Clearly with Poppy there is some serious down-scaling and simplification required to adapt any of these hand projects but simply having Poppy be able to grasp, say, a handle of a bucket or basket and carry it or perhaps push a button would be a huge advance.
I’m working on a miniature humanoid robotic hand for robots like Poppy.
It will be flexible and robust and I’m aiming to release it in around a month. There will probably be a 1DOF version that moves all fingers at once and a 5DOF version with individual finger movement. I would love some feedback to help make this exactly what you would want! There’s a short survey here. You can keep up to date on developments on twitter through @openbionics!
for very small scale hand like the one for poppy you should consider nitinol wire.
5 very simple spring and 5 short wires in the palm of the hand would allow you to move every finger alone. for sure, nitinol will not allow to be strong enough to grab objects, but it could be a start.
check this for nitinol. http://www.dynalloy.com/pdfs/TCF1140.pdf