• Transactions of the Korean Society of Automotive Engineers
• /
• v.24 no.3
• /
• pp.372-378
• /
• 2016

Clutch torque control is the key to the ride comfort improvement of a vehicle equipped with AMT (automated manual transmission). For such control, the torque transfer starting point, known as the "kiss point," should be indicated or at least estimated to compensate for the clutch torque. The kiss point changes due to wear, high temperature, and fatigue; as such, it should be estimated while the vehicle is being driven. In this study, the method of kiss point active estimation for an AMT vehicle with a dry-type clutch was devised. The kiss point is learned while the engine is in an idle state and while the transmission is at a neutral gear position. It is determined when the input shaft of the transmission starts to rotate by slowly engaging the clutch. The noise of the shaft speed signal during the slow engagement process is filtered for accurate control. The kiss point estimation at various clutch engagement speeds was analyzed via a vehicle test.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.11
• /
• pp.88-93
• /
• 2000

Recently the gear design focuses on the optimal design to extract the design factors from the vehicle transmission that is required to equip the powerful, speedy and silent characteristics. In this study, we had determined modules($m_n$) and face widths (b) to sustain strengths of contact and bending. The pressure angle ($\alpha$) and the helix angle ($\beta$) also had been obtained from the constraint of a contact ratio ($\varepsilon) on helical gears. Through the optimal design algorithm suggested in this study, the design factors were calculated on vehicle transmission gears and those determined factors were able to firm a suitability of the design.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.6 no.3
• /
• pp.149-156
• /
• 2011

Transmission delay and packet loss induced by a communication network can degrade the control performance and, even make the system unstable. This paper presents a method for compensating transmission delay and packet loss in a networked control system for unmanned underwater vehicle. The proposed method is based on Lagrange interpolation in order to satisfy the requirements of simplicity and model-independency. In this work, the lost/delayed data are estimated in real time by only using the past data without requiring any mathematical model of the controlled system. Consequently, the proposed method can be implemented independent of the controlled system, and also it can achieve fast and accurate compensation performance. The performance of the proposed technique is evaluated by numerical simulations with an unmanned underwater vehicle.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.24 no.3
• /
• pp.287-293
• /
• 2015

With the rise in oil prices and ongoing concerns about environment, there is an increased amount of interest in automated manual transmission (AMT) vehicles. Torque control in an AMT vehicle is attained by controlling the displacement of the dry-type clutch's actuator. To provide good ride comfort akin to that of an automatic transmission vehicle, the clutch control is vital to an AMT vehicle. In this study, a method of obtaining the clutch torque from a dynamometer test is devised. This method is able to identify the relationship between the displacement of the clutch actuator and the clutch torque. A simulator for estimating the performance of an AMT vehicle is developed using MATLAB Simulink. The results obtained from both the vehicle and simulation exhibit a similar trend.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.14 no.5
• /
• pp.107-114
• /
• 2006

This paper investigates the radiating source of electro-magnetic waves in the cabin of automobile with spark ignition engine. Front seats are very close to the engine room where electro-magnetic waves are expected to be radiating. But front seat area is believed to be a blind zone, which is not affected by radiating electro-magnetic waves, because a bulk board and floor board shield the front seat area. The level and frequency spectrum of electro-magnetic waves are measured at the passenger seat and the engine room. The measured frequency range is $145{\sim}365MHz$. As a results, the level of the electro-magnetic waves of automatic transmission vehicle is greater than -82dBm. The shapes of frequency spectrum of both engine room and passenger seat are look alike. But the level of electro-magnetic waves of manual transmission vehicle is less than -82dBm and the shapes of frequency spectrum of engine room and passenger seat are different to each other. From these results, we can say that any mal-function caused by electro-magnetic waves in the automobile cabin are only possible for automatic transmission vehicle. Also, it is believed that the radiating source of electro-magnetic waves is inside the vehicle. Thus, based on the transmission line theory, this paper presumably concludes that the cables which connect all the components inside a automatic transmission vehicle must be a radiating source of electro-magnetic waves in the cabin.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.5 no.4
• /
• pp.171-178
• /
• 1997

