Allocation and scheduling of deposition paths in a layer for multi-robot coordinated wire and arc additive manufacturing of large-scale parts

Abstract

ABSTRACTIn multi-robot cooperative wire and arc additive manufacturing (MRC-WAAM) systems, allocating and scheduling deposition tasks is necessary. The challenge comes from the factorial computational complexity when optimising robot time, workload, and deposition order. This work presents a novel method, ‘top k%’. The main idea is to iteratively assign k% amount of paths from a warehouse to the robot having the least workload until all paths are set. A collision-free deposition process is scheduled by checking the overlapping conditions of robot swap areas. Both simulative testing and actual depositions were conducted to validate the applicability and effectiveness of the method. The results indicated that the ‘top k%’ method can facilitate the equality of robot workload and enhance the adjacency of paths. The top k% method outperforms the existing solutions concerning a reduction of turns and start-arc points, which improves the forming quality of MRC-WAAM.

Keywords

• Wire and arc additive manufacturing
• multi-robot coordination
• path allocation
• path planning
• process optimisation