• 드라이브 ㆍ 컨트롤
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• 제16권1호
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• pp.22-28
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• 2019

This paper develops ABS braking real - time simulator to develop vehicle braking system by simulation. Recently, real-time simulation is widely used in the development of vehicles to decrease development time. In the field of electronic braking, real-time simulation is actively underway. In order to simulate electronic braking model in real time, a vehicle model, a hydraulic model, and a control S/W model are required. These models must be calculated in one platform. Therefore, in this paper, a vehicle model composed of CarSim and a hydraulic model composed of SimulationX using S/W in actual ABS controller was developed as a Simulink model base and linked with Matlab real time model. Using this real-time model, design effects of the electronic braking controller were simulated according to road surface condition to verify its operability.

• 자동차안전학회지
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• 제13권3호
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• pp.6-12
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• 2021

This paper presents a lateral stability control for rear wheel drive (RWD) vehicles using electronic limited slip differentials (eLSD). The proposed eLSD controller is designed to increase the understeer characteristic by transferring torque from the outside to inside wheel. The proposed algorithm is devised to improve the lateral responses at the steady state and transient cornering. In the steady state response, the proposed algorithm can extend the region of linear cornering response and can increase the maximum limit of available lateral acceleration. In the transient response, the proposed controller can reduce the yaw rate overshoot by increasing the understeer characteristic. The proposed algorithm has been investigated via computer simulations. In the simulation results, the performance of the proposed controller is compared with uncontrolled cases. The simulation results show that the proposed algorithm can improve the vehicle lateral stability and handling performance.

• 한국전기전자재료학회논문지
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• 제24권7호
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• pp.554-558
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• 2011

Piezoelectric energy harvester (PEH) as a box type was fabricated in order to harvest mechanical energy imparted to roadways from passing vehicles and convert it into electricity. The PEH was composed of 72 piezoelectric cantilevers with 9 springs with elasticity stick to a bottom of the PEH. For the single piezoelectric cantilever, when a single push with approximately 5 mm displacement was incident to it, power of 0.355 mW was produced at $100\;k{\Omega}$. It is found that the power from the single piezoelectric cantilever increases when spring constant is high. We investigated power of PEH when the moving vehicle passes in it. Power was increased with increasing vehicle speed. When vehicle speed is 30 km/h, power is 20.6 mW.

• 한국컴퓨터정보학회논문지
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• 제17권1호
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• pp.71-80
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• 2012

본 논문에서는 단일 카메라를 이용하여 차량의 위치를 검출하고 연속적인 프레임에서의 차량의 움직임을 추적하는 알고리즘을 제안한다. 차량의 특징을 검출하기 위해 Haar-like 에지 검출기를 사용하고, 카메라의 캘리브레이션 정보를 이용하여 차량의 위치를 추정한다. 신뢰도를 높이기 위해 k 개의 연속적인 프레임에서의 누적된 차량 정보를 추출한다. 최종 검출된 차량을 템플릿으로 지정하고 SURF (Speeded Up Robust Features) 알고리즘을 통해 연속적으로 입력되는 프레임에서 동일한 차량을 추출한다. 이를 통해 동일 차량으로 추출된 차량 정보를 새로운 템플릿으로 업데이트 한다. 비교 검출을 위한 수행 시간을 줄이기 위해 이전 프레임에서 검출된 차량의 범위를 확장한 영역만을 관심 영역으로 지정한다. 이 과정은 공통된 대응점을 찾지 못할 때까지 검출과 추적 과정을 반복하여 진행한다. 실 도로 상에서 얻어진 영상에 대해 적용함으로써 제안된 알고리즘의 효율성을 보였다.

• International Journal of Automotive Technology
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• 제8권2호
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• pp.203-209
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• 2007

