• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.1
• /
• pp.72-84
• /
• 2000

To analyze the correlation between drivetrain systems and to optimize the vehicle design with satisfying of the initial design objects, the performance sensitivity analysis through the iterative design procedure must be carried out. In this study, effects of the design parameters for the main components of the parallel type hybrid drivetrain system are analyzed by using the developed method of the vehicle performance simulation, and the basis of the optimal selection of the design parameters from the relation of design constraints and required performances is suggested. In driving control of the parallel hybrid vehicle, power split ratio is the most important factor, and the improved drivetrain system can be constructed through the only change of the algorithm for determination of the power spilt ratio, which is strongly applicable to the driving patterns and the environments. Therefore, Various techniques, such as the change of the weighting factors and the range extended algorithm, are suggested and evaluated in this paper.

• Proceedings of the KSME Conference
• /
• 2001.06b
• /
• pp.552-557
• /
• 2001

To minimize the fuel consumption in the hybrid vehicle, the single performance index, which can express the fuel consumption in engine and electric energe consumption in battery system at the same time, is required. In this study we proposed a single performance index with equivalent BSFC concept, and with this, we constructed driving control algorithm, which can determine optimal gear ratio and power split ratio of the engine and the motor, for the parallel hybrid vehicle. Additionally, to verify the validity of this algorithm, driving simulation is performed.

• Journal of Auto-vehicle Safety Association
• /
• v.12 no.4
• /
• pp.23-30
• /
• 2020

Recently, self-driving research has been actively studied in various institutions. Accurate recognition is important because information about surrounding objects is needed for safe autonomous driving. This study mainly deals with the signal processing of LiDAR among sensors for object recognition. LiDAR is a sensor that is widely used for high recognition accuracy. First, we clustered and tracked objects by predicting relative position and speed of objects. The characteristic points of all objects were extracted using point cloud data of each objects through proposed algorithm. The Classification between vehicle and pedestrians is estimated using number of characteristic points and distances among characteristic points. The algorithm for classifying cars and pedestrians was implemented and verified using test vehicle equipped with LiDAR sensors. The accuracy of proposed object classification algorithm was about 97%. The classification accuracy was improved by about 13.5% compared with deep learning based algorithm.

• Journal of Auto-vehicle Safety Association
• /
• v.14 no.1
• /
• pp.14-19
• /
• 2022

Recently, automobile industries have developed ADAS, smart cars, connected cars, automated driving systems, which communicate with outsides of a vehicle not only in uni-directional way but also in bi-directional way. It is necessary to examine the electromagnetic immunity of vehicles equipped with those communication systems. The electromagnetic immunity tests are carried out in an electromagnetic semi anechoic chamber, which is cut off from the outside electromagnetically. In this study, additional test environments were designed and tested and as a result they are shown to be effective to create test environments in an experimental chamber for electromagnetic immunity tests of vehicles equipped with communication systems.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.2
• /
• pp.152-166
• /
• 2022

This study analyzed the causal relationship among operating characteristics of commercial freight vehicles, dangerous driving behaviors, and traffic accident risk. The study applied the existing accident cause and prevention theory to arrive at this relationship. Data related to working characteristics of driver, driving experience, driving ability, driving psychology, vehicle characteristics (size), dangerous driving behavior, and traffic accidents were collected from 303 commercial freight vehicle drivers. Working characteristics and dangerous driving behavior data are based on the driver's digital driving record. The traffic accident data is based on the insurance accident data reflecting actual traffic accidents. First, a structural equation model was built and verified using the model fitness index. Then, the developed model was used to analyze the causal relationship between multiple independent and dependent variables simultaneously. Four dangerous driving behaviors (sudden deceleration, sudden acceleration, sudden passing, and sudden stop) were found to be highly related to traffic accidents. The results further indicate that it is necessary to establish a safety management policy and intensive management for small-sized freight vehicles, drivers with insufficient driving ability, and drivers with dangerous driving behaviors. Such policy and management are expected to reduce traffic accidents effectively.

