• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.133-139
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• 1997

This paper presents a new approach to the dynamic control technique for track vehicle system using neural network-fuzzy control method. The proposed control scheme uses a Gaussian function as a unit function in the neural network-fuzzy, and back propagation algorithm to train the fuzzy-neural network controller in the framework of the specialized learning architecture. It is propored a learning controller consisting of two neural network-fuzzy based on independent resoning and a connection net with fixed weights to simply the neural network-fuzzy. The performance of the proposed controller is shown by simulation for trajectory tracking of the speed and azimuth of a track vehicle

• Journal of KSNVE
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• v.8 no.4
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• pp.683-689
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• 1998

A control algorithm for multi-stage dampers is developed based on the mode skyhook control concept, and implemented on the full vehicle system environment. The test vehicle system is equipped with the real time controller, four-stage variable dampers and sensors. The real time controller is developed using a digital signal processor(DSP), digital I/O, A/D and D/A converters. The dampers are driven by the electromagnetic actuators of less than 20 msec response time. The sensors include accelerometers, relative displacement transducers, and steering wheel rate sensors, etc. Through a series of tests in laboratory and proving ground, the performance of the semi-active suspension system is evaluated and it is shown that the vehicle dynamic characteristics is improved with the developed damping system. Futhermore, the parameter tuning methods to enhance vehicle dynamic performance are propsoed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.4
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• pp.291-298
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• 2011

According to the developments of automobile industry, the technology to enhance noise, vibration and harshness(NVH) performance has been studying in a point of view of ride comfort and quietness. Especially the use of computer aided engineering(CAE) simulation tools such as finite element(FE) analysis allows engineers to efficiently evaluate NVH performance. This paper presents the method to bulid FE models for full vehicle including engine, transmission. suspension and steering system, also to evaluate vibration performance of full vehicle. The full vehicle model, which is discussed, is correlated with the result of the frequency response measurement in the case of the car shake performance for high speed driving.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.1
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• pp.27-35
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• 2008

A navigation system is one of the important components of an unmanned ground vehicle (UGV). A GPS receiver collects data signals transmitted by (Earth orbiting) satellites. However, these data signals may contain many errors resulting misinformation and depending on one's position (environment), reception may be impossible. The proposed self-driven algorithm uses three low-cost GPS in order to minimize errors of existing inexpensive single GPS's driving algorithm. By using reliable final data, which is analyzed and combined from each of three GPS's received data signals, gathering a vehicle's steering performance information and its current pin-point position is improved even with error containing signals or from a place where signal gathering is impossible. The purpose of this thesis is to explain navigation system algorithm using multiple GPS and compass sensor and prove the algorithm through experiments.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.1
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• pp.109-118
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• 2005

A functional suspension model is proposed as a kinematic describing function of the suspension that represents the relative wheel displacement in polynomial form in terms of the vertical displacement of the wheel center and steering rack displacement. The relative velocity and acceleration of the wheel is represented in terms of first and second derivatives of the kinematic describing function. The system equations of motion for the full vehicle dynamic model are systematically derived by using velocity transformation method of multi-body dynamics. The comparison of field test results and simulation results of the ADAMS/Car demonstrates the validity of the proposed functional suspension modeling method. This model is suitable for real-time vehicle dynamics analysis.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.3
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• pp.1-9
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• 2007

A major concern for Autonomous Military Robot in the rough terrain is the problem of moving robot from an initial configuration to goal configuration. In this paper, We generate a local path to looking for the best route to move an goal configuration while avoiding known obstacle from world model, not violating the mobility constraints of robot. Trough a Simulator for Unmanned Autonomous Vehicle, We can simulate a traversability of unmanned autonomous vehicle based on steering, acceleration, braking command obtained from local path planning.

• International Journal of Automotive Technology
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• v.7 no.2
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• pp.201-208
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• 2006

This paper describes the control philosophy of ESP(Electronic Stability Program) which consists of the stability control the fault diagnosis and the fault tolerant control. Besides the functional performance of the stability control, robustness of control and fault diagnosis is focused to avoid the unnecessary activation of the controller. The look-up tables are mentioned to have the accurate target yaw rate of the vehicle and obtained from vehicle tests for the whole operation range of the steering wheel angle and the vehicle speed. The wheel slip control with a design goal of wheel slip invariance is implemented for the yaw compensation and the target wheel slip is determined by difference between the target yaw rate and actual yaw rate. Since the ESP has a high severity level and the robust control is required, the robustness margin for the stability control is determined according to several uncertainties and the robust fault diagnosis is performed. Both computer simulation and test results are shown in this paper.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.10 s.253
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• pp.1276-1283
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• 2006

This study proposes two ESP systems which are designed to enhance the lateral stability of a vehicle. A BESP uses an inner rear wheel braking pressure controller, while a EBESP employs an inner rear wheel and front outer wheel braking pressure controller. The performances of the BESP and EBESP are evaluated for various road conditions and steering inputs. They reduce the slip angle and eliminate variation in the lateral acceleration, which increase the controllability and stability of the vehicle. However EBESP enhances the lateral stability and comfort. A driver model is also developed to control the steer angle input. It shows good performances because the vehicle tracks the desired lane very well.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.2
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• pp.173-182
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• 2001

Ascent trajectory optimization and optimal explicit guidance problems for a satellite launch vehicle in a 2-dimensional pitch plane are studied. The trajectory optimization problem with boundary conditions is formulated as a nonlinear programming problem by parameterizing the pitch attitude control variable, and is solved by using the SQP algorithm. The flight constraints such as gravity-turn are imposed. An optimal explicit guidance algorithm in the exoatmospheric phase is also presented, the guidance algorithm provides steering command and time-to-go value directly using the current states of the vehicle and the desired orbit insertion conditions. To verify the optimality and accuracy of the algorithm simulations are performed.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.895-896
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• 2006

This paper proposes a new method to measure the ECG signal from the driver. The ECG signal is often measured in the room. But it is mixed with many kinds of noise when we measure it during the vehicle moving. We classified noise occupied most many parts as the experimental among them. And we designed one suitable filter for each noise. It used ALE(Adaptive Line Enhancement) to remove the noise occurred to electromagnetic wave in vehicle. To remove the noise occurred to steering or vibration of vehicle, we used Wavelet transformation after ALE(preprocessing filter).