This paper systematically analyzes the motion characteristics of the mobile automatic lifting and landing double-arm clamping tower assembly device in soft terrain and slope environments through theoretical analysis and numerical research. First, a force model for the tracked chassis was established to analyze the nonlinear relationship between the depth of track front end sinking and ground pressure under soft soil conditions, and the influence of soil parameters on the sinking depth was explored. Next, the variation of pushback resistance under different slope angles was investigated. Finally, a model of the tower assembly device was established using RecurDyn, and slope climbing simulations were conducted to obtain the driving torque curve of the drive wheels. The results show that soil type and slope angle significantly affect track sinking depth and pushback resistance. Pushback resistance decreases with the increase of slope angle under sloped conditions. The research results provide a theoretical basis for the optimization design and enhancement of the device’s adaptability to complex terrains.