Intro: Animatronic Tentacle
Halloween is just around the corner, and there has never been a better time to build yourself a tentacle arm! This project will teach you how to do just that, and since it uses animatronics, you can even control the movement of the tentacle!
Here is a video if it in action!
Step 1: Gather Materials
For this project you will need:
Two Large Zipties
String of some sort
3 Rubber Bands (2 of large and 1 of medium "stretchy-ness")
Electrical or Duct tape
Step 2: Building the Skeleton
For the first part of the assembly, you must build the skeleton of the tentacle. Lay out the two large zip-ties so they are parallel to one anther and a little less than two inches apart. Zip-ties tend to have an direction they want to "naturally" bend, so make sure that they are laid out so they both "naturally bend" the same way.Then cut the Popsicle sticks in half (wire cutters tend to work better then just scissors) and glue them between the zip-ties. Do this on both sides so as to ensure maximum durability. Then glue four half-Popsicle sticks down the center of the skeleton to act as a sort of spine. Place the spine sticks on the opposite side of the zip-ties "natural bend". Finally, loop the rubber bands over the spine sticks as shown in the last picture. Decide at this point which end is going to be the tip of your tentacle, and loop the two stronger rubber bands near the base, and the weaker one near the tip.
Step 3: Making It Moveable
Once the skeleton is constructed, you can add the animatronic element! Do this by cutting off 1 inch section of the thin coffee straws, then gluing them on the inside of the tentacle (opposite side of the "spine"). Then thread your string through the straws, tying and then gluing it in place at the top and then leaving some loose at the bottom.Lastly, tape the straws to the spine sticks so they will stay in place!
Step 4: Aesthetics
To make it look more tentacle-esque, cut strips of colored felt (I used orange but I figure green or even blue would also look good!) and hot glue them between the parallel Popsicle sticks. Then cut the ping pong balls in half. Hot glue pipe cleaner around the rim of the halved ping pong balls, then hot glue the balls onto the inside of the tentacle!
For the end of the tentacle, I simply broke a Popsicle stick in half then used it to create a triangle or "pointy" end. I then covered it in the felt.
Step 5: Controlling the Tentacle
To make the tentacle move, just hold it by the bottom and pull the string. This will cause the tentacle to contract inward, but against the rubber bands for a creepy, cephalopod effect!
For my design I built a "base" (basically just a square) with Popsicle sticks at the bottom so that I had somewhere to grasp it when pulling the string.
I like to control it by cutting a slit in the top of the cup and wedging the base in. I then wrap the string around two fingers (or even better tying it to a small zip-tie to serve as a handle) and then stick my fist in the cup. Then I pull the string with my fingers and move the tentacle around with my arm to use my tentacle arm!