Motion Simulation And Structural Optimization Of The Key Institutions Of Aircraft Ejection Seat

As a kind of safety devices of aircraft, the ejection seat is regarded as the most reliable life-saving tool and the most widely used equipment in the air rescue. As the performance of the ejection system have a direct impact on the life safety of pilots and aircraft combat capability, it is given high regard by countries around the world. The differences of technology level are large compared with that of the foreign countries, because of our weak foundation and late start in the aviation life-saving technology.According to design requirements of the ejection seat and the basic process of ejection, the article gives a design on the structure of ejection seat and related components of life safety systems, and a three-dimensional model of key institutions of the ejection system is established using virtual technology. In accordance with aircraft flight status and matrix theory, we get the track changes rule of gravity center of the lifesaving system and the lowest life-saving height and related safety factor. Proceed with the operating principle of interlock device on the ejection seat and the working order of its agencies, we make an analysis of the reasons why ignition institution works in advance. Meanwhile, we do simulation analysis of the lock arm in using the finite element method by which we get the maximum deformation of the contact area of the lock arm as well as the strength of the weak parts. The article adopted optimal design method to design the lock arm, and got a new lock arm structure with a dynamics analysis of the new lock arm. The results showed that there is a reduction of about45%of the maximum stress on the lock arm, and the maximum deformation is reduced to0.425mm, which has achieved the purpose of optimization. Finally, the effectiveness of the structural optimization is verified by a reliability calculation on the main bearing position of the previous and improved lock arm on the base of reliability theory.The dynamic analysis and structural optimization on interlock device of ejection system has positive significance for improving the security of ejection system and the strength of lock arm, which provides a theoretical reference for the study of interlocks.