• Transactions of the Korean hydrogen and new energy society
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• v.28 no.1
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• pp.56-62
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• 2017

Although most electricity production contributes to air pollution, the vehicle organizations and environmental agency categorizes all EVs as zero-emission vehicles because they produce no direct exhaust or emissions. Currently available EVs have a shorter range per charge than most conventional vehicles have per tank of gas. EVs manufacturers typically target a range of 160 km over on a fully charged battery. The energy efficiency and driving range of EVs varies substantially based on driving conditions and driving habits. Extreme outside temperatures tend to reduce range, because more energy must be used to heat or cool the cabin. High driving speeds reduce range because of the energy required to overcome increased drag. Compared with gradual acceleration, rapid acceleration reduces range. Additional devices significant inclines also reduces range. Based on these driving modes and climate conditions, this paper discusses the performance characteristics of EVs on energy efficiency and driving range. Test vehicles were divided by low / high-speed EVs. The difference of test vehicles are on the vehicle speed and size. Low-speed EVs is a denomination for battery EVs that are legally limited to roads with posted speed limits as high as 72 km/h depending on the particular laws, usually are built to have a top speed of 60 km/h, and have a maximum loaded weight of 1,400 kg. Each vehicle test was performed according to the driving modes and test temperature ($-25^{\circ}C{\sim}35^{\circ}C$). It has a great influence on fuel efficiency amd driving distance according to test temperature conditions.

• Journal of Advanced Navigation Technology
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• v.24 no.4
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• pp.251-260
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• 2020

Unlike manned aerial vehicles, because an unmanned aerial vehicle (UAV) has a limitation which allows only remote test during flights, it is very important to maintain the high reliability of the vehicle through pre- and post-flight tests. To this end, this paper designed an air vehicle test equipment (AVTE) for UAV which meets the derived hardware and software requirements. Based on this design, the AVTE was implemented in accordance with the actual test scenario. The implemented AVTE has the advantage of reducing the time and cost required for the test of UAV by allowing the operator to perform automatic or manual tests for necessary parts in various situations such as before and after starting engine and pre- and post-flight tests. Furthermore, this study is expected to help with the design and implementation of AVTE for other UAVs.

• Journal of Auto-vehicle Safety Association
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• v.10 no.4
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• pp.33-39
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• 2018

Recently, the automobile industry has developed ADAS (Advanced Driver Assistance System) to prevent traffic accidents and reduce driver's driving burden. Among the ADAS, the LKAS (Lane Keeping Assistance System) is a support system for the convenience and safety of the driver, and the main function is to maintain the driving lane of the vehicle. LKAS is a system that uses radar sensor and camera sensor to collect information about the position of the vehicle in the lane and to support keeping the lane through control if necessary. In many countries, LKAS has already been commercialized and the convenience and safety of drivers have been improved. The international LKAS evaluation test procedure is being developed and discussed by standardization committees such as the ISO (International Organization for Standardization) and the Euro NCAP (New Car Assessment Program). In Korean, the LKAS test method is specified in the KNCAP (Korean New Car Assessment Program), but the evaluation method is not defined. Therefore, the LKAS test procedure that meets international standards and is suitable for domestic road environment is necessary. In this paper, development of LKAS test evaluation scenarios that meets international standards and considering domestic road environment, and the formula that can evaluate the result value after control as the relative distance of lane and the front wheel are suggested. And a comparative analysis was conducted to verify the validity of the suggested scenario and formula. The test evaluation was conducted using the vehicle equipped with the LKAS.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1389-1394
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• 2010

This paper describes the evaluation of structural integrity and dynamic characteristic of inertial load test equipments for performance test of railway vehicle propulsion control system. The propulsion control system of railway vehicle has to be confirmed of safety and reliability prior to it's application. Therefore, inertial load test equipments were designed through theoretical equation for performance test of propulsion control system. The structural analysis of inertial load test equipments was conducted using Ansys v11.0 and it's dynamic characteristic was evaluated the designed using Adams. The results showed that the structural integrity of inertial load test equipment was satisfied with a safety factor of 10.2. Also, the structural stability was proved by maximum dynamic displacement of 0.82mm.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.2
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• pp.112-117
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• 2009

