The Research of Hierarchical Synchronization Mechanism About 2-Vote-2 Safety Computer

In order to improve the safety and reliability of the safety computer of the next generation train operation control system, the safety computer using the structure of 2-vote-2 is playing an increasingly important role, and the requirements for the performance and reliability are getting higher and higher. As a real-time system, the synchronization problem of the safety computer is the key to achieving reliability. Therefore, this paper focuses on the analysis and studies on the synchronization problems of the 2-vote-2 safety computer. First of all, the structure of the 2-vote-2 safety computer is analyzed and the synchronization mechanism is designed. A new hierarchical synchronization mechanism is proposed, the bidirectional timing supervision monitor is set up between different levels to achieve the synchronization process of the 2-vote-2 safety computer. Based on this, system software uses task cycle scheduling control and dual-module communication to process the input, calculation and output tasks, synchronize in each task point of the control cycle and achieve the task synchronization. The system's model is built by UPPAAL which based on timed automata, the model is verified and the verification results showed that the designed hierarchical synchronization mechanism conformed to the requirements of design specifications.