A four-legged robot dog named "HOUND" demonstrated unprecedented agility and speed, running the fastest 100-meter sprint speed ever achieved by a quadruped robot, and setting a new Guinness World Record in the process. The robot dog was designed and built by the Dynamic Robot Control and Design Laboratory of the Korea Advanced Institute of Science and Technology (KAIST). The 99-pound (45-kilogram) robot dog started from a standstill and ran 100 meters at an average speed of 11.26 miles (18.12 kilometers) per hour in 19.87 seconds.

HOUND is designed for high-speed movement. In addition to a running speed of 3 m/s (6.7 mph), it can run across grass, walk long distances and climb 22° slopes. Its capabilities are due to its optimized mechanical design, especially the motor controller and gear configuration.

Young-HaShin, the robot's designer, told Guinness World Records: "Transient and stable performance are important features when deciding on motors for dynamic leg movements."

The hip and knee actuator modules are one-piece structures configured in parallel, with hollow shafts used to transmit power to the joints. For the knee joint, a belt and pulley system provides a full range of motion. HOUND's developers chose a planetary gearbox system because of its high power transmission efficiency. The robot uses advanced reinforcement training simulation technology, a data-driven approach that learns optimal intelligent behavior through trial and error.

"All of these actions are achieved by a single (motor) controller trained in simulation through reinforcement training. To challenge the limits of the actuator, motor characteristics were added to the simulation to make the environment as close to the real world as possible," Shin said.

HOUND isn't the first robot to break a speed record. In 2012, the U.S. Defense Advanced Research Projects Agency's Cheetah robot (also a quadruped) set a new land speed record for robots, sprinting 20 meters (65.6 feet) at 28.3 mph (45.5 km/h), surpassing the top speed of Jamaican sprinter Usain Bolt of 27.78 mph. In 2022, Cassie, developed by Agility Robotics, completed the 100-meter dash in 24.73 seconds, setting a Guinness World Record for the fastest bipedal robot.

Although HOUND has record-breaking capabilities, it still has a long way to go before it can catch up with Bolt's 9.58-second 100-meter world record set in 2009.

The video below, produced by Guinness World Records, shows HOUND in action: