Friendly robot "hitchBOT" was designed by experts to explore how much trust machines could place in humans by how successfully it managed to hitch rides. The robot was kitted out with GPS, a camera, 3G connectivity and speech recognition to communicate with people, to tell them where he was headed.

A trivia-loving robot built to study whether machines could trust humans managed to hitch-hike its way across Canada and parts of Europe in safety – only to be vandalized when it got to the U.S..

However, over this last weekend, two weeks into his latest adventure – a U.S. road trip that was supposed to end in San Francisco – hitchBOT was found destroyed in the city known for "brotherly love": Philadelphia, PA.

Cut short from visiting Mount Rushmore and Vegas, the research team from the Canadian McMaster and Ryerson universities, confirmed online that he had been vandalized two weeks into his journey, starting on July 17 in Marblehead, MA.

"Unfortunately, hitchBOT was vandalized overnight in Philadelphia; sometimes bad things happen to good robots," the team wrote on the hitchBOT website.

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The damage to the robot was confirmed when an image was posted on Twitter, revealing it had been vandalized with his head and arms torn off.



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The researchers added online that this "great experiment is not over" and would look into further adventures for the future.

"We have no interest in pressing charges or finding the people who vandalized hitchBOT; we wish to remember the good times, and we encourage hitchBOT's friends and fans to do the same."