• Journal of Biosystems Engineering
• /
• v.38 no.4
• /
• pp.240-247
• /
• 2013

Purpose: This study was conducted to develop a rubber-crawler type vehicle as a traveling device for harvesting water-dropwort cultivated in water contained paddy rice field in winter season. Methods: A commercial rubber-crawler type vehicle was used to investigate application of rubber crawler to the paddy rice field as preliminary test. As the result of the preliminary test, a both prototype traveling device with rubber crawlers for a water-dropwort harvest was designed with inclination of $45^{\circ}$ at the front-end and rear-end of crawler under the basic water depth of 0.6 m in the paddy rice field. The device was fabricated and attached to the experimental harvesting test devices on the front of the prototype vehicle. The size of the prototype crawler vehicle with a harvesting part is $2,800{\times}1,460{\times}1,040 $ (mm) ($L{\times}W{\times}H$) with weight of 9.21 kN (maximum). Sizes of the crawler of prototype vehicle are ground contact length of 900 mm, width of 180 mm, height of 1,070 mm and distance between center to center of crawlers of 720 mm. The side-overturn angle of the prototype was $26.4^{\circ}$. Results: Driving performance of the prototype vehicle in water contained paddy field were good at both forward and reverse (backward) directions as weights were applied. The drawbar pull and the maximum sinking depth of the prototype vehicle were 3.5 kN and 0.13 m respectively at water depth of 0.5 m, when the weight and bearing capacity of the prototype rubber crawler in the paddy field were 8.51 kN and 26.3 $kN/m^2$, respectively. Conclusions: Results of the driving test performance of the prototype crawler in paddy rice field at the water depth of 0.5 m were satisfactory. The prototype had enough drawbar pull and driving ability in the deep water contained paddy field.

• Journal of Korean Institute of Industrial Engineers
• /
• v.38 no.1
• /
• pp.41-45
• /
• 2012

Until now, most studies of foot moving or driving posture have been performed under laboratory driving conditions. But there are many different things between actual driving conditions and laboratory driving conditions because, in laboratory conditions, it is hard to consider vehicle's noise, vibration and people's psychology state while driving. Thus this study is performed through actual driving conditions. And while driving test, we recorded driver's foots with 2 cameras to investigate foots(left and right) heel point and how human foots move to control the three pedals : accel, brake and footrest.. Through driving test, the results of this study show that the position of driver's heel point isn't related to stature and tends to be generalized.

• Journal of Korean Society of Transportation
• /
• v.26 no.6
• /
• pp.39-47
• /
• 2008

With dramatic development of IT technology and start of DMB service, installing the DMB equipment in a vehicle for watching TV programs and literal or pictorial traffic information are increasing. Watching the DMB during driving the vehicle could cause visual and cognitive distraction to drivers as much as eating food, operating radio and using mobile phone. However, there is not much empirical research for this topic and no research examined the effect of watching the DMB on driving behaviors in Korea. So, the present study examined the effect of watching the DMB on the driving behaviors with car simulator experiment. Within subject design was used in the study. That is, all subjects drove the vehicle both in the watching DMB condition and the non-watching DMB condition. The results indicated that subjects in the watching DMB condition took longer time to arrive at the destination and operated accelerator and brake pedal rapidly than subjects in the non-watching DMB condition. That is, their overall driving stability was lower than non-watching subjects'. Additionally, we examined the difference among the DMB control conditions (i.e., keypad condition, touch-pad condition and remote controller condition) in the driving behaviors. Finally, we discussed the limitations and the implications of the present study.

• International Journal of Automotive Technology
• /
• v.1 no.2
• /
• pp.61-69
• /
• 2000

This paper will address the basic requirements for realizing a stop and go cruise control system. Issues discussed comprise: functional, sensor and basic HMI requirements, primary characterization of naturalistic stop & go driving, and the basic approach of the transformation of situational knowledge in an elementary controller.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.11
• /
• pp.6830-6837
• /
• 2014

Since the advent of global warming and energy depletion, there has been great interest in eco-driving (energy-efficient driving). In this paper, a system is proposed to monitor the idle running of an engine and steady driving for a vehicle equipped with an ISG (Idling Stop & Go system). The system consists of a G/W device to acquire the vehicle operation data, a smartphone app for monitoring eco-driving and a server system. The main contribution of this paper is that it defines the integrated functions, the architecture and operation mechanisms of a system for monitoring eco-driving including the prohibition of running idle. The system enables the users to check the idling stop times, driving speeds, fuel savings, and $CO_2$ emissions, resulting in the driving style for eco-driving. The server system, which is a part of this system, provides OpenAPI-style web services for the storage and retrieval of car operation data, which facilitates the development of applications.