An improved discrete pigeon-inspired optimisation algorithm for flexible job shop scheduling problem

The pigeon-inspired optimisation (PIO) algorithm, which is a new promising optimisation algorithm, has successfully solved many continuous optimisation problems. In the literature, however, little research has been conducted on its application to the combinational optimisation problems. This paper therefore tries to fill in this gap and applies the PIO algorithm to solve the flexible job shop scheduling problem (FJSP), which is a typical combinational optimisation problem. It proposes an improved discrete PIO (IDPIO) algorithm to minimise the makespan of FJSP and develops methods to optimise the time to carry out the map and compass operator or the landmark operator with the PIO. The discrete map, compass operator, and the discrete landmark operator are developed respectively. The experiment results show that the IDPIO algorithm can solve the FJSP effectively and efficiently.