Vehicle interior noise has become increasingly important in this recent years. The noise of a vehicle is one of the important problems in a vehicle design. The interior noise is caused by various vibration sources of vehicle compartment. The booming noise of a vehicle can be significantly affected by vibrations transmitted from engine excitation forces to the vehicle body. Specially, we are interested in the state of transmission paths such as engine mounts to reduce noise in a vehicle compartment. In this paper, we have been calculated the contribution of each transmission path such as engine mounts to interior noise. To identify contribution of each input sources and transmission paths to output, the effectiveness of each input component to output is calculated. Sensitivity analysis is carried out for investigation of contribution to output due to input variations. With the simulation of magnitude and phase change of inputs using vector synthesis diagram, the trends of synthesized output vector are obtained. As a result, we suggested sensitivity analysis of vector synthesis as a technique of prediction and control for noise in a vehicle compartment.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.6 no.2
• /
• pp.70-80
• /
• 2007

Inter-vehicular communication suffers from a variety of the problem on the road, resulting in large delay in propagating emergency warning. An energy depletion as well as a transmission delay may induced by traffic accident. A transmission delay are caused by direct contention from nodes that can hear each other or indirect contention from nodes that can not hear each other, but simultaneously transmit to the same destination. A variety of works have been researched to solve the transmission delay and energy consumption problem in intelligent cars transportation systems. We consider a vehicle-to-vehicle communication protocol for disseminating an emergency information that include end-to-end and energy efficient transmission. In this paper, we propose A vehicle-to-vehicle communication protocol scheme for dissemination emergency information in intelligent cars communication based on IEEE 802.15.3 wireless personal area networks. Results from a simulation study reveal that our scheme can achieves low latency in delivering emergency warnings, and efficiency in consuming energy in stressful road scenarios.

• Proceedings of the IEEK Conference
• /
• 2001.06e
• /
• pp.51-54
• /
• 2001

For performing Intelligent Transport System, I will implement the vehicle recognition system used image as well as Real time transmission module with TCP/IP. Generally, there are two kinds for vehicle recognition technology. Between two methods, the image-based method has a high dependency on environmental condition. Therefore, in this thesis I will propose vehicle recognition algorithm based on image using improved Gradient Method. Also I propose server-client modeling with TCP/IP, for the purpose of real time transmission of processed data and images. So I made the vehicle recognition and real time transmission system with TCP/IP for verification of proposed algorithm.

• Tribology and Lubricants
• /
• v.36 no.2
• /
• pp.96-104
• /
• 2020

The electric vehicle industry is rapidly developing because of enforced environmental regulations, and several studies have been conducted on the multispeed transmission to improve the fuel efficiency of electric vehicles. Among these studies, research on the power density improvement of electric vehicle transmission is critical. Thus, the optimal design of the gear train is necessary to enhance transmission efficiency. In this study, an optimal design methodology for the lightweight two-speed transmission of electric vehicles is proposed. Because a multispeed transmission has many operating conditions and equality and inequality constraints, a new gear design method that combines analytical and iterative methods is applied without using complex optimization algorithms. Sets of possible design variables are generated considering the operating conditions and various design variables. The modules and face width ratios of each stage gear that satisfy the corresponding operating conditions are analytically calculated. The volume of the gear train is calculated, evaluated, and arranged using these values to determine the optimal solution for minimizing the volume, and the proposed methodology is applied to the actual model to verify its effectiveness. The design of a two-speed transmission with multiple operating conditions and constraints without complicated optimization algorithms can be optimized.

• Journal of KSNVE
• /
• v.1 no.1
• /
• pp.39-43
• /
• 1991

In this study, the design concept of engine for 4WD vehicle is established by the experimental modal analysis. First, the relationships between frame and power transmission system are considered. Second, the effect of additional system (Front propeller shaft and Exhaust system) on the power transmission system is evaluated. As a result, it is desirable that of frame and power transmission system is shifted by the additional system. This is cause by the moment of inertia of the additional system, because the center of gravity location of the additional system is far from that of the power transmission system.