Our hands are a pretty major feat of evolution (opposable thumbs! dexterity!), and it's hard to artificially replicate everything they can do. Especially when it comes to super fine motor skills like picking up very flat, thin or small objects. As part of DARPA's ARM program, iRobot and collaborators at Harvard and Yale are working on versatile robot "hands" that can bear significant weight while also producing subtler gestures.
The latest three finger hand can open wide to pick up a basketball and can hoist a 50 pound weight, but is also able to use tweezers. Sometimes the robot hand works with two fingers and sometimes it uses all three depending on how it is grasping and stabilizing the objects it is interacting with. The researchers say function is more important than making the robot hands look human, which is probably for the best so they don't eventually show us up. [IEEE Spectrum]