The new suspension, called ISU(In-arm suspension system) was developed for Infantry Fighting Vehicle. During vehicle field test, early failure of ISU's sealing system was occurred after driving the paved road. From the failure analysis, ISU's displacement data was obtained. In analysis of PSD data, track induced vibration which has high frequency and small amplitude characteristics, was dominant. Such track vibration would result in early seal failure because of friction increase and lack of lubrication. To simulate track vibration environment in laboratory, seals were tested under the condition of 20Hz, ${\pm}1$, ${\pm}2mm$ amplitude. The same type of seal failure occurred in vehicle test, was reproduced in the lab test under ${\pm}1mm$ amplitude. From the test results, the durability of improved seal was increased by 2.5 times compared with the previous one.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.783-787
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• 2007

Nowadays, vehicle becoming necessity is increasing gradually and is main cause of environmental problem. The current automobile noise measurement test method such as ISO 362 which have been used many countries contribute seriously to enforce the regulation of the noise rigidly and actively study vehicle's noise, using that method. However, the amendment of ISO 362 was completed under the international agreement due to the changes in vehicle's techniques and road conditions. In this study, the difference between the current ISO 362(or ECE R51) and new ISO 362(or new ECE R51) is estimated by the test using the practical car producing domestically because the Korean manufacturer have to be interested in new test method.

• Journal of Auto-vehicle Safety Association
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• v.9 no.1
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• pp.25-31
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• 2017

Small Overlap test decided on IIHS (Insurance Institute for Highway Safety) evaluates a robustness of the car body and a passenger injury protection. A current vehicle is satisfied with a robustness of the car body for Small Overlap test but not meet the requirements of passenger injuries because it is difficult to inquire into the actual state of injury mechanism for Small Overlap test. The study shows the new injury mechanism which represents the relation between a structure of the vehicle placed with the lift foot and the low extremity injury.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.155-160
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• 2001

The road simulator system can simulate the longitudinal, lateral, and vertical movement changed by road conditions and vehicle dynamic characteristics while driving. This system provides the durability evaluation of vehicle suspensions. The system consists of hydraulic actuators, link mechanism, and servo controller. The hydraulic actuators are specially manufactured using low friction seals to endure high speed movement. The link mechanism is designed in order to minimize the dynamic effect during motion and remove the interference between 3axes actuators. The servo controller is composed of sensors, sensor amplifiers - displacement transducers and load cells, and an industrial PC with DSP board which calculates the control algorithm to control hydraulic actuators. The test results are included to evaluate the performance of this simulator comparing vehicle driving test.

• Proceedings of the KSR Conference
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• 2003.10a
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• pp.156-161
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• 2003

Korean High Speed Train (KHST) has been tested on high speed line in JungBu site since it was developed in 2002. The data acquisition system was used to test successfully the on-line test for proving the dynamic performance of KHST. The recognition of system vibration mode for railway vehicle is essential to understand the characteristics of design for dynamic system and diagnose the dynamic problems of vehicle system during test and operation. But, up to now, there are the efforts to know the system vibration mode within limit of theoretical field only, not experimental approach with systematic method. The theoretical results are too reliable to apply to real design problem, because it is theoretically based on the homogeneous linear system although the real system have the nonlinear characteristics and vary the environmental conditions. Therefor, in this paper, it is proposed the efficient method of vibration analysis for rail vehicle system and this method apply to KHST to recognize the vibration mode characteristics of it. The results show that this method is able to make the system vibration modes for KHST clear.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1736-1740
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• 2003

There have been various studies to find out the correlation between subjective and objective evaluation ride comfort in vehicle. To be proper, subjective evaluation considers the signal pattern of vibration generated by vehicle. In this study, driving test is carried out to extract the correlation between subjective evaluation by subjects and vibration signals measured on the seat when a test vehicle is passing over test bumpers, which have two sorts of width change and height change respectively. A unique reference bumper is used to be compared with the relative comfort of test bumpers.