For now, drones in the manufacturing industry are being developed to pick, arrange and load stuff in the warehouses. This may appear simple but it is a complex task in itself seeing that it’s an unmanned vehicle executing all of these tasks.
To summarize, drones aren’t involved directly in the manufacturing process and only play an indirect role for now. However, with technology progressing rapidly and with research being conducted on these points as well, the day when drones will start aiding directly in manufacturing goods isn’t far away.