Photo taken on Sept. 29, 2021 shows an unmanned aerial vehicle (UAV) displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Deng Hua)

Photo taken on Sept. 28, 2021 shows an unmanned aerial vehicle (UAV) displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Deng Hua)

Photo taken on Sept. 29, 2021 shows a WZ-7 unmanned aerial vehicle (UAV) for surveillance purposes displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Liu Dawei)

Photo taken on Sept. 29, 2021 shows a Yunzhou unmanned speed boat displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Deng Hua)

Photo taken on Sept. 29, 2021 shows a ground unmanned combat platform displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Deng Hua)

Photo taken on Sept. 29, 2021 shows a WZ-7 unmanned aerial vehicle (UAV) for surveillance purposes displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Liu Dawei)

Photo taken on Sept. 28, 2021 shows an unmanned aerial vehicle (UAV) for surveillance purposes displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Deng Hua)

Photo taken on Sept. 29, 2021 shows an unmanned patrol boat displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Deng Hua)

Photo taken on Sept. 28, 2021 shows an unmanned aerial vehicle (UAV) for assault purpose displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Deng Hua)

Photo taken on Sept. 29, 2021 shows an unmanned aerial vehicle (UAV) displayed at the 13th China International Aviation and Aerospace Exhibition, or Airshow China 2021, in Zhuhai, south China's Guangdong Province. (Xinhua/Liu Dawei)

来源：Xinhua