On December 27, Wes Morrill, Tesla Cybertruck’s lead engineer, posted a video showing the Unitree G1 robot training in combat exercises—a part of the humanoid robot’s motion simulation testing. The video was later reshared by Elon Musk on X (formerly Twitter). According to Global Times, the original footage appeared on China’s Bilibili platform on December 25.

In the video, the G1 follows the trainer’s instructions but accidentally kicks the trainer in a “sensitive area.” Immediately afterward, when the trainer bends over in pain, the robot repeats the action. This sequence is likely what Musk found hilarious, sharing the clip with a “laughing out loud” emoji.

“Should we rely on past science fiction ideas to build the real world?” Morrill asked. “Humanoid robot testing will be an interesting challenge.”

Morrill also noted that previously, robots were often restricted to “no-go zones” such as walls or laser fences. “This was an easy way to ensure humans weren’t injured by powerful machines. But as humanoid robots play increasingly significant roles alongside humans, these barriers need to be removed,” he wrote.

Regarding the G1’s “attack” on the trainer, Unitree clarified on December 28 that the combat exercise was a “secondary program developed by the buyer,” and the company only provides the hardware. On Bilibili, the account that posted the video explained that the G1’s mistake was related to technical latency during training, adding that the latency could be gradually reduced as algorithms improve, potentially reaching as low as 0.1 seconds.

Earlier, on December 20, Elon Musk shared another video showing six Unitree G1 humanoid robots performing at Wang Leehom’s concert in Chengdu, China, with acrobatic dance moves. “Impressive,” the American billionaire commented.

According to TechNode, Musk’s praise for the G1 is rare, as the robot is one of Tesla’s main competitors to Optimus, the humanoid robot developed by Tesla. It could also be interpreted as a rare acknowledgment from Musk of Chinese achievements in humanoid robotics.

The Unitree G1 was launched in May 2024. Standing 1.3 meters tall and weighing 35 kg, the robot is highly mobile thanks to 23–43 joint motors. In recent months, the humanoid robot has impressed observers with a variety of skills, including martial arts, acrobatics, sports, and walking naturally in public.

Unitree Robotics, founded in 2016 in Hangzhou, China, specializes in quadruped and humanoid robots. Its products are used in transportation, surveillance, scientific research, and entertainment. The company has pursued a rapid commercialization strategy, bringing robots to market with a wide range of accessible prices. Today, Unitree is considered one of Asia’s leading service and AI application robotics companies.