Visitors learn about how honey is made at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

A child flies a drone through an obstacle ring at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

Visitors pose for an AR (augmented reality) photo at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

A child experiences facial recognition technology at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

A child experiences a VR (virtual reality) game at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

Children learn about the hydrophobicity of different surfaces at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

Children attend a chemistry workshop at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

Visitors attend an architecture engineering workshop at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

Visitors attend an architecture engineering workshop at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

Visitors participate in a game that shows how riding can reduce carbon dioxcide at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

A visitor enjoys a VR (virtual reality) game at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)

A visitor experiences a game imitating weight loss in space at the "I Love Science Festival 2019" at Brussels Expo in Brussels, Belgium, April 27, 2019. The 3-day festival opened here on Friday, with some 50 institutions, associations and universities offering fun and educational activities. (Xinhua/Zhang Cheng)