Spray Trajectory Planning for Complex Structural Components in Robotized Cold Spray Additive Manufacturing

In the cold spray additive manufacturing (CSAM) process, layer-by-layer stacking is an efficient method to achieve materials additive manufacturing (AM). Unlike other AM processes, such as selective laser cladding, which can quickly achieve trajectory planning by using commercial software, there is currently no general methodology for spray trajectory planning in the CSAM process. Accurate and fast generation of trajectories for each layer of the manufactured workpiece is a challenge. When a component with multiple features is manufactured, the spray paths between features cannot be created easily due to the “one-stroke” character. That is, the powder feeding cannot be interrupted during the entire spraying process. This means that for the deposition of multi-featured components, the planning of the path of the nozzle transfer from one feature to another is a challenge. If the transfer path goes directly across the area of the deposited feature, it can significantly change the shape of the deposit and cause undesired deposition results. Additionally, the spray gun or the substrate held by the robot usually needs to be deflected by a certain angle to compensate for the loss of deposit along the edges. An accurate and efficient spray trajectory planning is the most critical part of the CSAM process. Thus, this article proposes a general manufacturing methodology for complex structural components in the CSAM process. The simulation and experimental results revealed that the methodology can efficiently generate the necessary spray trajectory to fabricate the desired deposit. It makes CSAM truly possible in the manufacture of workpieces with complex geometries.