Before revision: First to fix the substrate and move the cold spray gun/nozzle using a robotic arm , the second one is to move the substrate with a robotic arm, and keep the spray-gun nozzle fixed.
After revision: First to fix the substrate and move the cold spray gun/nozzle using a robotic arm ;, the second one is to move the substrate with a robotic arm, and keep the spray-gun nozzle fixed.