A particle swarm optimisation algorithm for multi-plant assembly sequence planning with integrated assembly sequence planning and plant assignment

In a multi-plant collaborative manufacturing system, the manufacturing and assembly operations for producing a product can be distributed at different plants at different locations. In this research, a multi-plant assembly sequence planning model is presented by integrating assembly sequence planning and plant assignment and is solved using a particle swarm optimisation (PSO) algorithm. In assembly sequence planning, the components and assembly operations are sequenced according to the operational constraints and precedence constraints to achieve assembly cost objectives. In plant assignment, the components and assembly operations are assigned to the suitable plants under the constraints of plant capabilities to achieve multi-plant cost objectives. A new PSO encoding scheme is presented in which a particle is defined by a position matrix defined by the numbers of components and plants. The PSO algorithm simultaneously performs assembly sequence planning of components and assignment of plants with an objective of minimising the total of assembly operational costs and multi-plant costs. The main contribution lies in the new multi-plant assembly sequence planning model and the new PSO solution scheme. An example product is tested and illustrated. The test results show that the presented method is feasible and efficient for solving the multi-plant assembly sequence planning problem.