An officer wipes sweat off the face of a Chinese People's Liberation Army (PLA) honor guard soldier as they rehearse for a welcoming ceremony for New Zealand's Governor-General Sir Jerry Mateparae at the Great Hall of the People in Beijing, Tuesday, July 21, 2015. (Photo by Mark Schiefelbein/AP Photo)

Italian disabled dancer Simona Atzori (top) performs, before a special audience with disabled athletes led by Pope Francis, in Paul VI hall at the Vatican October 4, 2014. (Photo by Tony Gentile/Reuters)

A prototype battery-powered plane, called Greased Lightning or GL-10 is pictured flying at NASA's Langley Research Center in this undated handout photo obtained by Reuters May 1, 2015. The plane, which has 10 engines and can take off like a helicopter and fly efficiently like an aircraft, is currently in the design and testing phase. (Photo by Reuters/NASA)

A receptionist dinosaur robot performs at the new robot hotel, aptly called Henn na Hotel or Weird Hotel, in Sasebo, southwestern Japan, Wednesday, July 15, 2015. From the receptionist that does the check-in and check-out to the porter that’s a stand-on-wheels taking luggage up to the room, the hotel, that is run as part of Huis Ten Bosch amusement park, is “manned” almost totally by robots to save labor costs. (Photo by Shizuo Kambayashi/AP Photo)

Bikers push their motorbikes during a traffic block as they take part in the “Enduropale” motorcycle endurance race on the beach of Le Touquet, northern France, February 1, 2015. About 1100 motorbike and 600 quad bike riders descend on Le Touquet every year for the racing endurance event. (Photo by Pascal Rossignol/Reuters)

Armed forces veteran Frank Simpson at the Portico library being camouflaged by body artist Carolyn Roper in Manchester, UK on May 16, 2016 as part of the #CountThemIn campaign launched on Monday by the Royal British Legion. (Photo by Jon Super/Royal British Legion/PA Wire)

Hot air balloons fly over the sky in Chiang Mai province, northern Thailand, December 6, 2014. The two-day International Balloon festival 2014 featuring balloon pilots from Germany, Spain, Netherlands, Britain, and Czech Republic is held on December 06-07 2014 to celebrate Thai King Bhumibol Adulyadej's 87th birthday and also aimed to promote the tourism industry in Chiang Mai northern city. (Photo by Pongmanat Tasiri/EPA)

The Mercedes-Benz F015 Luxury in Motion autonomous concept car is shown on stage during the 2015 International Consumer Electronics Show (CES) in Las Vegas, Nevada January 5, 2015. (Photo by Steve Marcus/Reuters)