In order to improve the measurement accuracy of sensors and better evaluate the damage ability of weapons, this paper uses fractal theory to analyze the relationship between preload force and contact stiffness, calculates the contact stiffness between various components, and establishes a sensor dynamics model to obtain the relationship between various influencing factors and sensor dynamic characteristics. The model results show that increasing preload force, reducing the area of PVDF film, and reducing the thickness of PVDF film, electrode, and cover plate PET film can effectively improve the dynamic characteristics of sensors, providing a theoretical basis for subsequent sensor optimization. Finally, the accuracy of the model was verified using ANSYS finite element analysis software and shock tube calibration experiments, demonstrating its feasibility.