In this May 14, 2016 photo, children wearing their school backpacks climb on a cliff using a bamboo ladder on their way home from school in Zhaojue county, southwest China's Sichuan province. A village in China's mountainous west where schoolchildren must climb an 800-meter (2,625-foot)-high bamboo ladder secured to a sheer cliff face may get a set of steel stairs to improve it's safety. (Photo by Chinatopix via AP Photo)

A man admires a sculpture in the series entitled 'Circle of Animals/Zodiac Heads' by Chinese artist Ai Weiwei in the courtyard of Somerset House on May 11, 2011 in London, England. The installation comprises of 12 bronze heads of animals which feature in the Chinese zodiac. The artist Ai Weiwei, who is outspoken in his criticism of the Chinese administration, was detained by authorities in Beijing on April 3, 2011 and his whereabouts remain unknown.

HRP-4C, a five-foot humanoid robot developed at Japan's National Institute of Advanced Industrial Science and Technology, sings and dances with performers at the Digital Contents Expo in Tokyo on October 17, 2010. The robot runs entertainment software called Choreonoid, a name formed from the words “choreograph” and “humanoid”. (Yoshikazu Tsuno/AFP)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)

German KUKA Robotics' robot LBR iiwa demonstrates a flower arrangement at the International Robot exhibition in Tokyo, Wednesday, December 2, 2015. (Photo by Shizuo Kambayashi/AP Photo)

Students from Vida Nueva School present their dinosaur robot built with recycled materials during the annual robotics fair supported by the Bolivian Education Ministry in La Paz, August 10, 2015. (Photo by David Mercado/Reuters)

Japan's On-Art Corp's eight metre tall dinosaur-shaped mechanical suit robot “TRX03” performs during its unveiling in Tokyo, Japan November 10, 2016. Stomping and roaring dinosaurs took to the stage in Tokyo on Thursday as part of a presentation for a proposed entertainment park where visitors will be able to see the realistic replicas first-hand. Japanese firm ON-ART Corp. unveiled man-operated robotic models of raptors, an allosaurus and a tyrannosaurus rex, in a performance at a hotel hall. (Photo by Toru Hanai/Reuters)

Japan's ON-ART Corp's staff repaints the company's eight metre tall man-operated walking dinosaur robot “TRX03” at the company's studio in Tokorozawa, Japan, December 6, 2016. (Photo by Toru Hanai/Reuters)