Why Its Nearly Impossible to Build a Robot Without China

Japan led the world in robotics for decades.More than 50 years ago, Japanese researchers captured imaginations with the first robot capable of grasping objects and walking on two legs.In 1984, a team in Japan built one that could read sheet music and play the piano.

When Honda unveiled its first humanoid in 2000, it seemed to cement the country’s lead.But now, just as tech investors, start-up founders and government officials around the world are betting that artificial intelligence will spur growth for robots, that lead no longer belongs to Japan.It belongs to China.Last month at the Humanoids Summit, a robotics conference in Tokyo, what could have been a victory lap for an industry built on decades of development and investment instead centered on a different topic: how Japanese companies can break through in a market increasingly dominated by Chinese rivals.Investors urged Japanese companies to find niches where they could compete even if they couldn’t match Chinese firms on price.A dancing robot from China’s Unitree Robotics drew the largest crowds.

Two Japanese firms also used Unitree robots to demonstrate their software....