Combining heuristics for tool-path optimisation in material extrusion additive manufacturing

Building time is an important issue in material extrusion additive manufacturing. The extrusion head must stop and jump from one point to another to start a new deposition. The length of the head repositioning can be reduced by applying optimisation during path planning. This work presents two optimisation algorithms, one based on the greedy option and one that combines the heuristics known as the nearest insertion (NI) and the 2-opt. The proposed algorithms are quite simple to implement and the main filling steps in the material deposition process have been mapped and considered in the analysis. The results show that it is possible to reduce considerably the repositioning distance with the proposed methods, and that the NI method usually outperformed the greedy method. It was also observed that the result was affected by the geometry of the part being analysed.