transmission optimization were emphasized. When virtual models validated with SORT simulations are optimized with route-specific virtual analysis, public vehicles will minimize environmental impacts by reducing carbon emissions and at the same time perform more efficiently.

Dynamic modeling, clutch parameter adaptation, and control of automatic transmission for tracked vehicles

In this study, a novel TCU control structure and algorithms including also dynamic model of the transmission will perform the gear shifting of automatic transmissions used in tracked military vehicles are designed. In case of inherent wear of the clutches, the clutch parameters are estimated by means of an adaptation algorithm that uses only the information from the transmission input and output speed sensors. These estimated clutch parameters are used in clutch torque calculation is utilized by control algorithms. For the clutch speed control in the inertia phase, a PID control structure with a negative feedforward term that cancels the nonlinearities of the system is proposed. The feedforward term utilizes the estimated wear clutch coefficients in the calculation of friction coefficients. The parameters of the PID controller are optimized by a genetic algorithm. The designed all structure are firstly tested on a MATLAB/Simulink power train simulation model, and then tested using a unique transmission on a transmission dynamometer test bench to examine its suitability for real transmission scenarios. The performances of proposed PID control and a backstepping nonlinear controller that we constructed for the tracked vehicles are compared with and without clutch wear. Maximum tracking error is decreased by 98% with proposed adaptive PID control structure with nonlinear feedforward term compare to backstepping controller. In the case of clutch wear, the back-stepping control exists in the literature has been found to result in oscillation. By updating the estimated friction coefficient from adaptation algorithm, in the backstepping controller, it is concluded that these oscillations can be eliminated. Additionally, on-off solenoid valves, are widely used, are known to cause torque interruptions and jerks during gear shifting. It has been observed the control structure presented in this study reduced the jerks by one quarter.

Research on the efficiency analysis method of 9AT transmission planetary gear system based on power loss

As the core element of power transmission in Automatic Transmission (AT), the planetary gear system has advantages in the gear ratio range, load carrying capacity and transmission efficiency, and its transmission efficiency analysis is an important link in the design of automatic transmission.This paper proposes a method to analyze the transmission efficiency of planetary gear system of 9AT transmission considering power losses. Firstly, based on the hypergraph theory to establish the power transmission roadmap of each gear of the transmission (9AT) and the triangular hypergraph of the four-row planetary gear system, as well as the power flow model of the four-row planetary gear system without considering the power losses, and then the rotational speed, torque, and power change of each gear of the gear system are analyzed through the power spectrum. Secondly, a power flow model considering power losses and circulating power was established to analyze the influence law of different operating parameters (speed, torque, viscosity, gear meshing friction coefficient), and structural parameters (characteristic coefficients of each planetary row) on the transmission efficiency of the system. Finally, the equivalent planetary gear system transmission efficiency experimental bench considering losses is established to measure the transmission efficiency of the two-row planetary gear system at different speeds and torques, and the results of the experimental tests have the same trend with the theoretical calculations, which provides an analytical method to improve the transmission efficiency of the planetary gear system of the 9AT transmission.

Experimental Study of the Effect of Roller Shape Variations on the CVT System using Petrol-Pyrolytic Fuels toward the Power Characteristics of Automatic Motorcycles

There are two types of two-wheeled vehicles when viewed from the transmission system: manual and automatic. The automatic transmission circuit on the automatic motor, the roller (ballast), is on the primary pulley. In the market, various rollers (weights) are sold, starting from those that are standard and different from the standard with lighter or heavier weight variations. However, there are also aftermarket rollers produced in several automotive industries, one of which is UNIONMATERIAL. The difference lies in the shape and materials used. This study aims to analyze the effect of variations in the shape of the roller on the characteristics of power transmission on automatic motorcycles. The type of vehicle used is a motorcycle produced in 2009 using a dyno test test with two test methods. The first test is from low engine speed ± 1400-1600 rpm to 9000 rpm, while the second test is from medium engine speed ± 4000 rpm to 9000 rpm. In addition, the fuel consumption test was also carried out. The variation used is a roller shape consisting of a round roller, a sliding roller, and a flying roller weighing 12 grams. The highest results obtained at a power of 0.7 HP occurred on the flying roller with 7.1 HP/ 3916 rpm, while the torque was 5.19 N.m on the flying roller (23.96 N·m/1250 rpm). There is an effect on fuel consumption, but not too significant. The biggest difference occurred in the engine parameter RPM 5000 of 0.1 between the flying roller (0.9 L/h) and sliding roller (0.9 L/h) with the round roller (1 L/h) - this happens because the shape of the flying roller is not cylindrical and more dynamic, which is adapted to the movable drive face. There is an additional wing on the roller weight. The data from the results of this study have implications for increasing vehicle performance without changing engine capacity, which requires large costs.

