Aero-engine assembly sequence planning based on discrete-time pontryagin's minimum principle

To eliminate maintenance error during aero-engine assembly, assembly sub-Petri nets is used to modeling aero-engine parts assembly sequence (PAS) based on assembly precedence relationship. By the given assembly evaluation criterion, assembly sequence planning can be transformed into optimal transition firing sequence (OFS). Discrete-time Pontryagin's minimum principle (DTPMP) is introduced to find OFS and DTPMP states that an OFS must minimize the Hamiltonian function which can be treat as the heuristic information to find the PAS. In addition, to avoid latent deadlock, the OFS algorithm is proposed. After complexity analysis, the OFS algorithm based on DTPMP is proved to be polynomial complexity.