• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.1
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• pp.17-22
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• 2013

Design of braking system is one of the most critical subjects in vehicle stability. In this paper, optimal scheme for brake force proportioning of all-wheel-drive vehicle is proposed to guarantee the vehicle dynamic stability under plausible drive circumstances. A brake force distribution of generic $8{\times}4$ vehicle is calculated according to proposed scheme and braking stability of this vehicle is verified by using a commercial vehicle software, Trucksim.

• Journal of Auto-vehicle Safety Association
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• v.12 no.2
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• pp.21-26
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• 2020

This paper presents an anti-lock braking system for commercial vehicles with pneumatic brake system by using slip ratio. By virtue of system reliability, most commercial vehicles adopt pneumatic brake system. However, pneumatic brake systems control is more difficult than hydraulic systems due to a longer time delay and the system nonlinearity. One of the major factors in generating braking forces is the wheel slip ratio. Accordingly, the proposed ABS strategy employs the slip ratio threshold-based valve on/off control. This threshold-based algorithm is simple but effective to control the pneumatic brake systems. The control performance of the proposed algorithm has been validated via simulation studies using MATLAB/Simulink and Trucksim. The results show ABS by using slip ratio reduces the braking distance and improves vehicle control.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.4
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• pp.401-407
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• 2016

For high fuel economy, many kinds of unit in vehicle have been developed. In steering system, as a result, HPS(Hydraulic Power Steering) system has been replaced as EHPS and EPS system. But the structures of these systems are totally different, and that causes the uncertainty of fuel economy evaluation. Therefore we undertake to research to find results and tendency of fuel economy and energy in steering system. For accurate evaluation, we modeled different types of steering systems on same vehicle model. The simulation came into action on various driving cycle. The driving condition is designed to show standby power of pump. Results show differences of fuel efficiency and energy consumption.

• Journal of Auto-vehicle Safety Association
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• v.14 no.2
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• pp.7-13
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• 2022

This paper presents a yaw moment control based on estimated mass for manual-shift commercial vehicles. In yaw moment controller, parameter uncertantiy of vehicle mass is important because the desired yaw moment depends on vehicle parameter. However, in the case of commercial vehicle, the weight of the loaded vehicle is more than twice as much as compared to the unloaded vehicle. The proposed algorithm estimates the vehicle mass by using the longitudinal dynamic and gear shifting characteristics. The estimated mass is used to adaptively modify the vehicle parameters. In addition, this paper estimates the chamber pressure of a pneumatic brake and generates the target yaw moment through on/off valve control. MATLAB/Simulink and Trucksim were performed under sine with dwell test. The results demonstrate that the proposed algorithm improves the lateral and rollover stability.