Nonlinear dynamic characteristics analysis method of planetary gear train torsional vibration considering meshing oil film force

Planetary gear train is an important part of automatic transmission. The oil film between teeth is one of the key factors affecting the torsional vibration of planetary gear train. Selecting the appropriate oil film stiffness is of great significance for analyzing the nonlinear dynamic characteristics of planetary gear train. A method for analyzing the nonlinear dynamic characteristics of planetary gear system torsional vibration considering the oil film force between teeth is proposed in this paper. A 3-DOF torsional vibration model of planetary gear train considering oil film is established. In this model, the oil film between teeth is equivalent to a time-varying nonlinear spring-damper element, and nonlinear factors such as backlash and meshing error are also considered. The effects of meshing oil film thickness on oil film stiffness and damping are analyzed, and the torsional vibration characteristics of planetary gear train under different meshing stiffness, meshing damping ratio, and rotational speed are analyzed based on bifurcation diagrams. The results show that in one meshing cycle, the meshing oil film thickness first becomes larger and then becomes smaller. When the meshing oil film thickness increases, the meshing oil film stiffness and the equivalent meshing oil film damping become smaller. The torsional vibration of planetary gear train can be effectively reduced by increasing meshing stiffness, damping ratio, rotational speed within a certain range. This method provides technical support for reducing torsional vibration of planetary gear train and realizing stable transmission of planetary gear train.

On Dynamic Analysis and Prevention of Transmission Squawk in Wet Clutches

Abstract The genesis of clutch noise, encompassing squeaks, chatter, shudders, or judders, predominantly arises from friction-induced vibrations. As time progresses, the degradation of the clutch friction lining manifests due to diverse factors, such as the smearing of surface irregularities, elevated transmission fluid temperatures, fluctuating axial pressure, or aggressive shifting. Consequently, the slope of the friction curves tends to assume a negative gradient, giving rise to adverse damping effects like self-excited oscillations or stick-slip oscillations within the clutch pack. A lesser-discussed phenomenon, known as Squawking, occurs through analogous mechanisms discussed in this article. This article delves into investigating the occurrence of squawking noise observed in automatic transmission multi-disc clutches during low-speed up-shifts. The study discerns friction-induced vibrations as the primary contributor to squawk during the inertia phase of the clutch engagement cycle, a facet previously unidentified. During this phase, high-frequency weakly damped oscillating modes become self-excited due to the negative slope of the coefficient of friction versus slip speed curve. The coefficient of friction functions as negative damping during the inertia phase, where the energy dissipation from damping is insufficient to completely halt the oscillations, allowing them to persist at the natural frequency until clutch lock-up. Experimental data validates the proposed model and hypothesis, with results closely aligning with numerical simulations. The paper concludes by offering practical suggestions to prevent and mitigate squawk in automatic transmission wet clutches, with the aim of enhancing overall performance and reducing undesirable noise.

Examining drivers injury severity for manual and automatic transmission vehicles-involved crashes: Random parameter mixed logit model with heterogeneity in means and variances

The effect of vehicle transmission type on driver injury severities have not been thoroughly studied. The study used four-year historical crash data that occurred between the year 2019 and 2022 in Ghana. The data shows 1856 and 2272 crashes for automatic and manual transmission, respectively. The study examined the factors influencing driver injury severity in crashes involving vehicles with manual and automatic transmissions, using Random Parameter Mixed Logit Model to account for heterogeneity in the dataset. It was observed that use of manual transmission is related to a higher risk of incapacitating and fatal injuries compared to automatic transmission. Specifically, for automatic transmission vehicle-involved crashes, factors related to fatal injury were overaged vehicles, public transport, morning and evening peak hours, head-on and rollover crashes. Crashes involving saloon cars and low age cars were associated with incapacitating injury whiles rainy weather condition was related to both fatal and incapacitant injuries. Regarding manual transmission, fatal injury was associated with crashes involving male and novice drivers, cars, pickup trucks, HGV, public transports, morning and evening peak hours, rainy weather conditions and curved roads. Also, buses, private cars and trip distance were related to incapacitating injury. The rollover crashes and overaged vehicles were also associated with both fatal and incapacitating injuries. Four random parameters demonstrated heterogeneity in means, with two factors influencing the variances of two parameters for automatic transmission model. For the manual transmission model, five random parameters showed heterogeneity in means, with four variables influencing the variances of three parameters. These findings are valuable for policymakers, manufacturers, and drivers in implementing targeted interventions and safety measures to promote road safety.

