http://www.sciencemag.org/news/2018/07/watch-robot-hand-learn-manipulate-objects-just-human-hand

A 5-year-old can tie their shoelaces, but robot hands aren’t nearly so nimble. A new system, however, has greatly improved their dexterity.

Hard-coding a robot to coordinate multiple joints is daunting. So computer scientists have turned to machine learning, a field of artificial intelligence (AI) in which computers build skills on their own. Such learning takes time and repetition, however, and robot hardware is slow and breakable. Some researchers instead train algorithms with virtual robots, but reality is always slightly different from simulation.