Systematic Approach for Scheduling of Tasks and Messages under Noise Environment

Nowadays, control systems consist of smart sensors, smart actuators, and controllers connected via fieldbus. Some devices such as motors in plant environments generate high degrees of EMI or noise. This noise may cause communication errors and make the successful transmission of data longer. Therefore, the noise condition has to be considered at the design of a reliable control system based on a network. This paper presents a scheduling method of task and message to guarantee the given end-to-end constraints under noise environments. A noise model with multi-sources of noise is used, and the analysis method of message's response time is presented when the noise model is applied to CAN (Controller Area Network). Two kinds of noise models are applied to an example system, and the effect to each control loop's end-to-end response time is analyzed. We believe that the proposed method help system designers design the control system guaranteeing its requirements under noise environment.

[1]  Wook Hyun Kwon,et al.  Network conscious design of distributed real-time systems , 1998, J. Syst. Archit..

[2]  A.-M. Deplanche,et al.  Heuristic techniques for allocating and scheduling communicating periodic tasks in distributed real-time systems , 2000, 2000 IEEE International Workshop on Factory Communication Systems. Proceedings (Cat. No.00TH8531).

[3]  Hans A. Hansson,et al.  Response time analysis under errors for CAN , 2000, Proceedings Sixth IEEE Real-Time Technology and Applications Symposium. RTAS 2000.

[4]  Alan Burns,et al.  Preemptive priority-based scheduling: an appropriate engineering approach , 1995 .

[5]  David Lorge Parnas,et al.  Scheduling Processes with Release Times, Deadlines, Precedence, and Exclusion Relations , 1990, IEEE Trans. Software Eng..

[6]  Richard Gerber,et al.  Guaranteeing Real-Time Requirements With Resource-Based Calibration of Periodic Processes , 1995, IEEE Trans. Software Eng..

[7]  Andy J. Wellings,et al.  Analysing real-time communications: controller area network (CAN) , 1994, 1994 Proceedings Real-Time Systems Symposium.

[8]  John A. Clark,et al.  Holistic schedulability analysis for distributed hard real-time systems , 1994, Microprocess. Microprogramming.

[9]  Joseph Y.-T. Leung,et al.  On the complexity of fixed-priority scheduling of periodic, real-time tasks , 1982, Perform. Evaluation.

[10]  Zhang Wei,et al.  EMI in hydropower plant and EMC design for its computer monitoring and control system , 2002, 2002 3rd International Symposium on Electromagnetic Compatibility.