Two competitors of drones race talk during the Drone Days 2017 in Lausanne, Switzerland, Sept. 3, 2017. The three days Drone Days 2017 including drones race, robotics showcase and flying trials concluded on Sunday, which drew more than 5,000 visitors to attend. (Xinhua/Xu Jinquan)
Drone Days 2017 concludes in Lausanne, Switzerland
Source: Xinhua| 2017-09-04 10:34:46|Editor: Song Lifang