It’s a robot! It’s a hand! It’s something you can make yourself!
Ilyssia is our expert Robot Hand engineer. Here is her quick description of the process.
First, I traced the shape of my hand onto the cardboard with all fingers spread apart. Don’t forget to add some space at the bottom for your wrist! I exaggerated the shape of my fingers (I made my fingers much bigger than they are!). My “super sized” fingers gave me room for the materials that would go on top of them.
Second, I cut out the shape I just drew on the cardboard.
Third, I have to make the fingers bend. So, I drew 2 lines on the thumb. I drew one line in the middle of my thumb cut out and one line at the bottom of the thumb cut out. These lines show where the joints will be. The finger joints are very similar, but there are three joints so each finger needs three lines.
Fourth, fold each line down on every finger and the thumb. Fold them back so the entire hand is open. (But now the fingers are more flexible!)
Straws & Strings – The tendons of the robotic hand
Fifth, take a straw and cut a piece for each section of the fingers and thumbs. They will have different lengths, but they are pretty short. My shortest straw was 0.5 inches (pinky finger!), but some straws were up to 2 inches long. The length of the straw depends on the distance between your folds.
Sixth, tape these straws to their proper section.
Seventh, cut more straws for the palm of the robotic hand. Tape these pieces in the palm area, not too far from the finger it will control. Point the other end of the straw toward the center of the wrist.
Eighth, cut one last piece of straw about 2 inches long. Tape it on the wrist so half of the straw sticks off the cutout.
Ninth, gather 5 pieces of string. Slide the string through all fingers, but leave a little extra at the top. Then, tape this extra piece on the back of each finger.
Tenth, push the ends of the string in the palm through the last straw piece on the wrist.
Finally, cut out about 2-3 inches of cardboard to hold your hand with (HA a pun).
Experiment with where you want to put this last piece of cardboard. You may like it in front of your hand (on the same side as the palm). Or, you may like it more on the other side of the hand where it will provide more support.
Now, when you pulling all the strings you can watch your robotic hand move!
Materials
If you bought one of our kits, you are in luck! You have a firm, thin piece of cardboard that we think is best. We also provided a much sturdier cardboard as the packaging. Finally, you will see that there is cardstock as well. See below for Ilyssia’s expert analysis of these materials; we suggest doing an initial test with the cardstock and then use the thin cardboard for your best design. If you want to make a sturdier hand or need more materials, take our box apart!
If you are finding additional supplies, we suggest cereal boxes and other boxes of that thickness. They provide the right strength without being too hard to manipulate like a shipping box.
Thoughts on Shipping Box Cardboard
Starting with this type of cardboard made it even more difficult. I cut the fingers too close together and the friction between the fingers made it hard for them to move. And, it was very hard to cut out in the shape I wanted.
Thoughts on Shipping Box Cardboard
The regular brown paper was easy to cut out. But, the brown paper is too weak to pick anything up so it isn’t useful either.
Thoughts on using Paper
card stock paper which was the easiest material. Making the fingers large and spreading them apart really helped in making the robot. I switched to burlap instead of the elastic string so moving the fingers was easy. Also, I put the card board piece on the back of the wrist rather than the front to hold the robot a different way.