Switching to a 100% remote follow-up of implantable cardiac electronic devices: Organizational model and results of a single center experience.

During the SARS-CoV-2 COVID-19 pandemic, the global health system needed to review important processes involved in daily routines such as outpatient activities within the hospital, including follow-up visits of implantable cardiac electronic devices (CIEDs) carried out in office. The aim of this study is to describe our 3.5 years of real-world experience of a full remote CIED follow-up, evaluate the success rate of remote transmissions, and verify the adopted organizational model. From April 2020 to November 2023, all patients with an activated and well-functioning remote monitoring (RM) system and automatic algorithms, like autocapture and autosensing, underwent exclusive RM follow-up. Unscheduled in-office visits were only prompted by remote yellow or red alerts. Patients were divided into two groups, based on available technology: Manual Transmission System (MTS) and Automatic Transmission System (ATS). The ATS group, in addition to ensuring a daily transmission of any yellow or red alerts, was checked at least every 15 days to ensure a valid connection. An automatic transmission was scheduled once a year, irrespective of alerts occurred. The MTS group provided a manual transmission every 6 months. One thousand nine hundred thirty-seven consecutive patients were included in the study. By the end of November 2023, a total of 1409 patients (1192 in the ATS and 217 in the MTS group) were still actively followed by our remote clinic (384 expired, 137 dismissed, 7 transferred). The overall success rate of transmissions with the adopted organizational model was 96.6% in the ATS group (connection index) and 87% in the MTS group. Conventional in-hospital follow-up visits decreased by 44%. Total clinic working time, resulting from the sum of the time spent during in-hospital and remote follow-up, after an initial increase, was progressively reduced to the actual -25%. Mortality rate for any cause was 7.5% per year in remote follow-up patients and 8.3% (p=NS) in in-office patients. In the ATS group, no device malfunctions were notified to our remote clinic, before we had already realized it through appropriate alerts. The available technology makes moving to a 100% remote clinic possible, without overwhelming clinic workflow, safely. Adopting an appropriate organizational model, it is possible to maintain high transmission success rates. The automatic transmissions allow a more frequent control of patients with CIED.

Pengaruh Variasi Spring Plat dan Massa Roller Terhadap Torsi dan FC Pada Motor 150 cc

In Indonesia, there are two types of motorcycle transmissions: manual and automatic. Users prefer automatic transmissions due to convenience and fuel efficiency. Automatic transmissions, such as CVT, CVT utilizes force for smooth and continuous gear ratio changes. CVT has disadvantages because unlike manual motors that have greater torque, especially on motorbikes that are three years old or more, such as poor acceleration at low to medium revolutions and wasteful fuel. This study aims to determine how the effect of adding spring plate and roller mass variations on torque and fuel consumption. This research uses a quantitative method with an experimental approach, by testing the independent variable to determine the results of the dependent variable. The result of this research is the use of lighter rollers can increase fuel consumption but the torque is getting smaller, because the use of lighter rollers has a fast rotation response so that the crankshaft in rotating the roller housing pulley is also lighter so it does not require a lot of fuel. While the use of heavier rollers coupled with spring plates also increases torque because the displacement ratio is faster, the torsional moment will be large which causes the torque to increase.