As the vehicle electronic control technology quickly grows and becomes more sophisticated, a more efficient means than the traditional in-vehicle driving test is required for the design, testing, and tuning of electronic control units (ECU). For this purpose, the hardware-in-the-loop simulation (HILS) scheme is very promising, since significant portions of actual driving test procedures can be replaced by HIL simulation. The HILS incorporates hardware components in the numerical simulation environment, and this yields results with better credibility than pure numerical simulations can offer. In this study, a HILS system has been developed for ESP (Electronic Stability Program) ECUs. The system consists of the hardware component, which that includes the hydraulic brake mechanism and an ESP ECU, the software component, which virtually implements vehicle dynamics with visualization, and the interface component, which links these two parts together. The validity of HIL simulation is largely contingent upon the accuracy of the vehicle model. To account for this, the HILS system in this research used the commercial software CarSim to generate a detailed full vehicle model, and its parameters were set by using design data, SPMD (Suspension Parameter Measurement Device) data, and data from actual vehicle tests. Using the developed HILS system, performance of a commercial ESP ECU was evaluated for a virtual vehicle under various driving conditions. This HILS system, with its reliability, will be used in various applications that include durability testing, benchmarking and comparison of commercial ECUs, and detection of fault and malfunction of ESP ECUs.

• Journal of Electrical Engineering and Technology
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• 제3권1호
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• pp.135-142
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• 2008

This paper deals with the design of a robust PI controller for a vehicle suspension system. A method, which is related to computation of all stabilizing PI controllers, is applied to the vehicle suspension system in order to obtain optimum control between passenger comfort and driving performance. The PI controller parameters are calculated by plotting the stability boundary locus in the $(k_p,\;k_i)$-plane and illustrative results are presented. In reality, like all physical systems, the vehicle suspension system parameters contain uncertainty. Thus, the proposed method is also used to compute all the parameters of a PI controller that stabilize a vehicle suspension system with uncertain parameters.

• Journal of Positioning, Navigation, and Timing
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• 제9권1호
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• pp.23-31
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• 2020

It is essential to estimate the vehicle localization for an autonomous safety driving. In particular, since LIDAR provides precise scan data, many studies carried out to estimate the vehicle localization using LIDAR and pre-generated map. The road marking always exists on the road because of provides driving information. Therefore, it is often used for map information. In this paper, we propose to generate the Gaussian mixture map based on road-marking information and localization method using this map. Generally, the probability distributions map stores the single Gaussian distribution for each grid. However, single resolution probability distributions map cannot express complex shapes when grid resolution is large. In addition, when grid resolution is small, map size is bigger and process time is longer. Therefore, it is difficult to apply the road marking. On the other hand, Gaussian mixture distribution can effectively express the road marking by several probability distributions. In this paper, we generate Gaussian mixture map and perform vehicle localization using Gaussian mixture map. Localization performance is analyzed through the experimental result.

• 자동차안전학회지
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• 제7권2호
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• pp.32-38
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• 2015

A sine with dwell test is well known as a test scenario for evaluation of performance of electronic stability control(ESC) on passenger vehicles and heavy commercial vehicles. However, when it comes to ESC for medium commercial vehicles, the test scenario has not been established yet. In this paper, the sine with dwell test was modified considering characteristics of medium commercial vehicles. The three main modifications of the original test scenario are the steering angle level, steering frequency, and loading condition of the vehicle. These modifications are derived from simulation study for different medium commercial vehicles. From simulation study, it was shown that the ESC system for medium commercial vehicle is objectively evaluated by the proposed test scenario. A clear improvement on vehicle stability was seen in the results when ESC system was used.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.277-280
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• 2014

Recently, military vehicles that are being driven are equipped with a lot of electronic devices. The military vehicles are easily exposed to impact. Thus, they have to be designed robustly to ensure that the stability of the vehicle and the electronic equipment. In order to design the vehicles efficiently, the dynamic characteristics of a military vehicle have to be identified exactly. The main frame has a significant role to the dynamic characteristics of the vehicle. Thus, this research was progressed mainly with the frame. By carrying out road tests, the characteristics could be identified. Also, based on the characteristics, we constructed FE model of the frame and performed the analysis of the dynamic characteristics of the vehicle.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 추계학술대회 논문집
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• pp.364-369
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• 2012

The vehicle sound classified into driving sound due to power-train, operating sound due to electric motor like sunroof, door lock and electronic sound. These vehicle sound has various features depend on the characteristic of sound that user required. And it based on cultural and regional difference of user. In this study, the user required vehicle sound characteristics for luxury sedan was investigated in overall viewpoint. And virtual target sound was developed through the result of user preference investigation. Next, Jury test was carried out in Germany, USA and Korea for evaluating the target sound. And the regional and individual difference of preference was analyzed through the result of jury test. This result of research will be contributed to design of vehicle sound quality and target sound setting.