Aviation container entry/exit trajectory design

The air cargo loading system is a mission-critical system for aircraft, enabling unit load device(ULD) loading, unloading, and air transport. Various ULD have distinct methods of entering and exiting the cargo door, as well as different trajectories within the cargo hold. The movement of various types of ULD in the cargo hold, following a predetermined path, is facilitated by power-driven units(PDU) positioned in a decentralized manner within the system. Therefore, the design of the movement trajectory of the loading and unloading stage of the ULD is the fundamental input source for the layout scheme, the source of action, and the timing sequence of the power drive unit of the system. The efficiency of the ULD ground loading and unloading environment for transport aircraft can be further improved by clarifying the trajectory of the ULD in and out of the bay in advance. This paper integrates engineering principles by proposing three distinct trajectories for the ULD entering and exiting the hatch. Through simulation analysis of the loading unit's movement trajectory, a comprehensive comparison is made. It is concluded that positioning the ULD along the center line in the hatch area as it enters the cargo hold is the optimal path. This finding serves as a reliable basis for the subsequent layout of the cargo loading system and the PDU.