• Journal of Positioning, Navigation, and Timing
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• 제9권4호
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• pp.387-395
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• 2020

Accuracy of an integrated Global Positioning System (GPS) / Inertial Navigation System (INS) relies heavily on the visibility of GPS satellites. Especially, its accuracy is dramatically degraded in urban canyon due to signal obstructions due to large structures. In this paper, we propose a new integrated positioning system that effectively combines INS, GPS, ultrasonic sensor, and barometer in GPS-denied environments. In the proposed system, the ultrasonic sensor provides velocity information along the forward direction of moving vehicle. The barometer output provides height information compensated for the pressure variation due to fast vehicle movements. To evaluate the performance of the proposed system, an experiment was carried out by mounting the proposed system on a test car. By the experiment result, it was confirmed that the proposed system bears good potential to maintain positioning accuracy in harsh urban environments.

• Current Optics and Photonics
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• 제8권4호
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• pp.375-381
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• 2024

In this report, we present the design, fabrication, and experiment of a static solar system for electric vehicle (EV) applications. The static concentration component is composed of compound parabolic concentrators (CPCs) couplings with multi-junction solar cells, where a flat silicon panel is added to the bottom of the CPV structure to maximize power generation. This design allows the system to collect both direct sunlight and diffused sunlight. The CPCs were fabricated with acrylic with a geometric concentration ratio of 4×. We built a prototype with a (3 × 3) cell array of CPCs with a thickness of 25 mm, which is as thin as conventional flat photovoltaic panels, and performed an outdoor experiment that showed that after six hours of operation, the system had an acceptance angle of approximately 43° and an average daily efficiency of 22.85%.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.2024-2027
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• 2005

This study was aimed to prove the safety of rubber-tired AGT light rail vehicle, which was designed to have the redundant equipment for safety, so the experiment of this paper was operated in condition of malfunction which we made such as bake sequence test and momentary interruption test. The result can bes handled by Labview 7.0 and showed as the graph.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.53.3-53
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• 2002

1. Introdition : The necessity of DGPS data compensation. 2. Configuration of the GPS and coordinates conversion 2-1. Coordinates conversion of CCD 3. Vehicle Model and Evaluation 4. Accurate error position algorithm. 5. Experiment and result. 6. Conclusion: It was possible that we converted the CCD data into the GPS coordinates data.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.851-856
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• 2002

In this study, the property against low velocity of the compesite material, which will be applied a rail vehicle, is shown using experiment and a finite element code. The property can be denoted the resistance of impact force, which is defined by maximum impact force over damage area. A damage propagation model is necessary to estimate accurately the impact property of a composite material through FEM code.

• 대한기계학회논문집A
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• 제31권12호
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• pp.1131-1138
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• 2007

This paper studies experimentally on the building-up process for the amplitude of a commercial truck vibration induced by brake judder. A front axle drum equipped with a drum brake system is utilized for this experiment. A brake dynamo test, a real vehicle ride test and a real vehicle braking test are performed for the analysis of brake judder. The brake dynamo test measures judder by applying brake chamber pressures of 1, 2 and 3 bar at initial brake pad temperatures of $100^{\circ}C$ and $150^{\circ}C$. In order to assess the vertical acceleration at the front axle, the real vehicle ride test on a straight test road with velocities of 20, 40, 60 and 80 km/h is performed. The real vehicle braking test is carried out at the deceleration rate of 0.2g from a velocity of 90km/h for evaluating the vertical, lateral and longitudinal accelerations both at the front axle and at the cab floor under the driver's seat. The magnitudes and frequencies of the measured peak accelerations from the brake dynamo test, the real vehicle ride test and the real vehicle braking test are comparatively analyzed. This paper shows that the vibration produced by brake judder is built up due to the brake system's peak acceleration frequency being close to the vehicle ride mode's frequency.

