Safety Analysis And Research Of Equipment Control System In The Rreatment Room Of Particle Radiotherapy

Currently,proton heavy ion radiotherapy is a major frontier hotspot in the medical physics community.Based on the requirements of the particle radiotherapy treatment process,patients have to align the lesion precisely with the beam stream under the automatic operation of the treatment room equipment.The safe operation of the treatment room equipment control system is the basis f or achieving precise radiotherapy and is the key to ensuring safe patient treatment.There are many different types of equipment in the treatment room,complex operation logic and the safe operation of the control system is very demanding,but there are of ten failures during testing and use,and there are huge potential risks for safe radiotherapy.At present,there is a lack of comprehensive and accurate safety analysis and evaluation in the use of treatment room equipment,and the current safety analysis methods are difficult to cope with such highly complex,software-intensive,and high safety requirements of the control system.In this paper,based on the project "Research on the control system of treatment room in Wuwei Heavy Particle Center",the group explores a practical framework for the control system of treatment room equipment in particle radiotherapy by combining relevant safety standards and Model-based Systems Engineering(MBSE)ideas.A practical framework for control systems in particle radio therapy.A comprehensive safety analysis is conducted from the system development stage to the application stage,and the system failure problems caused by logic ambiguity and software load regulation in the treatment room equipment control system are inve stigated and optimized.Firstly,from the system development stage,we propose a positive iterative analysis of the system by tracing the relationship in the modeling process,and propose a control logic optimization method with "state" as the core;second ly,we analyze the system software reliability separately,and propose a model-based reliability calculation method and optimization strategy to solve the software load distribution.Finally,by constructing a system security model and generating security analysis results,the system is reverse verified in the application stage.This paper completes the comprehensive safety analysis and research of the system,and fills the gap in the field of safety analysis of treatment room equipment control system.The main contents and innovations of this paper are as follows:(1)Introducing the MBSE idea in the safety study of particle radiotherapy treatment room equipment control system to solve the problems of inaccurate information transfer and difficult safety ana lysis and optimization process in the traditional system study;(2)Exploring the modeling method applicable to the development stage of the treatment room equipment control system,starting from the requirements and focusing on the functions,gradually refining the system from the outside to the inside,and sorting out and optimizing for the control logic.The safety and practicality of the system are improved based on solving the system failure problems caused by the control logic;(3)Apply the model-based software reliability calculation method to the system failure problems caused by software load regulation,complete the calculation and optimization of the system software,and provide a reference basis for the subsequent development and maintenance of the system;(4)In the system application stage,the model-based safety analysis technique is applied to generate FTA and FMEA safety assessment results,and the causes of system failure are summarized and corresponding optimization suggestions are formula ted.It solves the problem that the traditional safety analysis methods are too subjective and the assessment results are not accurate.The research results of this paper can contribute to the optimization of the control system of treatment room equipment,and the corresponding safety analysis results and optimization suggestions can be converted into the safety requirements of the system and improve the quality of the system.