• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.29-37
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• 2007

In the automatic operation of an urban rail vehicle, a conventional PID control algorithm is applied to run the vehicle between stations within time limit and jerk limit. But the energy consumption in the automatic operation is much higher than in the manual operation. In this study, the optimal control algorithm for automatic operation is proposed to minimize energy consumption, which satisfies automatic operation for the urban rail vehicle, compared with the conventional PID control algorithm.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.2
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• pp.227-233
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• 2019

In recent years, vehicle fires account for the second highest rate after residential fires. It accounts for more than 10.7% of the total fire occurrence rate. Vehicle fires are very difficult to evolve at an early stage. Most of the vehicles are burned down in the event of a fire, resulting in a lot of physical and personal damage. In the EU and other countries, efforts are being made to install automatic fire extinguishing systems in preparation for vehicle fires. In addition, since the automatic fire extinguishing system applied to a vehicle must operate in a moving state of a car, a method for detecting a fire is needed. Therefore, this paper proposes a structure of an automatic fire extinguishing system that can evolve a fire when a fire occurs in a commercial vehicle among various vehicles. Especially, it confirms the feasibility of the automatic fire extinguishing system simulated in the laboratory environment and confirms its applicability.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1802-1803
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• 2011

The Korea Railroad Research Institute (KRRI) is developing the Bimodal-tram. The vehicle has a navigation control system (NCS) for automatic driving. The vehicle has to follow a reference path in automatic mode. NCS uses magnetic markers to calculate the vehicle position. The vehicle lane is marked with permanent magnets that are buried in the road. In this purpose, we show the characteristics and the configuration of NCS.

• International Journal of Automotive Technology
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• v.7 no.2
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• pp.155-160
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• 2006

This paper presents a vehicle model for analyzing the transient shifting characterisitics of a passenger car with automatic transmission. Then the presented vehicle model was linked with the dynamic model of an automatic transmission. In order to identify the parameters of the vehicle model, we installed a test equipment with an accelerometer in a conventional vehicle and performed road tests. With the proposed vehicle model, we simulated the dynamic characteristics during shifting, and benchmarked with experimental results. Moreover, a modal analysis was carried out to investigate the effect of the vehicle model in the frequency domain and to obtain the transfer function of the vehicle model. In addition, we showed the numerical results in the time domain for analyzing the effect of each stiffness element, such as engine mountings and suspensions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.149-150
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• 2009

The problem of vehicle routing problem(VRP) with pair operations of pick up and delivery are well-known in real applications in logistics networks, as in planning the routes for automatic guided vehicles(AGVs) in an automatic container terminal(ACT), warehouses or in some just-in-time services. This paper will present a formulation to modeling the problem mathematically which can be used to generate optimal routes of carried vehicles in the field to reduce the incurred cost of moving goods. This selected model could be used in (semi-)automatic short-term planning systems for vehicle fleet working in ACT, or in modern warehouses which the long list of requests is parted and sorted in preprocessing orders systems.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.267-270
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• 2001

A lot of efforts have been made to analyze the performance of the vehicle equipped with automatic transmission through simulation. It might be necessary to understand the different types of transmissions, i.e., different power flows, for different models. If there is a module that can be applied to different types of automatic transmission, it could be helpful to transmission-related engineers. This study has started up from this idea. The common bond graph has been obtained from several types of the automatic transmission. The overall generalized equations and kinematic constraint equations have been derived using virtual power sources on common bond graph. They are used to derive state equations and constraints. These equations have been applied as an application to the vehicle equipped with two simple planetary gear set type of Ravigneaux gear type automatic transmission. The state equation, kinematic constraints, and dynamic constraints have been derived in every gear and shift operation using overall generalized equations and kinematic constraint equations. Simulations for constraint speed running, standing-start running, rolling-start running, and LA-4 mode have been conducted to analyze the performance of the vehicle powertrain using GVPS(Generalized Vehicle Powertrain Simulation) program wit pull down menus.

