The Root Cause Analysis And Application Based On The Function And Causality

In order to solve the system's invention problem,TRIZ must analyze the nature of the problem from the failure of the system,which is the root cause analysis.The existing root cause analysis methods define the insufficiency or harmful effect of the system failure by analyzing the interaction between the system components based on the system failure problem.However,these methods basically determine the root cause from the perspective of causality,ignoring the consistency between the functions of the components within the system and the development goals of the system.Therefore,this paper determines the gap between the current system and the ideal target as the basic problem by analyzing the idealized state of the system and combining the functional state of the functional model;Analyze the basic problem by the causal chain analysis and construct the causal diagram based on functional parameters by analyze the correlation between functional parameters;Construct the root conflict according to changing of independent functional parameters,and then create the function diagram of the root conflict.Through the idealized method,the function diagram of root conflict is improved and the system solution model is obtained.The main contents of this paper include the following aspects:1.Analyze the gap between the current state and the ideal state of the system to determine system problems.Combine functional analysis with causal chain analysis to analyze internal and external factors that cause system problems.Based on the correlation between functional parameters,a causal diagram based on functional parameters is established to determine the root causes of the system problem.2.Change the set value of the functional parameters to solve system problems based on the relevant functional parameters,and build system root conflicts.Establish a functional map of the root conflict,describe the nature of the root conflict,and serve as a starting point for solving the problem.3.Identify the idealized objects from the role of the system external environment and internal components and find solutions to the current problems.Idealized tools are not only idealized for system problem models,but rather for simplifying systems and improving system idealization.4.Based on the theoretical flow of this paper,the failure analysis of the double card casing joint is carried out.The root cause of the failure is determined by the surface hardness of the rear jacket,and the corresponding solution is put forward.The correctness of the analysis results is verified by the finite element analysis,which shows that the method is effective.