Підвищення ефективності забезпечення працездатності транспортних засобів

Accidental failures, leading to unplanned repairs, significantly increase the cost of their elimination compared to planned measures. A significant part of such failures are not sudden in nature. Gradual failure is preceded by a gradual change in some parameters. The impact of gradual failures on the efficient operation of road freight transport is increasing. Despite the fact that the failure of the engine, clutch or automatic transmission is not dangerous to the life and health of people, their impact on the economic condition of the enterprise is significant. There is a trend of decreasing the size of the rolling stock fleet for most of the country's motor transport enterprises. Therefore, the importance of keeping each car in working condition increases. To increase the accuracy of the prevention of gradual and sudden-gradual failures, a forecasting method based on the diagnosis of trucks with a specialized diagnostic car scanner TEXA Navigator MULTIHUB is proposed. The selection of diagnostic parameters was carried out in accordance with the requirements for compliance with the accuracy, efficiency, and informativeness of the diagnostic parameters. The research was carried out on MAN TG-X, MAN TGA, VOLVO FH 12, DAF 105 XF, and DAF 106 cars. A sequential cylinder shutdown test was conducted to determine the compression and efficiency of all cylinders. A gradual change in the operating parameter is determined based on the obtained decrease in revolutions. In the next test, the correction of the injectors for the amount of fuel injected into the cylinders is checked. The reference value is taken as 0. The correction tolerance for increasing or decreasing the fuel supply time should be within +1 or –1. Based on the received data, the nozzle is determined, in the correction gradually increases, which signals a problem with the nozzle's operation. For the clutch, a test of the position of the start of switching on and off was carried out. By reducing the percentage of idling, you can determine the gradual engagement of the clutch. All the conducted tests make it possible to graphically display a change in a parameter or property and, using extrapolation, to predict the moment of failure. All cars carry out freight transportation in international traffic. Control parameters and data extrapolation made it possible to predict engine, clutch, and automatic transmission failures. Selected diagnostic parameters can be used to predict and prevent failures.

Удосконалення методу оцінки програмного забезпечення контролю параметрів транспортних засобів

The purpose of the conducted research is to improve the method of evaluating the performance of the vehicle parameter control software. It is stated that a new technique for road transport in the field of monitoring its working condition is the creation of information systems for organizational and functional support of rolling stock operation processes with the help of information integration, namely the stages of the life cycle of rolling stock and systems for its technical control and diagnostics. It is shown that nowadays in road transport the basis of life cycle information support can be CALS or IPV/CALS/PLM - technologies (continuous support of the life cycle of vehicles), which are sometimes called product information support systems and are a part of intelligent transport systems. The analysis and clarification of the structure of the intelligent vehicle monitoring system was carried out on the example of the assessment of its environmental safety and its engine parameters. In the work, it is also planned to obtain experimental data from vehicle, the results of processing of which will allow to prove the existence of a real possibility of using the diagnostic complex on a modern automatic transmission system. It should be noted that the system for monitoring environmental safety indicators of vehicle, which is proposed by the authors, also contains in its composition the subsystem of intelligent processing of primary information, which can be used precisely in the role of "intelligent monitoring system". The data obtained and analyzed in the work indicate the need to also improve the efficiency of the neutralization of harmful substances in the engine warm-up mode, which can be implemented by reducing the engine warm-up time and more effective control of the injection/ignition process in transient modes, as well as by introducing an improvement algorithm of the control subsystem composition of the mixture precisely with feedback. The main diagnostic parameters of the vehicle engine during the start-up and warm-up processes, which affect the composition of harmful substances in the exhaust gases, were obtained experimentally. The proposed scheme for monitoring pollution of the roadside environment by traffic flows in the city.

Fault Identification of Direct-Shift Gearbox Using Variational Mode Decomposition and Convolutional Neural Network

The direct-shift gearbox is widely used in many applications, such as automotive and aerospace, due to its large transmission ratio and high transmission efficiency. Rough and heavy-duty working conditions induce various faults, such as scratches, fatigue cracks, pitting, and missing teeth due to breakage. These defects may lead to the failure of one or more components attached to an automatic transmission system. A fault identification scheme for the direct-shift gearbox has been developed, making use of variational mode decomposition (VMD) and convolutional neural network (CNN). The acquired raw signal from the gearbox under different health conditions (healthy, pitting, and chipping) is decomposed into different modes using VMD. The prominent mode is selected based on kurtosis, which is utilized to obtain scalograms. An image matrix is formed utilizing scalograms. Such matrices from different scalograms are divided into training and testing matrices. The training matrices train the CNN model, whereas the testing matrices validate the efficacy of the built CNN model. The proposed scheme identifies faults with 100% accuracy. The proposed scheme has also been compared with other neural networks. These results suggest that the proposed scheme outperforms other networks.

