**6. Conclusions**

In this paper, an artificial satellite was simplified as multi-layer target plates based on its structural characteristics. The damage process of a kinetic projectile hitting the multilayer target plates was analyzed by integrating the experiments and finite element method. Then, the impact characteristics of the kinetic projectile on the honeycomb sandwich plate were analyzed. Finally, the influence of the initial velocities and incident angles on the damage characteristics were studied based on the simulation model.

The damage characteristics between the simulation and the test were consistent in terms of the damage range of the targets, validating the simulation model. The analytical results of the kinetic projectile impact on the honeycomb sandwich panel correlated well with the simulation; the ballistic limit velocity was determined as 150 m/s. We also found that the opening deformation had little relationship with the projectile velocity.

The projectile velocity necessary to achieve effective damage to the circuit boards without penetration of target F was between 300 m/s and 350 m/s, and we identified the most appropriate initial velocity as 325 m/s. Projectiles with a higher initial velocity had a stronger ability to penetrate the plates, but the damage area was reduced. The kinetic projectile could adapt to an incident angle less than 5◦. Due to the lateral effect, the front damage elements still moved in the vertical direction, increasing the damage area but reducing the penetration ability.

**Author Contributions:** Conceptualization, S.Y., H.Z. and Z.D.; methodology, S.Y. and Y.B.; validation, S.Y., Y.B. and W.S.; formal analysis, S.Y. and Y.B.; investigation, S.Y.; resources, Z.D. and H.Z.; data curation, Y.B.; writing—original draft preparation, Y.B.; writing—review and editing, S.Y. and G.Z.; visualization, S.Y. and Y.B.; supervision, Z.D.; project administration, Z.D. and funding acquisition, H.Z. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was supported by the National Natural Science Foundation of China (52102436), the Fundamental Research Funds for the Central Universities (30920021109), the Natural Science Foundation of Jiangsu Province (BK20200496), the China Postdoctoral Science Foundation (2020M681615), the project of Key Laboratory of Impact and Safety Engineering (Ningbo University), the Ministry of Education (CJ202107) and the State Key Laboratory of Mechanics and Control of Mechanical Structures (Nanjing University of Aeronautics and astronautics) (Grant No. MCMS-E-0221Y01).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data are contained within the article. The data presented in this study can be seen in the contents above.

**Acknowledgments:** We wish to express our gratitude to the members of our research team, Guang-fa Gao, Zhaojun Pang, Qing Lin, Weiliang Zhu, Mengsheng Li and Chunbo Wu.

**Conflicts of Interest:** The authors declare no conflict of interest.
