• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1694-1699
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• 2003

A windshield wiper system plays a key part in assuring the driver's safety during the rainfall. However, because the quantity of rain and snow vary irregularly according to time and the velocity of the automobile, a driver changes wiper speed and interval from time to time to secure enough visual field in the traditional windshield wiper system. Because a manual operation of windshield wiper distracts driver's sensitivity and causes inadvertent driving, this is becoming a direct cause of traffic accidents. Therefore, this paper presents the basic architecture of a vision-based smart windshield wiper system and a rain sensing algorithm that regulates speed and interval of the windshield wiper automatically according to the quantity of rain or snow. This paper also introduces a fuzzy wiper control algorithm based on human's expertise, and evaluates the performance of the suggested algorithm in an experimental simulator.

• 자동차안전학회지
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• 제16권2호
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• pp.44-50
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• 2024

The windshield of a vehicle plays an important role in ensuring driver safety and maintaining visibility. To prevent issues such as frost and mist from occurring inside and outside the vehicle, research related to the defrosting performance of the windshield is being conducted. Evaluating defrosting performance requires accurate thermal flow analyses. Therefore, in this study, a defrosting duct was constructed within a chamber at an actual vehicle scale to evaluate its performance, and a finite element model was developed and verified. To evaluate defrosting performance, the temperature of the windshield was measured under condition with a mass flow rate of 0.1 kg/s, which corresponds to that of a typical midsize vehicle. A total of 45 thermocouples were arranged at equal intervals of 9 widths and 5 lengths on the windshield to measure the temperature and compare it with the temperature predicted through finite element analysis. A volume grid was created in the main flow area to ensure accurate thermal flow analyses, and a prism layer was added at the interface between the windshield and fluid. In total, 6 million grid systems were formed. Comparing the temperature fields of the experimental results and the finite element analysis results confirmed a similar defrosting pattern, with an average temperature difference of 0.64K.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2001년도 춘계 학술대회논문집
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• pp.176-180
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• 2001

For windshield defrosting, flow analysis of inner room(vehicle) and heat conduction on the windshield surface are undertaken. Simulation for defrosting enthalpy method is usedand verification of heat and fluid flow analysis for room is done in cavity flow. The defrosting process is three dimensional phenomena and phase is changing. The result of defrosting analysis are well presenting the phase change and these results offer basic design data for defrosting phenomena.

• 한국자동차공학회논문집
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• 제15권5호
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• pp.1-8
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• 2007

The present research is based upon the numerical analysis of a car windshield in order to represent the optimum design guide to improve the overall defrosting performance of the system. First, the control factors that highly affect the defrosting performance of a car windshield are chosen and afterwards, the optimum variables of each control factor are extracted out to analyze its performance. The main control factors for this research are respectively, the air injection angle of a defroster nozzle, the height of a nozzle outlet, and the ratio of the width to the height of a nozzle outlet. For such case when the air inlet angle is relatively small, the flow near the vicinity of the inner face of a windshield tends to expand. As a consequence, the heat transfer rate through the windshield decreases. Also, the height of a nozzle outlet is recommended to maintain its size to minimum. However, when the ratio mentioned before is designed less than unity, the defrosting performance decreases.

• 대한기계학회논문집B
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• 제35권4호
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• pp.345-352
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• 2011

고속으로 주행하는 자동차에서 전면유리 와이퍼의 부상 현상은 와이퍼의 닦임 성능을 저해하여 운전자의 안전을 위협한다. 본 연구에서는 고속 주행 시 와이퍼가 작동하는 차량 주변의 3차원 CFD 해석을 수행하여 와이퍼의 닦임 성능 향상을 위한 방안을 모색하였다. 정확한 해석결과를 얻기 위하여 차량과 와이퍼의 자세한 형상을 모델링하였고, 해석 결과로 와이퍼의 양력계수와 항력계수를 산출하였다. 또한, 수치해석을 통하여 와이퍼 작동 각도와 후드 끝단 각도가 전면유리 와이퍼의 양력계수와 항력계수에 미치는 영향에 대하여 분석하였다.

