• 한국자동차공학회논문집
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• 제24권4호
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• pp.487-494
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• 2016

In order to comply with the Federal Motor Vehicle Safety Standard(FMVSS) No. 208 that has been in force since September 2003, an automatic airbag suppression system has become an essential option for detecting and protecting infants and children seated in the front passenger seat of vehicles in the U.S. market. MOBIS has developed the world's first weight-based OCS under the name NWCS. NWCS is composed of two sensors and ECU. It is sub-packaged in order to minimize the seat structure deviation. In this paper, technical features, robustness and performance of NWCS are summarized and discussed.

• 제어로봇시스템학회논문지
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• 제16권6호
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• pp.546-552
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• 2010

As the demands for the safety and convenience applications of the vehicles increase, the data load for the In-vehicle Network has increased significantly. As a result, a deterministic and fault-tolerant communication system is required to implement the safety critical applications such as X-by-wire systems. FlexRay communication system is a new standard of network communication system which provides the high speed serial communication, time triggered bus and fault tolerant communication between electronic devices. In addition to time-triggered communication, as providing of the event-triggered communication such as CAN, FlexRay protocol is able to manage the restricted communication resource more effectively. This paper presents the development of FlexRay driver which will be applied to the future ECU's communication system. To develop the FlexRay driver, the FlexRay requirement specification and FlexRay specification is analyzed. The developed FlexRay driver is implemented by using MPC5567 microprocessor of the Freescale semiconductor. To verify the developed FlexRay driver, the waveform of the FlexRay driver was measured and compared with the CAN communication system. As a result, the bus load is reduced about 13% compared with the CAN communication system.

• 전기학회논문지
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• 제63권11호
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• pp.1551-1558
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• 2014

We propose a multi-rate sensor fusion of vision and radar using Kalman filter to solve problems of asynchronized and multi-rate sampling periods in object vehicle tracking. A model based prediction of object vehicles is performed with a decentralized multi-rate Kalman filter for each sensor (vision and radar sensors.) To obtain the improvement in the performance of position prediction, different weighting is applied to each sensor's predicted object position from the multi-rate Kalman filter. The proposed method can provide estimated position of the object vehicles at every sampling time of ECU. The Mahalanobis distance is used to make correspondence among the measured and predicted objects. Through the experimental results, we validate that the post-processed fusion data give us improved tracking performance. The proposed method obtained two times improvement in the object tracking performance compared to single sensor method (camera or radar sensor) in the view point of roots mean square error.

• 한국자동차공학회논문집
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• 제22권4호
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• pp.89-97
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• 2014

As the digital control technologies in automotive industry have advanced, electronic control units(ECUs) play a key-role to improve system performance. Transmission control unit(TCU) is a shifting controller for automatic transmission of which major functions are to determine the shift and manage the shifting process considering the various sensor signal on transmission and driver's commands. As with any ECU in vehicle, TCU performs complex algorithms such as shift control, diagnostic and failsafe functions. However, firmware design analysis is hardly possible by the reverse engineering due to code protection. Transmission simulator is a hardware-in-the-loop simulator which enables TCU to work in normal mode by simulating the electrical signal of TCU interface. In this research, diagnosis and failsafe algorithm implemented on commercialized TCU is analyzed by using the transmission simulator that is developed for wheel loader construction vehicle. This paper gives various experimental results on the proportional solenoid current trajectories for different operating modes, error detection criterion and limphome mode gears for all the possible cases of clutch malfunction. The derived results for conventional TCU can be applied to the development of inherent TCU algorithms and the transmission simulator can also be utilized for the test of TCU to be developed.

• 정보보호학회논문지
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• 제33권2호
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• pp.325-336
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• 2023

자율주행 기술이 발전함에 따라 차량에 탑재되는 외부접점 센서의 수가 증가하고 있으며 특히 차량용 초음파 센서는 버스 토폴로지 형태로서 LIN 프로토콜을 사용하여 연결되며 주변을 감지하고 상태 메시지를 전송하여 차량 내부 네트워크에 접근한다. LIN은 프로토콜의 보안성이 검증되지 않아 공격에 취약하기 때문에 안전성을 평가하기 위한 테스트가 필요하지만, 물리적인 제약으로 인해 실제 차량을 이용한 분석에 한계가 있으며 이를 위한 테스트 환경이 부족하기 때문에 테스트에 어려움이 있다. 따라서, 본 논문에서는 LIN 프로토콜 분석 및 테스트를 위해 CAN과의 연동 분석이 가능한 테스트베드를 개발하고 초음파 센서를 이용하여 그 효용성을 검증하였다.

