550 / 2024-04-25 21:03:00

Design an assembly line with human-machine collaboration and moving workers

assembly line balancing,human-machine collaboration,moving worker,Dynamic Programming Algorithm

Replacing human workers in assembly lines with full-automated or semi-automated machines is popular during the COVID pandemic to reduce worker infection and production disruption. Some processes can be easily full automated, while some processes can only be performed by manual or by human-machine collaboration. Determining which processes should be automated and how to configure resources (e.g., machines, workers) in the line is essential to reduce the production cost of the line. Motivated by an industrial case in cellphone manufacturing, this study investigates an assembly line design problem where human workers may move among multiple stations to work collaboratively with different semi-automated machines. The decision maker needs to select process alternatives, and assign tasks, workers and machines to each station in order to minimize the total production cost, which is the weighted sum of the purchasing cost, the operation cost of the machines and the salary of workers. The moving time of workers must be considered and parallel stations are allowed. A mixed-integer linear programming model is formulated, and a dynamic programming procedure is proposed to solve this problem. The computational results show that the proposed algorithm can find optimal design for an assembly line with a hundreds of tasks.