How to make a robot arm for animatronics.

To create a robot arm, you use a piece of corrugated plastic tubing, a CD case, twine, glue and duct tape. The manipulator itself is strong enough to hold, for example, a bottle or a cell phone.

First, make a robot hand template on a piece of paper using your own hand. Mark the hinges for each "finger".

Make “fingers” from the plastic tube that electricians use to run wires. The tube is easily cut with a regular stationery knife. Cut the tube to a length equal to the distance from the end of your finger to your wrist. Do this for all the “fingers” of the robotic hand. On the resulting tubes, mark the hinges with a marker and then make V-shaped cuts for each bend.

Insert and secure nylon twine into each tube finger. Leave the ends long enough (you can always trim them later).

Use an old CD case to get a piece of plastic. Using a cut out piece of plastic, connect the “fingers”: glue the “fingers” just below the knuckle joints.

Make sure you place the "fingers" in the correct order.

Now you can remove the electrical tape securing the string and make several turns of electrical tape to connect the “fingers” more tightly.

Glue the thumb as shown in the photo and secure it with electrical tape for strength.

Using the leftovers from your CD case, make a wrist.

It is better to strengthen the hand of the resulting robot arm by inserting it into a more rigid tube.

You can glue foam rubber to the “palm” and the ends of the “fingers”.

The robot arm can be used in a wide variety of animatronics projects. To control the hand, you can use servomotors by connecting the ends of the string to a “rocking chair” attached to their axis. Two servos are enough to make the robot's hand come to life. One servomotor is connected to the big “finger”, and the other to the rest. To make your hand look more impressive in animatronic projects, you can put a soft, thin glove on it.