PDO Packing Mechanism for Reducing CANopen Network Utilization

CANopen 네트워크 이용률 감소를 위한 PDO 패킹 메커니즘

  • 강민구 (아주대학교 산업공학과) ;
  • 박기진 (아주대학교 산업정보시스템공학과) ;
  • 김종철 (아주대학교 산업공학과)
  • Published : 2009.04.15

Abstract

CANopen which is one of the in-vehicle network (IVN) protocols is adopted to solve the hardware dependency problem of the CAN-based application. CANopen makes different CAN devices interoperable each others. By the advantage of the device profiling concept, it can make the period of developing CAN-based application system shorten. The utilization of CANopen network must be reduced to improve the communication performance (e.g. worst-case response time). For reducing network utilization, messages need to be packed as many as possible so that message frame overhead can be decreased. In this paper, we suggested a PDO packing mechanism using object dictionary (OD) and process data object (PDO) communication service in CANopen. Through experiments, the performance of the mechanism is evaluated with SAE benchmark. As a result, network utilization is decreased about 10% compared to the result of the previous works.

최근 각광받고 있는 차량 내부 네트워크(In-Vehicle Network)의 일종인 CANopen 프로토콜은 다양한 벤더의 하드웨어 특성에 의존적인 CAN(Controller Area Network) 기반 응용 프로그램 개발의 문제점을 해결하고자 제안되었으며, 프로파일링(Profiling) 개념을 사용하여 CAN과 이의 응용 계층인 CAL(CAN Application Layer)에서 동작하는 모든 하드웨어 장치를 지원함에 따라 CAN 기반 응용 시스템의 개발 기간의 단축이 가능하다. 메시지 처리 성능(예: 최악 응답 시간)을 높이기 위해서는 CANopen 네트워크 이용률(Utilization)을 감소시킬 필요성이 있으며, 이를 위해 가능한 많은 메시지를 패킹(Packing)하여 전송함으로써, 메시지 전송 시 발생하는 메시지 프레임의 오버 헤드를 줄이는 것이 바람직하다. 이에 본 논문에서는 CAN의 응용 계층에서 동작하는 CANopen의 OB(Object Dictionary) 및 PDO(Process Data Object) 통신 서비스를 이용하는 PDO 패킹 메커니즘을 제안하였다. SAE(The Society of Automotive Engineers)에서 제공하는 벤치마크(Benchmark) 자료를 이용하여, 본 논문에서 제안한 메커니즘의 성능을 평가하였으며, 선행 연구에 비해 CANopen 네트워크 이용률이 약 10% 가량 감소하는 것을 확인하였다.

Keywords

References

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