China is putting robots to work in real-world policing, with a traffic-control machine in Hangzhou now issuing warnings to motorists and pedestrians. Meanwhile, another Chinese robotics firm has unveiled a humanoid machine whose claimed top speed exceeds Usain Bolt’s 100-metre world-record pace.

But at a busy intersection in the eastern Chinese city of Hangzhou, the 1.88-m (6-foot-2-inch) robot can spot a helmetless e-bike rider, issue a polite warning and swing its…

A Chinese technology company is testing robot traffic officers in Hangzhou to automate repetitive road-monitoring duties. Reuters reported that the machines can detect helmetless…