• Proceedings of the KSME Conference
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• 2000.04a
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• pp.487-492
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• 2000

Yaw moment control algorithm for improving stability of a vehicle in cornering is presented in this paper. A change of the yaw moment according to an increment in brake ship at each wheel is examined and reflected in the control algorithm. This control algorithm computes the target yaw velocity as the vehicle motion desired by the driver for directional stability control in cornering and it makes the actual yaw velocity follow the target one. The yaw moment control was achieved by brake slip control and simple brake slip control logic was introduced in this paper.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.131-132
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• 1998

The purpose of this study is to keep drivers from falling asleep at the wheel, it is necessary to find ways of detecting and relieving drowsiness. For the estimation of our warning system, we measured the physiological parameters such as EEG, ECG, EOG while they performed a monotonous task intended to induce drowsiness. The effects of a oxygen, odor and various colors on the subjects while in a drowsy state were examined. It was found that a combination of a certain amount of oxygen and odor such as a menthol and yellow color can have a positive effect of relieving drowsiness.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.165-172
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• 2000

The VDC(Vehicle Dynamic Control) is a control system whose target is to improve stability of a vehicle under lateral motion. A lateral vehicle motion, especially on a slippery road, can lead to a hazardous situation, and the situation can even worsen by the driver`s inappropriate response. In this paper, two VDC systems, a fuzzy-based controller and an LQR-based controller have been developed. The controllers take as input the yaw rate and the sideslip angle of either body or rear wheel, and they yield the direct yaw moment signal by which the vehicle can gain stability during cornering. Simulations have been conducted to evaluate the performance of the control system. The results indicated that the controllers can successfully improve vehicle stability under potentially dangerous driving conditions.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.03a
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• pp.124-131
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• 1996

The use of small hemispherical high-speed precision bearing has increased drastically these days in the field of computer disk driver, highteech devices as well as communication and electronic device drivers. It was suggested that the new polishing process adopting the diamond grinding wheel and polishing tool instead of multi stage lapping processes, which enables the mass production of the bearing by reduction of polishing time. Polishing mechanism was analysed and the results were applied to the design and manufacturing of the polishing system. Experiments for selection of optimal polishing conditions were carried out using the polishing system.

• International Journal of Control, Automation, and Systems
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• v.5 no.3
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• pp.343-348
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• 2007

This paper presents an adaptive controller for the compensation of state-dependent disturbance with unknown amplitude in a digital servo motor system. The state-dependent disturbance is caused by friction and eccentricity between the wheel axis and the motor driver of a mobile robot servo system. The proposed control scheme guarantees an asymptotical stability for both the velocity and position regulation. An experimental result shows the effectiveness of the adaptive disturbance compensator for wheeled-mobile robot in a low velocity diffusion tracking. A comparative experimental study with a simple PI controller is presented.

• Journal of Applied Reliability
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• v.17 no.3
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• pp.197-206
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• 2017

Purpose: Clarify the cause of the noise by the front wheel strut insulator, which is located in close proximity to the driver's seat. Methods: The improvement mechanism was confirmed through failure analysis and reproduction test of the joint generation mechanism. In addition, the main factors were analyzed through principal test. Results: This paper describes the mechanism of occurrence of noise due to deterioration and hardness increase of rubber, deformation on severe road surface, foreign matter and water inflow in cold weather. Conclusion: We found that the insulator and body deformation can be minimized without increasing the thickness of the body and the insulator and reinforcing the body by dispersing the input load by applying load distribution structure instead of the local forming structure of the insulator in the insulator robust structure.

• International Journal of Railway
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• v.3 no.3
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• pp.90-94
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• 2010

In this paper, driving functions of the Korea High-speed Trains were decomposed based on systems engineering architecture. In order to analyze the driving function, various systems engineering tools and methods were used. Moreover, interfaces of decomposed driving functions were analyzed to figure out purposes of the driving functions. Through activity modeling of driving function of the Korea High-Speed Trains, main functions were derived when starting, speeding and stopping. When the high speed train is speeding, pre-departure checks and wheel slide prevention are essential driving activities for the safety and when the high speed train runs high speed, maintaining driving stability by monitoring bogie hunting and monitoring drivers' safe operation by vigilance systems is important. Furthermore, when the train is braking, the driver should checks brake and suspensions as safety actions.

• Journal of Mechanical Science and Technology
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• v.19 no.spc1
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• pp.444-451
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• 2005

The analysis of human arm motion during steering maneuver is carried out for investigation of man-machine interface of driver and steering system Each arm is modeled as interconnection of upper arm, lower arm, and hand by rotational joints that can properly represents permissible joint motion, and both arms are connected to a steering wheel through spring and damper at the contact points. The joint motion law during steering motion is determined through the measurement of each arm movement, and subsequent inverse kinematic analysis. Combining the joint motion law and inverse dynamic analysis, joint stiffness of arm is estimated. Arm dynamic analysis model for steering maneuver is setup, and is validated through the comparison with experimentally measured data, which shows relatively good agreement. To demonstrate the usefulness of the arm model, it is applied to study the effect of steering column angle on the steering motion.

• International Journal of Automotive Technology
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• v.6 no.5
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• pp.461-466
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• 2005

With the growing traffic density and increasing comfort requirements, the automation of the drive train has gained importance in vehicles. The automatic clutch actuation relieves a driver especially in urban and stop-and-go traffic environments. In this paper, an electro-mechanical actuator for clutch-by-wire (CBW) system is implemented as the first stage for the development of automated manual transmissions. The prototype of the automatic clutch actuator is designed systematically, which is composed of the electric motor, worm and worm wheel, and crank mechanism. A test rig is developed to perform the basic function test for the automatic clutch actuation. The developed prototype is validated by the experimental results performed on the test rig.

• Science of Emotion and Sensibility
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• v.21 no.2
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• pp.29-42
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• 2018

As information technology is more actively incorporated into automobiles, the role of IVIS (In-Vehicle Infotainment System) is becoming increasingly important for providing convenience and entertainment for drivers. However, using the infotainment systems while driving requires task switching and attending to two visual resources simultaneously. We simulated a setting where participants have to drive while interacting with the infotainment system and examined how task difficulty and motor cues impact driver task-switching and driving performance, specifically whether the effects of motor cues differ depending on task difficulty. For the infotainment display, we used two types of number array depending on the congruency between the digit repetition and the chunking unit, while task difficulty was manipulated by the size of the touch-keys. Participants were instructed to dial two numbers on the screen while we recorded the dialing time, lateral position, inter-key press intervals, and steering wheel control. We found that dialing time and lateral position were affected by task difficulty, while the type of number array had no effect. However, the inter-key press intervals between chunked numbers and steering wheel movement both increased when participants had to use an incongruent number array, which indicates that, if number digits are repeated, chunking is ignored by the drivers. Our findings indicate that, in a dual-task condition, motor cues offset the effect of chunking and can effectively signal the timing for task switching.