A fair-goer plays table tennis with a table tennis robot at Omron's stand of the Hanover Messe 2017 in Hanover, Germany, on April 24, 2017. The Hanover Messe started on Monday, and will last until April 28. More than 6,500 exhibitors from 70 nations and regions are presenting technologies for tomorrow's factories and energy systems in an action-packed industrial technology showcase themed "Integrated Industry -- Creating Value". (Xinhua/Shan Yuqi)