How China’s hyper-realistic humanoid robot achieved its eerily human walk

XPENG’s hyper-realistic humanoid robot IRON gained widespread attention for its fluid, lifelike walking and gestures, prompting skepticism that it might be a person in a suit. To dispel doubts, an engineer publicly cut away part of its synthetic skin, revealing a metal frame and internal bionic components. Unlike other humanoid robots focused on strength or speed, IRON is designed with a “born-from-within” philosophy that replicates human anatomy through a bionic spine, artificial muscles, and soft synthetic skin. This approach emphasizes humanlike movement and appearance to create a robot that feels approachable and emotionally warm, rather than cold or mechanical. XPENG’s design philosophy centers on human-centric customization, offering potential buyers options for body types, gendered forms, and clothing, aiming to make the robot feel more personal and relatable. By carefully addressing the “uncanny valley” effect—where robots appear almost but not quite human and thus provoke discomfort—IRON uses familiar human proportions, flexible skin,