Recent studies illuminate the skills robots need if they are to get along with humans.

When a box-like robot called TUG went to work in hospitals carrying drugs between wards, the robot’s inability to tell if it was a good time to interrupt and announce its presence was a big problem for some staff members, who lashed out and kicked TUG in frustration.

“If you are going to design robots with human-like capabilities you have to design the appropriate social behavior that goes along with it,” said Bilge Mutlu of the University of Wisconsin, Madison, who studied how hospital workers got along with TUG.