Mystery Science is wonderful at given lots of easy to understand explanations without being too complicated. This activity is in depth and covers a multitude of mechanisms that help our bodies (and robot bodies like ours) to move. Caution to those who are unsettled by images of raw dead flesh as real animal flesh is used to exemplify how tendons work on muscles in our own bodies at one point in the video footage. I would have liked this source to start using real scientific phrasing to describe parts earlier, but they do eventually explain that the "strings" are actually tendons. This activity requires some printing, but if you or your student is up for it, you can create your own template. You can even make each finger anatomically correcting by measuring your own hand. If you want your robot hand to be able to do more, include a thumb.