Planetary gear systems in industrial equipment, characterized by highly integrated structures, non-stationary operating conditions, and heavy-load characteristics, result in significant attenuation of fault-related vibration features, severely limiting the effectiveness of fault diagnosis. Traditional studies often use periodic modulation terms, such as the Hanning window function, to approximate the spatiotemporal distribution characteristics of meshing forces. Although these methods can effectively extract global vibration features of healthy gears (such as meshing frequency and its harmonics), they have significant limitations and are unable to analyze the nonlinear diffusion process of fault impacts through complex paths, resulting in distortion in the phase delay and amplitude attenuation patterns of fault impacts. To address these issues, this study investigates the vibration transmission characteristics of a planetary gearbox through rigid-flexible coupling simulation analysis, focusing on the transmission delay effects of impact responses to the vibration sensors at different housing locations. The study qualitatively clarifies the intrinsic relationship between transmission delay characteristics of the gear-sensor spatial relationship, providing a theoretical foundation for accurate analysis of vibration signals in planetary gear sets. The research highlights the significant spatiotemporal characteristics of the vibration responses when the fault collisions occur at different locations during the rotation and revolution of planet gears.