Most robotic projects require a fair number of supplies. This one does not-all you need are rubber bands, straws, and a few other materials you will probably have at home. Admittedly the hand you build will not be "robotic" in the true sense of the word, but it does move in a robotic fashion-and it is very cool.

• Rubber bands*
• Straws*
• Cardboard
• Tape
• Scissors
• String
• Ruler

* Narrow straws and rubber bands work best.

1. Cut a piece of cardboard about 10 cm x 10 cm. This is the "palm" of the hand.
2. Cut three pieces of cardboard about 2 cm x 9 cm. These are the "fingers".
3. Cut one finger into three equal pieces.



4. Place the three finger pieces back together and put a piece of tape over the two finger joints.
5. Label the side with the tape "Inside".



6. Cut a piece of elastic about 5 cm long.
7. Turn the finger over (so the inside is face down) and place the elastic across middle of the first joint.
8. Tape the elastic on either side of the joint, leaving the ends of the elastic untaped. (Note: for this step, you may need to cut the tape to make it a bit thinner.)



9. Bend the ends of the elastic as shown and tape firmly. This will help prevent the elastic from slipping.



10. Repeat Steps 7 through 9 for the second joint.
11. Tape the finger (inside up) onto the palm.



12. Turn the hand over and fasten the last finger joint to the palm using the method described in Steps 7 through 9.



13. Cut a piece of string about 35 cm long and tape one end firmly over the end of the finger.
14. Cut four pieces of straw each about 2 cm long.
15. Thread the pieces of straw onto the string.



16. Tape three of the straws in the middle of each of the finger sections.
17. Tape the last straw to the palm as shown.



18. Repeat Steps 3 through 17 for the last two fingers.
19. Operate the hand by pulling the strings. You should be able to pick up empty soda cans and other light objects with your hand.

• If you are having trouble, make sure the rubber bands are taped tightly. If there is slippage, the hand will not work properly.
• What can you pick up with your hand?
• Try making a hand with more fingers or a thumb.