OPEN-ENDED TASKS. “Robots should be capable of interacting in a cooperative and adaptive manner with their human counterparts in open-ended tasks that can change in real-time. An important aspect of the robot behavior will be the ability to acquire new knowledge of the cooperative tasks by observing and interacting with humans.”
http://www.eva.mpg.de/documents/IEEE/Lall%C3%A9e_Towards_IEEETrans_2012_1569280.pdf