• 전자공학회논문지
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• 제51권9호
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• pp.208-214
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• 2014

차선유지 제어시스템, 적응식순항 제어시스템과 같은 첨단운전 지원시스템은 기본적으로 차량의 거동 정보를 기반으로 구동되지만, 최근 도로의 기하학적 정보를 추가적으로 활용하는 연구가 활발히 진행되고 있다. 특히, 도로의 종단경사는 차량의 가감속 제어 및 항법알고리즘 구현에 있어 필수적인 정보로서 DGPS-RTK와 같은 고가의 장비로 직접 측정하는 방법과 디지털 맵에 저장된 속성정보를 활용하는 방식이 제안되고 있으나, 상용화 관점에서는 아직 많은 문제점이 존재한다. 따라서, 본 논문에서는 추가 센서의 장착없이 연속형 확장칼만필터를 활용하여 차량의 동특성과 도로종단경사를 효율적으로 추정하는 알고리즘을 제안한다. 도로종단경사를 포함하는 3자유도 차량동역학 모델과 차량의 내부 네트워크롤 통해 수집할 수 있는 차량의 상태정보를 기반으로 확장칼만필터를 설계하여 차량의 동특성과 도로종단경사를 추정한다. 제안된 알고리즘은 시뮬레이션과 실차실험을 통해 그 성능을 검증하였다.

• 동력기계공학회지
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• 제21권3호
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• pp.51-59
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• 2017

In the early design stage of underwater vehicles, it is important to estimate the vehicle's underwater motion performance. The key design elements for the motion are propellers, battery power, and underwater resistance of the vehicle. Small thrusters with motor and propeller are usually used for the UUV(unmanned underwater vehicles). In this study, a multiphysics thruster model combining electro-mechanical and hydrodynamics characteristics was proposed to estimate the thruster performance. To show the applicability of the mathematical model, an sample thruster was used for the derive the unknown parameters of thruster. Hydrodynamic parameters were calculated for a 3D geometry model of the propeller by ANSYS/CFX program. Finally, Matlab/simulink program was used for the numerical simulation to predict the thruster performance from the given voltage/current input to the motor. Also, proved validity of simulation model by experiment test. Test were done by 2 mode(middle/high speed, reverse). The thruster performance curves obtained from this simulation were confirmed to be similar with experiment results.

• 동력기계공학회지
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• 제18권5호
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• pp.11-15
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• 2014

Currently, there are active researches being conducted on a new combustion technology that can reduce emission quantity while enhancing vehicle performance as well as Improving fuel quality. In a gasoline engine that uses petroleum, high volatility makes it easy to jump spark ignition and prevent knocking phenomenon that occurs inside an engine. In a diesel engine that uses diesel fuel, high volatility reduces combustion residues and toxic gas and is therefore good for protecting the environment. Therefore, for fuel used in a vehicle, volatility is an important factor that influences not only engine performance but also environmental protection. This research conducted a distillation experiment using gasoline and diesel fuel for vehicles produced by domestic oil companies. The test was conducted in accordance with the method of distillation experiment described in KS M ISO3405. In addition, it used the result of analysis from the experiment to examine visual distillation characteristics of each fuel and developed a formula based on distillation temperature.

• 제어로봇시스템학회논문지
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• 제15권2호
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• pp.155-162
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• 2009

In walking guide robot, a guide vehicle detects an obstacle distribution in the walking space using range sensors, and generates a 3D grid map to map the obstacle information and the tactile display. And the obstacle information is transferred to a blind pedestrian using tactile feedback. Based on the obstacle information a user plans a walking route and controls the guide vehicle. The algorithm for 3D detection of an obstacle distribution and the method of mapping the generated obstacle map and the tactile display device are proposed in this paper. The experiment for the 3D detection of an obstacle distribution using ultrasonic sensors is performed and estimated. The experimental system consisted of ultrasonic sensors and control system. In the experiment, the detection of fixed obstacles on the ground, the moving obstacle, and the detection of down-step are performed. The performance for the 3D detection of an obstacle distribution and space mapping is verified through the experiment.