• 한국자동차공학회논문집
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• 제6권2호
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• pp.155-167
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• 1998

The prevalence of microprocessor-based controllers in automotive systems has greatly increased the meed for tools which can be used to validate and test control systems over their full range of operation. The objective of this paper is to develop a real time simulator of an anti-lock braking system and the methodology of using hardware-in-the-loop simulation based on a personal computer. By use of this simulator, the analyses of a commercial electronic control unit as well as the validation of the developed control logics for ABS were performed successfully. The simulator of this research can be traction applied to development of more advanced control system, such as traction control systems, vehicle dynamic control system and so forth.

• 전기학회논문지
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• 제57권2호
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• pp.208-213
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• 2008

In order to assess the reliability of the electronics control unit for vehicles, accelerated life test model and procedure are developed. By using this method, failure mechanism and life distribution are analyzed. The main results are as follows : i) the main failure mechanism is degradation failure that is, junction destruction of a semiconductor resin by high temperature. ii) the life distribution of the electronics control unit for vehicles is fitted well to Weibull life distribution and the accelerated life model of that is fitted well to Arrhenius model. iii) at the result of the life distribution, accelerated life test method is developed, and test time for life assessment will be shortened by 5,000 hours by this test method.

• 한국자동차공학회논문집
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• 제7권5호
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• pp.194-205
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• 1999

The prevalence of microprocessor-based controllers in automotive systems has greatly increased the need for tools which can be used to validate and test control systems over their full range of operation. The objective of this paper is to develop a real time simulator of traction control system by the methodology of using hardware-in-loop simulation based on a personal computer. By use of this simulator, the analysis of commercial electronic control units and components for TCS were performed successfully. The simulator of this research can be applied to development of more advanced control systems(suck as vehicle dynamics control system) and other automotive system.

• 대한토목학회논문집
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• 제30권5D호
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• pp.443-451
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• 2010

본 연구는 실시간 차량정보를 이용한 안전권고속도의 산정방안에 대한 연구이다. 여기서 실시간 차량정보는 모든 차량에 ECU 수집장치를 탑재하고 끊김없는 무선 통신이 이루어짐에 따라 운전자에게 제공할 수 있는 유용한 정보이다. 이러한 실시간 차량정보를 기반으로, 도로노면정보가 실시간으로 센싱될 경우에 유용한 안전권고속도 모형을 개발하였다. 여기서, 안전권고속도는 "A단일 구간에 대한 시간적 흐름에 따른 교통환경 및 도로노면상태 변화에 따른 안전 속도"로 정의하였고, 차량간의 안전거리, 통계적 차량속도, 노면상태 정보를 기반으로 그 값을 산정하도록 모형을 개발하였다. 이후, 미시적 시뮬레이터인 VISSIM을 기반으로 교통상황(원활, 정체), 유고상황(미발생, 발생), 노면상태(건조, 습윤, 적설)에 따른 권고속도의 관계를 살펴보았다. 12가지의 시뮬레이션 시나리오의 결과로 3가지 변수와 권고속도는 유의한 관계성과 그 추세를 확인할 수 있었다. 본 안전권고속도 모형에서는 안전권고속도가 평균속도보다 높게 유지하도록 하나 유고의 발생, 노면상태의 변화에 따라 실시간으로 안전속도를 변화하도록 제시하고 있다. 이러한 연구는 향후 스마트하이웨이와 같은 도로에서 운전자들이 제공받을 수 있는 도로교통과 IT가 융합된 중요한 서비스로 기대되는 바이다.

• Journal of Biosystems Engineering
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• 제37권4호
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• pp.225-232
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• 2012

Purpose: Accurate monitoring of information from various agricultural vehicles is one of the most important factors for appropriate management strategy of field operations. While there has been a number of study and design on applications of sensors and actuators for data acquisition and control system in tractor, incompatibility between various customized hardware and software has become a major obstacle to the universal deployment in real field operation. International standard for implementation of electronic control unit (ECU) in agricultural vehicles has becoming a mandatory requirement for inter-operation compatibility in the international trade of agricultural vehicle industries. The ISO 11783 standard is basically based upon well known communication technology designated using the controller area network (CAN) bus. While CAN bus could provide 1.0 Mbps of communication speed, the standard only recommended 250 kbps. Methods: This study presents the implementation and evaluation of ISO 11783 for tractor electronic control units (TECU)with a higher transmission rate from multiple ECU than 250 kbps. Throughput and loss rate of the developed prototype were calculated across manipulated bus load for laboratory experimental tests, and the maximum requirement of transmission rate by ISO 11873 was satisfied with lower than 60% of bus load. Results: Field tests with a TECU implemented to process messages from global positioning system (GPS) receiver resulted that the root mean square error of position information was lower than 4 m with 0.5 m/s as a travelling speed. Conclusions: Results of this study represent the utilization of the international standard ISO 11783 to providepractical developments in terms with the inter-operability of TECU.