Inside a naval bridge simulator in the southern coastal city of Changwon, an officer issued a sharp navigational command: "Port five degrees, hold course 330!" The voice that echoed back was not that of a young sailor, but the metallic confirmation of a humanoid robot. "Port five degrees, hold course 330," the machine repeated, its mechanical hands gripping the wheel to adjust the ship's heading before reporting completion: "Holding course 330." The Korean Navy conducted Thursday its first-ever combat experiment utilizing PIBOT, a physical artificial intelligence (AI) humanoid robot designed to replace human sailors at the helm. Developed by the Korea Advanced Institute of Science and Technology (KAIST) with 5.7 billion won ($4.1 million) in defense funding, the initiative represents a high-tech gamble to solve a looming national existential crisis: a demographic cliff that is rapidly draining the country's military recruitment pool. The simulation tested PIBOT’s ability to process verbal orders via a large language model, repeat commands to avoid miscommunication and physically manipu