A robot is seen on Mount Etna, Italy on July 4, 2017. Mount Etna, in Sicily, is a test bed for the approximately three-foot high, four-wheeled machine ahead of a future mission to the moon. It is being conducted by the German Aerospace Centre, the agency which runs Germany's space programme. (Photo by Antonio Parrinello/Reuters)

A man gestures to a robot at a restaurant in Hefei, Anhui province, December 26, 2014. The restaurant, with a space of 1300 square metres and a total of 30 robots to cook meals, deliver dishes and welcome costumers, was reported to be the biggest robot restaurant in China. (Photo by Reuters/Stringer)

Sixty four year old Hollywood movie stuntman Rock Taylor drives through a huge sheet of glass at the 02 Arena on September 13, 2011 in London, England. The stunt was performed in an attempt to break a previous Guinness record to “break through the Largest breakaway glass structure in a car”. The stunt was to mark “Remember a Charity” week, which aims to encourage more people to leave gifts to charity in their will. (Photo by Dan Kitwood/Getty Images)

Japanese toy maker Takara Tomy's world's smallest humanoid robot “i-Sobot” is displayed during the Toy Forum 2007 on January 23, 2007 in Tokyo, Japan. The 165mm height robot is able to walk, play the drums and keep its balance. (Photo by Koichi Kamoshida/Getty Images)

Humanoid robot bartender “Carl” interacts with guests at the Robots Bar and Lounge in the eastern German town of Ilmenau, July 26, 2013. “Carl”, developed and built by mechatronics engineer Ben Schaefer who runs a company for humanoid robots, prepares spirits for the mixing of cocktails and is able to interact with customers in small conversations. (Photo by Fabrizio Bensch/Reuters)

People look at a RoboThespian humanoid robot at the Tami Intelligence Technology stall at the WRC 2016 World Robot Conference in Beijing, China, October 21, 2016. The conference showcased China's burgeoning robot industry as the nation seeks to increase the use of robots in its manufacturing and service industries. (Photo by Thomas Peter/Reuters)

People try to board a goverment bus during the second day of a suspension of public transport services in Apopa, El Salvador July 28, 2015. Violent gangs in El Salvador ordered bus drivers to strike on Monday in a conflict that has killed six people and left thousands of commuters stranded on the streets of the Central American capital, police and bus company officials said. (Photo by Jose Cabezas/Reuters)

Actress Liv Tyler poses for a portrait during the 2012 Sundance Film Festival at the Getty Images Portrait Studio at T-Mobile Village at the Lift on January 21, 2012 in Park City, Utah. (Photo by Larry Busacca/Getty Images)