Study on pyroshock response of micro-satellite pyrotechnic cutter

When the micro-satellite panel is deployed in orbit, it needs to be unlocked by the pyrotechnic device. The highamplitude pyroshock environment generated in the unlocking process is fatal to the sensitive components on the satellite. Therefore, accurate and quantitative analysis of the structural response caused by the explosion can better understood the transmission characteristics of pyroshock, so that effective isolation methods can be carried out. In this paper, the finite element model of the pyrotechnic cutter is established in LS-Dyna, and the explosive unlocking process of the pyrotechnic cutter is simulated by the Particle Blast Method (PBM). The whole motion process of the cutter from unlocking to cutting off the pretightening rod is obtained, the distribution of stress and the propagation law of pyroshock wave are extracted. The results show that before unlocking, the explosion shock is the main part of the pyroshock, while after unlocking, it is mainly caused by the prestress release of the pretightening rod and the impact of the cutter hitting the cutting board. Explosive shock is the main factor affecting the near-field pyroshock, while the far-field pyroshock is mainly affected by the impact. To verify the accuracy of the simulation, a unlock test of pyrotechnic cutter are performed, the acceleration response values of the main reference points are obtained, and the results show that the two results are in good agreement in time domain and frequency domain. Based on the study of the separation characteristics, some suggestions on the optimization of damping buffer are proposed here.