• International Journal of Automotive Technology
• /
• 제6권4호
• /
• pp.391-402
• /
• 2005

Despite its superior braking performance to conventional vehicles on test tracks, the performance of the ABS-equipped car seems disappointing on real highway. The poor braking performance results from questionable design of the human-machine interface(HMI) of the brake system. Force-displacement relation at the brake pedal has a strong effect on the braking performance. Recently developed brake-by-wire (BBW) system may allow us to tailor the force feel at the brake pedal. This study aims at exploring analytical ways of designing human-machine interface of BBW system. In this paper, mathematical models of brake pedal feel for electro-hydraulic BBW (EH-BBW) system are developed, and the braking motion and the characteristics of the driver's leg action are modeled. Based on the dynamic characteristics of the brake pedal and the driver, two new HMI designs for EH-BBW system are proposed. In the designs, BBW system is modeled as a type of master-slave teleoperator. The effectiveness of the proposed designs is investigated using driving simulation.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2006년도 춘계학술대회논문집
• /
• pp.982-987
• /
• 2006

In general, the braking system of high speed train has an important role for the safety of the train. To stop safely the train at its pre-decided position, it is necessary to combine property the various brakes. Generally high speed train has adopted a combined electrical and mechanical (friction) braking system. Electrical brakes are consist of rheostatic brake, regenerative brake and eddy current brake and mechanical brakes are composed of disc brake, wheel disc brake and tread brake. In this paper, we introduce braking performance analysis and inspection though simulation and research to reduce braking distance.

• 자동차안전학회지
• /
• 제12권2호
• /
• pp.21-26
• /
• 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.

• 자동차안전학회지
• /
• 제16권2호
• /
• pp.14-19
• /
• 2024

This paper describes autonomous emergency braking systems (AEB) for elderly drivers designed to consider their driving characteristics. With aging, perception-reaction time, and decision-making time increase accordingly. Without being aware of these performance degradations, however, changes in driving patterns due to increased alertness while driving lead to vehicle crashes. Therefore, it is necessary to develop an autonomous emergency braking system by incorporating the characteristics of the elderly driver. In order to enhance the driver acceptance of older people, perception-reaction time, alertness, and ride comfort need to be considered for conventional autonomous emergency braking systems (C-AEB). Proactive AEB(P-AEB) algorithm has been proposed to reflect human factor of elderly driver above. The performance of the proposed algorithm has been evaluated through MATLAB simulink simulation studies. It has been shown from the computer simulations that the proposed P-AEB algorithm enhances the driver acceptance of older people by improving ride comfort while ensuring safety of vehicle.

• 한국정보전자통신기술학회논문지
• /
• 제5권4호
• /
• pp.191-197
• /
• 2012

본 연구는 공기제동의 문제점을 보안하기 위한 유지보수와 환경문제, 효율성, 경제성 등을 개선하기 위하여 정지에서 고속영역까지의 전 영역에서 전기제동을 사용하는 방법이 제시되었다. 전기적으로 완전제동을 위한 2가지 방법으로 인버터 출력전압의 증대에 의한 방법과 전동기와 인버터 사이에 직렬저항을 삽입하는 방법을 통하여 경제적이며 실제 적용이 가능한 제어방법인 직렬저항을 삽입하는 방법을 적용하기로 하였다. 직렬저항에 의한 전력손실을 감소시키기 위한 직렬저항을 단락하는 방법을 사용하여 효율을 개선하고 전영역에서의 제동력확보는 실험환경 내에서 우수한 인버터의 단자전압을 상승시키는 방법과 동일한 특성을 보였다.

• 전력전자학회논문지
• /
• 제15권4호
• /
• pp.335-341
• /
• 2010

전기제동 시스템(Electric braking system)은 기존 자동차 시스템에서 사용된 유압 브레이크를 대신하여 전동기를 이용하여 제동력을 얻게 된다. 전기제동은 기존 유압식에 비해 부품의 수가 감소되며 ABS, ESC 등의 응답성 향상 및 제동거리 감소효과를 얻을 수 있다. 본 논문에서는 EMB(Electro-Magnetic Brake)용 BLAC 전동기의 제어기를 개발하였다. 제어 시스템은 BLAC 전동기 구동을 위한 전력변환장치와 속도제어를 위한 디지털제어기로 구성되었으며, 빠른 토크 응답특성을 위해 벡터제어 기법을 적용하였다. 또한 Matlab/Simulink를 이용한 시뮬레이션 및 실험 결과를 제시하여 EMB용 BLAC 전동기의 성능을 검증하였다.

• 한국자동차공학회논문집
• /
• 제5권1호
• /
• pp.195-206
• /
• 1997

In this study, a simulation tool is developed in order to investigate non steadystate cornering performance of 4WD/4WS vehicles. The 4WD/4WS vehicles are modeled as a 8-th order dynamic system which includes complex non-linear vehicle dynamics and tire models. The vehicle models are constructed into a modulated simulation tool and are utilized for analyzing cornering performance such as combined braking and steering, cornering on the icy read and $\mu$-split braking, The whole analysis is done with the simulation tool which consists of a number of subsystems and offers graphic environment. Simulation results show that this tool is useful and cost-effective in the dynamic analysis of the combustion-engine vehicles as well as electrically driven vehicles.

• 자동차안전학회지
• /
• 제3권2호
• /
• pp.28-33
• /
• 2011

This paper presents driving path estimation algorithm for adaptive cruise control system and advanced emergency braking system using multi-sensor fusion. Through data collection, yaw rate filtering based road curvature and vision sensor road curvature characteristics are analyzed. Yaw rate filtering based road curvature and vision sensor road curvature are fused into the one curvature by weighting factor which are considering characteristics of each curvature data. The proposed driving path estimation algorithm has been investigated via simulation performed on a vehicle package Carsim and Matlab/Simulink. It has been shown via simulation that the proposed driving path estimation algorithm improves primary target detection rate.

• 한국공작기계학회논문집
• /
• 제12권1호
• /
• pp.84-91
• /
• 2003

The equipment of textiles let off is a part of inspection machine which inspects finished textiles and it checks up textiles through that. This study suggests a method to select the capacity and initial gas pressure of accumulator to control surge rising pressure occurring when suddenly braking action to a desired degree. An accumulator in hydraulic systems is by hydraulic machinery which stores kinetic energy of inertia body during braking. A series of computer simulations were done for the brake action The results of the simulation work were compared with those of experiments.

• 대한기계학회논문집A
• /
• 제33권11호
• /
• pp.1294-1299
• /
• 2009

The Korean tilting train called Hanvit 200 was launched recently in Korea to improve train speed up to 200 km/h at conventional lines. In this paper, we propose a HILS system for simulations of mechanical braking of the Hanvit 200 train using actual ASCU, actual dump valves, Simulink, dSPACE board, and ControlDesk software. In the proposed HILS system, dynamics of wheelsets, bogies and car body, brake force generation, creep force generations are realized via mathematical models, and anti-skid logic is realized using actual components. The validity of the proposed HILS system is demonstrated via comparing results of real-time and off-line simulations.