Optimizing Gear Ratios for Vehicle Performance Enhancement Using Taguchi Method

Gear ratio is a term used to describe the relationship between the number of teeth on two interlocking gears. It determines the speed and torque of a mechanical system, with higher gear ratios providing more torque but lower speed, while lower ratios offer higher speed but less torque. The study aims to design and develop a 1D vehicle physics model for powertrain matching and fuel economy prediction with the car's performance. For this study, the vehicle is modeled in GT-Suite to predict vehicle performance and fuel economy. The baseline results are compared with the actual testing data with the correlation of each parameter, performance, and fuel economy, which resulted in less than a 3% tolerance difference. The Taguchi method determines the optimal selection of gear ratios, while each gear ratio's significance toward the complete transmission set is calculated using ANOVA. The test subject for this research study is the Proton Saga 1.3L VVT, equipped with a 4-speed automatic transmission. The simulation results show an improvement of 3.36% for standing start acceleration and 3.18% for MDC fuel economy compared to the baseline model. Combining a 1D simulation cycle and statistical analysis approaches is a promising solution for optimizing system performance and fuel economy.

Pengaruh Perubahan Massa Roller dan Konstanta Pegas Sistem Cvt Terhadap Daya dan Torsi Pada Sepeda Motor 109 Cc

The development of the automotive industry is now experiencing a very rapid increase in the type of motorcycle. One of them is a motorcycle with automatic transmission or automatic motorcycle or CVT (Continously Variable Transmission). Matic motorcycle users often experience a lack of performance when used on daily trips. The mass of CVT rollers and springs is the main factor in the lack of performance of the matic motorcycle which is less efficient for its users. This research was conducted to determine the effect of increasing power and torque on motorcycles that are now declining in performance. The method used in this research is experimentation. Tests were carried out using a dynamometer tool to determine the comparison of the results of the variables carried out and compared to obtain maximum power and torque. The data obtained will be analyzed using statistical methods to evaluate the relationship between changes in roller mass and spring constant to power and torque. The results showed that the maximum power generated was at a roller variation of 11 grams and a spring constant of 33.78 N/cm of 7.19 HP at 6500 rpm engine speed. While the maximum torque is generated from the variation of roller 13 grams and spring 28.83 N / cm of 8.00 Nm at 6000 rpm engine speed.

Improved energy utilization in heavy-duty automatic transmission: Advanced modeling and multi-objective optimization

In the current research of electro-hydraulic actuators for heavy-duty automatic transmissions, achieving accurate output is proven to be insufficient to meet growing demand. Aiming at this deficiency, this paper proposes a dynamic model, which combines detailed loss analysis and multi-objective optimization to further improve energy efficiency. Firstly, considering the key resistance factors, including viscous damping coefficient, spring constant and supply pressure, a dynamic model is established. Subsequently, the overall response of the model is verified based on the existing experimental data. In addition, the accuracy and stability time are used as evaluation indexes to analyze the influence of resistance on the function pattern. Finally, a multi-objective optimization method is used to balance the relationship between energy utilization efficiency, accuracy and shift quality. The slight changes in mechanical energy and stable time lead to a significant decrease in jerk by 22.11 %, which makes the shifting process smoother and effectively improves the shifting performance.

STUDI KASUS PERHITUNGAN TEGANGAN PADA FLAT BELT DALAM APLIKASI MESIN IHR

The Continuously Variable Transmission (CVT) automatic transmission system is a power transmission component widely used in various industrial sectors such as manufacturing, paper, automotive, and electric power. The decision to use this transmission is made due to its ease of maintenance, affordability, and its ability to operate within various power and speed ranges. Key components of the CVT automatic transmission system include flat belts, pulleys, rollers, CVT springs, CVT clutch linings, and clutch clutches. Calculation analysis will be conducted to determine the maximum stress of the flat belt, identify the material of the flat belt, and calculate the lifespan of the flat belt using the IHR machine. The results of the calculation show that the tight side stress is 383.3639 N, the loose side stress is 64.867 N, and the belt material stress is 3.1 N/mm2. These optimal stress and material stress values are deemed suitable for use.