New Delhi, Aug. 24 -- China's humanoid robots are sprinting ahead of their rivals-quite literally. On August 17th one of their number, called Superman, clocked up a running speed of 12.66 metres per second, beating the previous record set by Usain Bolt, before crashing into a wall. The triumph only added to the buzz over Unitree, Superman's maker, which debuted its shares in Shanghai two days later. Their price leapt by 460%.

More impressive displays are expected over the coming days as the Humanoid Robot Games take place in Beijing. Yet as the ignominious end of Superman's running feat demonstrates, the technology still has a long way to go. Chinese companies are expected to sell 50,000 humanoids this year, more than triple last year's ...