According to the American Fun Project website on the 18th, at the 22nd Sangju Persimmon Cake Marathon held in Gyeongsangbuk do, South Korea recently, the quadruped walking robot "RAIBO2" developed by the Korean Academy of Science and Technology completed a marathon of 42.195 kilometers in 4 hours, 19 minutes, and 52 seconds. This is the world's first quadruped robot to complete a full marathon, demonstrating its ability to stably perform tasks such as delivery and patrol in complex urban environments. The marathon has an altitude increase of 50 meters at both 14 kilometers and 28 kilometers. In order to enable RAIBO2 to tackle these challenges, the team used reinforcement learning algorithms to develop a walking controller and utilized the RaiSim application to simulate complex terrains such as slopes, stairs, and icy roads for training RAIBO2. Walking involves complex interactions between strength and movement. When the robot's feet touch the ground, every step generates a strong impact force. These repeated impacts can generate vibrations and stresses, damaging the mechanical components of the robot. Therefore, walking robots must adopt highly complex systems to withstand the periodic vibrations generated by frequent impacts when in contact with the ground. The joint design of RAIBO2 is highly innovative, cleverly utilizing the energy generated during downhill driving to improve overall walking efficiency and compensate for the energy consumed during uphill driving. In the future, RAIBO2 will also add automatic navigation function, which will greatly demonstrate its capabilities in monitoring and disaster management. (New Society)