• Advances in aircraft and spacecraft science
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• 제1권2호
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• pp.233-251
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• 2014

Each aircraft have to be certified for a specified level of impact energy, for assuring the capability of a safe flight and landing after the impact against a bird at cruise speed. The aim of this research work was to define a scientific and methodological approach to the study of the birdstrike phenomenon against several windshield geometries. A series of numerical simulations have been performed using the explicit finite element solver code LS-Dyna, in order to estimate the windshield-surround structure capability to absorb the bird impact energy, safely and efficiently, according to EASA Certification Specifications 25.631 (2011). The research considers the results obtained about a parametric numerical analysis of a simplified, but realistic, square flat windshield model, as reported in the last work (Grimaldi et al. 2013), where this model was subjected to the impact of a 1.8 kg bird model at 155 m/s to estimate the sensitivity of the target geometry, the impact angle, and the plate curvature on the impact response of the windshield structure. Then on the basis of these results in this paper the topic is focused about the development of a numerical simulation on a complete aircraft windshield-surround model with an innovative configuration. Both simulations have used a FE-SPH coupled approach for the fluid-structure interaction. The main achievement of this research has been the collection of analysis and results obtained on both simplified realistic and complete model analysis, addressed to approach with gained confidence the birdstrike problem. Guidelines for setting up a certification test, together with a design proposal for a test article are an important result of such simulations.

• Journal of Mechanical Science and Technology
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• 제20권9호
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• pp.1418-1427
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• 2006

Windshield wipers play a key role in assuring the driver's safety during precipitation. The traditional wiper systems, however, requires driver's constant attention in adjusting the wiper speed and the intermittent wiper interval because the amount of precipitation on the windshield constantly varies according to time and vehicle's speed. Because the manual adjustment of the wiper distracts driver's attention, which may be a direct cause of traffic accidents, many companies have developed automatic wiper systems using some optical sensors with various levels of success. This paper presents the development of vision-based smart windshield wiper system that can automatically adjust its speed and intermittent interval according to the amount of water drops on the windshield. The system employs various image processing algorithms to detect water drops and fuzzy logic to determine the speed and the interval of the wiper.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1727-1730
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• 2003

A windshield wiper system plays a key part in assurance of driver's safety at rainfall. However, because quantity of rain and snow vary irregularly according to time and velocity of automotive, a driver changes speed and operation period of a wiper from time to time in order to secure enough visual field in the traditional windshield wiper system. Because a manual operation of windshield wiper distracts driver's sensitivity and causes inadvertent driving, this is becoming direct cause of traffic accident. Therefore, this paper presents the basic architecture of vision-based smart windshield wiper system and the rain sensing algorithm that regulate speed and operation period of windshield wiper automatically according to quantity of rain or snow. Also, this paper introduces the fuzzy wiper control algorithm based on human's expertise, and evaluates performance of suggested algorithm in simulator model. In especial, the vision sensor can measure wide area relatively than the optical rain sensor. hence, this grasp rainfall state more exactly in case disturbance occurs.

• 전기학회논문지
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• 제65권8호
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• pp.1392-1399
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• 2016

Blackout effect occurs when a driver misadapts to the changed lighting conditions upon entering a tunnel. This could lead to a decrease in visibility especially in the daylight, depending on the difference in the degree of brightness between inside and outside the tunnel. To alleviate such a problem, we decrease windshield transparency before the driver arrives at the tunnel entrance. Controlled amount of light inside the car can allow the drivers to adjust to the dark prior to entering. The windshield transparency coefficient is to be determined by the arrival time at the tunnel and difference in the level of brightness between inside and outside the tunnel. Navigation, road sign detection, and tunnel entrance detection provide the arrival time. We also designed an opto-electronic conversion function to estimate the level of brightness. The black-hole phenomenon alleviation method is verified by field experiments using an automobile camera and a navigation. The result shows that the adjusted windshield transparency is able to provide an environment with a comfortable level of brightness with which the drivers can enter tunnels without the visibility problem.

• 대한기계학회논문집
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• 제10권4호
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• pp.450-455
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• 1986

본 연구에서는 직교좌표계 및 Euler-Lagrange 방법을 이용하여 유도된 기본 방정식을 사용하여 앞창닦기기구(windshield wiper mechanism)의 동력학적 해석을 하 였다.모우터가 일정한 각속도로 회전하고 있는 경우와, 토오크가 각속도의 크기에 따라 변화하는 경우 각각에 대해서 강체로 해석할 때와 탄성체로 가정할 때의 해석결 과를 비교하였다.