Fault tree analysis (FTA) is a deductive failure analysis method from top to bottom, which uses Brin logic to combine low order events to analyze the states that do not want to appear in the system. Fault tree analysis is mainly used in the field of safety engineering and reliability engineering to understand the causes of system failure and to find the best way to reduce the risk or to confirm the incidence of a safety accident or a specific system failure. Fault tree analysis is also used in aerospace, nuclear power, chemical processes, pharmaceutical, petrochemical and other high-risk industries, as well as in other areas of risk identification, such as failure of social service systems. Fault tree analysis is also used in software engineering, in debugging, and is related to the technology of eliminating the cause of the error.

On the 2020 IEEE 23rd International Conference on Intelligent Transportation Systems (ITSC), P. Gao et al^[1] published the research on the safety function of the ATP system (a control system of the communication-based train control system), they proposed a new analysis method for the ATP system, the Dynamic Fault Tree analysis method. The Dynamic Fault Tree is a system of methods for evaluating the reliability and safety of a complex system, it is also a kind of deductive method, which is based on the fault event and is analyzed step by step according to the top-down sequence through certain logical reasoning steps until the result is reached. The Dynamic Fault Tree analysis method is devoted to modeling the fault logic according to the dynamic fault behavior, and conforms to the functional design of signal system. It is worth mentioning that logical analysis based on the Dynamic Fault Tree analysis method method often analyzes the emergence of problems at the same time, instead of analyzing it layer by layer, it can greatly improve the efficiency of problem solving.

In the aerospace field, the broader term "system failure state" is used to describe the fault tree between the state that does not want to appear at the bottom and the failure event at the top. These states are classified according to the severity of their results. Results the most serious state needs the most extensive fault tree analysis to deal with. Such "system failure states" and their classification were previously addressed by functional hazard analysis.

The order of problem solving based on the Dynamic Fault Tree analysis method is:

The order of problem solving based on the Dynamic Fault Tree analysis method is:

1.

Identify the possible fault events.

2.

According to the possible fault events, establish the analysis process of them. 3.

Through the control system(just like the ATP control system), analyze whether the fault events occur. 4. If the fault events occur, solve them through the control system(just like the ATP control system).