• Journal of Biosystems Engineering
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• v.21 no.4
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• pp.422-428
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• 1996

This study was conducted to developed to develop a simple battery-powered autonomous vehicle for greenhouse works. A steering method using speed difference of two independent driving motors was adopted. DC motor driving circuit, speed control circuit and controller using one-chip microcomputer were constructed. The inputs of controller are rolling of the vehicle and current speed of driving motors. Using these signals, automatic guidance system along furrow was developed. A computer simulation program by the kenematic analysis was developed to find out optimal control algorithm. The results of this study are as follows. 1. Automatic guidance system along the furrow that adopted two independent driving motors and rolling of vehicle was developed. 2. The results of simulation showed that PID control was adequate to automatic guidance system along furrow. 3. Two commercial 12V battery serially connected were able to drive the vehicle on the soil ground for five hours in continuous operation and for four hours in intermittent operation without recharging the battery. 4. The speed range was 0-0.7m/s and the rolling of vehicle could be controlled within $pm5^{\circ}$ range. 5. From a series of tests, developed vehicle was found to be a useful tool for greenhouse works.

• Journal of the Korean Institute of Intelligent Systems
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• v.4 no.3
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• pp.32-48
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• 1994

This paper proposes the compensation algorithm of conventional shift pattern using fuzzy reasoning in automatic transmission vehicles. Recently, automatic transimssion vehicles are continually increasing because of theire ease to drive. Also users require the high performance which includes the smooth shift quality and shift scheduling that matches driver;s intentions. So the shift scheduling has been inproved significantly through the application of electronic control. But, in spite of this development, vehicles using conventional shift pattern are sometimes in discord with driver's intention on roads. In this paper, the paper, the proposed compensation algorithm makes a automatic transmission vehicle be able to select an optimal gear shifting time and position using fuzzy reasoning and make a vehicle driver feel confortable even when the vehicle runs on roads which is extremely changed. Therefore, a vehicle driver can expect to reduce the nimber of unnecessary gear shifting and expect the fuel efficiency high. To show usefulness of the proposed method, some simulation are made to compared with conventional gear shifting. Paper prosposes the compensation mehtod of conventional shift pattern using fuzzy reasoning for the purpose that a vehicle can select an optimal gerar shifting time and position in automatic vehicle. Though the conventional shift pattern has no pliability, vehicle driver can feel comfortable and can reduce the number of unnecessary gear shifting using the proposed method on variable road condition. Therefore, it can be expected the fuel efficiency.

• Proceedings of the KSR Conference
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• 2005.11a
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• pp.107-112
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• 2005

When it comes to automatic operation control of urban rail vehicle, a PID control makes it run between stations within the fixed time and stop exactly at the stop sign on the platform, satisfying jerk limit. An optimal control is applied to automatic operation performance control to minimize energy consumption while the urban rail vehicle satisfies automatic operation condition on this paper. The control performance in terms of energy minimization along with the constraint on precision stops is compared between the optimal control and PID control.

• Journal of Mechanical Science and Technology
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• v.19 no.spc1
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• pp.395-402
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• 2005

This paper deals with modeling and computer simulation of a full multibody vehicle model for a driving simulator. The multibody vehicle model is based on the recursive formulation and a corresponding simulation code is generated automatically from AUTOCODE, which is a symbolic computation package developed by the authors using MAPLE. The paper describes a procedure for automatically generating a highly efficient simulation code for the full vehicle model, while incorporating realistically modeled components. The following issues have been accounted for in the procedure, including software design for representing a mechanical system in symbolic form as a set of computer data objects, a multibody formulation for systems with various types of connections between bodies, automatic manipulation of symbolic expressions in the multibody formulation, interface design for allowing users to describe unconventional force-and torque-producing components, and a method for accommodating external computer subroutines that may have already been developed. The effectiveness and efficiency of the proposed method have been demonstrated by the simulation code developed and implemented for driving simulation.